Merging upstream version 1.66.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

64 files changed, 30101 insertions, 0 deletions

diff --git a/vendor/clap-3.2.20/src/_cookbook/cargo_example.rs b/vendor/clap-3.2.20/src/_cookbook/cargo_example.rs
new file mode 100644
index 000000000..ec5d582db
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/cargo_example.rs
@@ -0,0 +1,7 @@
+//! # Example: cargo subcommand (Builder API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/cargo-example.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/cargo-example.md")]
diff --git a/vendor/clap-3.2.20/src/_cookbook/cargo_example_derive b/vendor/clap-3.2.20/src/_cookbook/cargo_example_derive
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/cargo_example_derive
diff --git a/vendor/clap-3.2.20/src/_cookbook/cargo_example_derive.rs b/vendor/clap-3.2.20/src/_cookbook/cargo_example_derive.rs
new file mode 100644
index 000000000..d49f956f9
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/cargo_example_derive.rs
@@ -0,0 +1,7 @@
+//! # Example: cargo subcommand (Derive API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/cargo-example-derive.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/cargo-example-derive.md")]
diff --git a/vendor/clap-3.2.20/src/_cookbook/escaped_positional.rs b/vendor/clap-3.2.20/src/_cookbook/escaped_positional.rs
new file mode 100644
index 000000000..99a3f83f3
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/escaped_positional.rs
@@ -0,0 +1,7 @@
+//! # Example (Builder API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/escaped-positional.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/escaped-positional.md")]
diff --git a/vendor/clap-3.2.20/src/_cookbook/escaped_positional_derive.rs b/vendor/clap-3.2.20/src/_cookbook/escaped_positional_derive.rs
new file mode 100644
index 000000000..e6f99ad17
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/escaped_positional_derive.rs
@@ -0,0 +1,7 @@
+//! # Example (Derive API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/escaped-positional-derive.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/escaped-positional-derive.md")]
diff --git a/vendor/clap-3.2.20/src/_cookbook/git.rs b/vendor/clap-3.2.20/src/_cookbook/git.rs
new file mode 100644
index 000000000..03a926ca8
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/git.rs
@@ -0,0 +1,7 @@
+//! # Example: git-like CLI (Builder API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/git.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/git.md")]
diff --git a/vendor/clap-3.2.20/src/_cookbook/git_derive.rs b/vendor/clap-3.2.20/src/_cookbook/git_derive.rs
new file mode 100644
index 000000000..d3119736d
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/git_derive.rs
@@ -0,0 +1,7 @@
+//! # Example: git-like CLI (Derive API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/git-derive.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/git-derive.md")]
diff --git a/vendor/clap-3.2.20/src/_cookbook/mod.rs b/vendor/clap-3.2.20/src/_cookbook/mod.rs
new file mode 100644
index 000000000..1a78ed11b
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/mod.rs
@@ -0,0 +1,55 @@
+// Contributing
+//
+// New examples:
+// - Building: They must be added to `Cargo.toml` with the appropriate `required-features`.
+// - Testing: Ensure there is a markdown file with [trycmd](https://docs.rs/trycmd) syntax
+// - Link the `.md` file from here
+
+//! # Documentation: Cookbook
+//!
+//! Typed arguments: [derive][typed_derive]
+//! - Topics:
+//!   - Custom `parse()`
+//!
+//! Custom cargo command: [builder][cargo_example], [derive][cargo_example_derive]
+//! - Topics:
+//!   - Subcommands
+//!   - Cargo plugins
+//!
+//! git-like interface: [builder][git], [derive][git_derive]
+//! - Topics:
+//!   - Subcommands
+//!   - External subcommands
+//!   - Optional subcommands
+//!   - Default subcommands
+//!
+//! pacman-like interface: [builder][pacman]
+//! - Topics:
+//!   - Flag subcommands
+//!   - Conflicting arguments
+//!
+//! Escaped positionals with `--`: [builder][escaped_positional], [derive][escaped_positional_derive]
+//!
+//! Multi-call
+//! - busybox: [builder][multicall_busybox]
+//!   - Topics:
+//!     - Subcommands
+//! - hostname: [builder][multicall_hostname]
+//!   - Topics:
+//!     - Subcommands
+//!
+//! repl: [builder][repl]
+//! - Topics:
+//!   - Read-Eval-Print Loops / Custom command lines
+
+pub mod cargo_example;
+pub mod cargo_example_derive;
+pub mod escaped_positional;
+pub mod escaped_positional_derive;
+pub mod git;
+pub mod git_derive;
+pub mod multicall_busybox;
+pub mod multicall_hostname;
+pub mod pacman;
+pub mod repl;
+pub mod typed_derive;
diff --git a/vendor/clap-3.2.20/src/_cookbook/multicall_busybox.rs b/vendor/clap-3.2.20/src/_cookbook/multicall_busybox.rs
new file mode 100644
index 000000000..e3384d682
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/multicall_busybox.rs
@@ -0,0 +1,7 @@
+//! # Example: busybox-like CLI (Builder API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/multicall-busybox.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/multicall-busybox.md")]
diff --git a/vendor/clap-3.2.20/src/_cookbook/multicall_hostname.rs b/vendor/clap-3.2.20/src/_cookbook/multicall_hostname.rs
new file mode 100644
index 000000000..9777654dc
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/multicall_hostname.rs
@@ -0,0 +1,7 @@
+//! # Example: hostname-like CLI (Builder API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/multicall-hostname.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/multicall-hostname.md")]
diff --git a/vendor/clap-3.2.20/src/_cookbook/pacman.rs b/vendor/clap-3.2.20/src/_cookbook/pacman.rs
new file mode 100644
index 000000000..880c58158
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/pacman.rs
@@ -0,0 +1,7 @@
+//! # Example: pacman-like CLI (Builder API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/pacman.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/pacman.md")]
diff --git a/vendor/clap-3.2.20/src/_cookbook/repl.rs b/vendor/clap-3.2.20/src/_cookbook/repl.rs
new file mode 100644
index 000000000..549ec8259
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/repl.rs
@@ -0,0 +1,5 @@
+//! # Example: Command REPL (Builder API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/repl.rs")]
+//! ```
diff --git a/vendor/clap-3.2.20/src/_cookbook/typed_derive.rs b/vendor/clap-3.2.20/src/_cookbook/typed_derive.rs
new file mode 100644
index 000000000..a5fd15ff8
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_cookbook/typed_derive.rs
@@ -0,0 +1,7 @@
+//! # Example: Custom Types (Derive API)
+//!
+//! ```rust
+#![doc = include_str!("../../examples/typed-derive.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/typed-derive.md")]
diff --git a/vendor/clap-3.2.20/src/_derive/_tutorial.rs b/vendor/clap-3.2.20/src/_derive/_tutorial.rs
new file mode 100644
index 000000000..abd57cef8
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_derive/_tutorial.rs
@@ -0,0 +1,205 @@
+// Contributing
+//
+// New example code:
+// - Please update the corresponding section in the derive tutorial
+// - Building: They must be added to `Cargo.toml` with the appropriate `required-features`.
+// - Testing: Ensure there is a markdown file with [trycmd](https://docs.rs/trycmd) syntax
+//
+// See also the general CONTRIBUTING
+
+//! # Documentation: Derive Tutorial
+//!
+//! 1. [Quick Start](#quick-start)
+//! 2. [Configuring the Parser](#configuring-the-parser)
+//! 3. [Adding Arguments](#adding-arguments)
+//!     1. [Positionals](#positionals)
+//!     2. [Options](#options)
+//!     3. [Flags](#flags)
+//!     4. [Subcommands](#subcommands)
+//!     5. [Defaults](#defaults)
+//! 4. Validation
+//!     1. [Enumerated values](#enumerated-values)
+//!     2. [Validated values](#validated-values)
+//!     3. [Argument Relations](#argument-relations)
+//!     4. [Custom Validation](#custom-validation)
+//! 5. [Testing](#testing)
+//!
+//! See also
+//! - [FAQ: When should I use the builder vs derive APIs?][crate::_faq#when-should-i-use-the-builder-vs-derive-apis]
+//! - The [cookbook][crate::_cookbook] for more application-focused examples
+//!
+//! ## Quick Start
+//!
+//! You can create an application declaratively with a `struct` and some
+//! attributes.  **This requires enabling the [`derive` feature flag][crate::_features].**
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/01_quick.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/tutorial_derive/01_quick.md")]
+//!
+//! ## Configuring the Parser
+//!
+//! You use derive [`Parser`][crate::Parser] to start building a parser.
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/02_apps.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/tutorial_derive/02_apps.md")]
+//!
+//! You can use `#[clap(author, version, about)]` attribute defaults to fill these fields in from your `Cargo.toml` file.
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/02_crate.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/02_crate.md")]
+//!
+//! You can use attributes to change the application level behavior of clap.  Any [`Command`][crate::Command]] builder function can be used as an attribute.
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/02_app_settings.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/02_app_settings.md")]
+//!
+//! ## Adding Arguments
+//!
+//! ### Positionals
+//!
+//! You can have users specify values by their position on the command-line:
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/03_03_positional.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/03_03_positional.md")]
+//!
+//! ### Options
+//!
+//! You can name your arguments with a flag:
+//! - Order doesn't matter
+//! - They can be optional
+//! - Intent is clearer
+//!
+//! The `#[clap(short = 'n')]` and `#[clap(long = "name")]` attributes that define
+//! the flags are [`Arg`][crate::Args] methods that are derived from the field name when no value
+//! is specified (`#[clap(short)]` and `#[clap(long)]`).
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/03_02_option.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/03_02_option.md")]
+//!
+//! ### Flags
+//!
+//! Flags can also be switches that can be on/off.  This is enabled via the
+//! `#[clap(action = ArgAction::SetTrue)]` attribute though this is implied when the field is a
+//! `bool`.
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/03_01_flag_bool.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/03_01_flag_bool.md")]
+//!
+//! Or counted with `#[clap(action = clap::ArgAction::Count)]`:
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/03_01_flag_count.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/03_01_flag_count.md")]
+//!
+//! ### Subcommands
+//!
+//! Subcommands are derived with `#[derive(Subcommand)]` and be added via `#[clap(subcommand)]` attribute. Each
+//! instance of a [Subcommand][crate::Subcommand] can have its own version, author(s), Args, and even its own
+//! subcommands.
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/03_04_subcommands.rs")]
+//! ```
+//! We used a struct-variant to define the `add` subcommand.
+//! Alternatively, you can use a struct for your subcommand's arguments:
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/03_04_subcommands_alt.rs")]
+//! ```
+//!
+#![doc = include_str!("../../examples/tutorial_derive/03_04_subcommands.md")]
+//!
+//! ### Defaults
+//!
+//! We've previously showed that arguments can be [`required`][crate::Arg::required] or optional.
+//! When optional, you work with a `Option` and can `unwrap_or`.  Alternatively, you can
+//! set `#[clap(default_value_t)]`.
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/03_05_default_values.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/03_05_default_values.md")]
+//!
+//! ## Validation
+//!
+//! ### Enumerated values
+//!
+//! If you have arguments of specific values you want to test for, you can derive
+//! [`ValueEnum`][crate::ValueEnum].
+//!
+//! This allows you specify the valid values for that argument. If the user does not use one of
+//! those specific values, they will receive a graceful exit with error message informing them
+//! of the mistake, and what the possible valid values are
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/04_01_enum.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/04_01_enum.md")]
+//!
+//! ### Validated values
+//!
+//! More generally, you can validate and parse into any data type.
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/04_02_parse.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/04_02_parse.md")]
+//!
+//! A custom parser can be used to improve the error messages or provide additional validation:
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/04_02_validate.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/04_02_validate.md")]
+//!
+//! ### Argument Relations
+//!
+//! You can declare dependencies or conflicts between [`Arg`][crate::Arg]s or even
+//! [`ArgGroup`][crate::ArgGroup]s.
+//!
+//! [`ArgGroup`][crate::ArgGroup]s  make it easier to declare relations instead of having to list
+//! each individually, or when you want a rule to apply "any but not all" arguments.
+//!
+//! Perhaps the most common use of [`ArgGroup`][crate::ArgGroup]s is to require one and *only* one
+//! argument to be present out of a given set. Imagine that you had multiple arguments, and you
+//! want one of them to be required, but making all of them required isn't feasible because perhaps
+//! they conflict with each other.
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/04_03_relations.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/04_03_relations.md")]
+//!
+//! ### Custom Validation
+//!
+//! As a last resort, you can create custom errors with the basics of clap's formatting.
+//!
+//! ```rust
+#![doc = include_str!("../../examples/tutorial_derive/04_04_custom.rs")]
+//! ```
+#![doc = include_str!("../../examples/tutorial_derive/04_04_custom.md")]
+//!
+//! ## Testing
+//!
+//! clap reports most development errors as `debug_assert!`s.  Rather than checking every
+//! subcommand, you should have a test that calls
+//! [`Command::debug_assert`][crate::App::debug_assert]:
+//! ```rust,no_run
+#![doc = include_str!("../../examples/tutorial_derive/05_01_assert.rs")]
+//! ```
diff --git a/vendor/clap-3.2.20/src/_derive/mod.rs b/vendor/clap-3.2.20/src/_derive/mod.rs
new file mode 100644
index 000000000..fc9f35db5
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_derive/mod.rs
@@ -0,0 +1,510 @@
+//! # Documentation: Derive Reference
+//!
+//! 1. [Overview](#overview)
+//! 2. [Attributes](#attributes)
+//!     1. [Terminology](#terminology)
+//!     2. [Command Attributes](#command-attributes)
+//!     3. [Arg Attributes](#arg-attributes)
+//!     4. [ValueEnum Attributes](#valueenum-attributes)
+//!     5. [Possible Value Attributes](#possible-value-attributes)
+//! 3. [Arg Types](#arg-types)
+//! 4. [Doc Comments](#doc-comments)
+//! 5. [Mixing Builder and Derive APIs](#mixing-builder-and-derive-apis)
+//! 6. [Tips](#tips)
+//!
+//! ## Overview
+//!
+//! To derive `clap` types, you need to enable the [`derive` feature flag][crate::_features].
+//!
+//! Example:
+//! ```rust
+#![doc = include_str!("../../examples/demo.rs")]
+//! ```
+//!
+//! Let's start by breaking down the anatomy of the derive attributes:
+//! ```rust
+//! use clap::{Parser, Args, Subcommand, ValueEnum};
+//!
+//! /// Doc comment
+//! #[derive(Parser)]
+//! #[clap(APP ATTRIBUTE)]
+//! struct Cli {
+//!     /// Doc comment
+//!     #[clap(ARG ATTRIBUTE)]
+//!     field: UserType,
+//!
+//!     #[clap(value_enum, ARG ATTRIBUTE...)]
+//!     field: EnumValues,
+//!
+//!     #[clap(flatten)]
+//!     delegate: Struct,
+//!
+//!     #[clap(subcommand)]
+//!     command: Command,
+//! }
+//!
+//! /// Doc comment
+//! #[derive(Args)]
+//! #[clap(PARENT APP ATTRIBUTE)]
+//! struct Struct {
+//!     /// Doc comment
+//!     #[clap(ARG ATTRIBUTE)]
+//!     field: UserType,
+//! }
+//!
+//! /// Doc comment
+//! #[derive(Subcommand)]
+//! #[clap(PARENT APP ATTRIBUTE)]
+//! enum Command {
+//!     /// Doc comment
+//!     #[clap(APP ATTRIBUTE)]
+//!     Variant1(Struct),
+//!
+//!     /// Doc comment
+//!     #[clap(APP ATTRIBUTE)]
+//!     Variant2 {
+//!         /// Doc comment
+//!         #[clap(ARG ATTRIBUTE)]
+//!         field: UserType,
+//!     }
+//! }
+//!
+//! /// Doc comment
+//! #[derive(ValueEnum)]
+//! #[clap(VALUE ENUM ATTRIBUTE)]
+//! enum EnumValues {
+//!     /// Doc comment
+//!     #[clap(POSSIBLE VALUE ATTRIBUTE)]
+//!     Variant1,
+//! }
+//!
+//! fn main() {
+//!     let cli = Cli::parse();
+//! }
+//! ```
+//!
+//! Traits:
+//! - [`Parser`][crate::Parser] parses arguments into a `struct` (arguments) or `enum` (subcommands).
+//!   - [`Args`][crate::Args] allows defining a set of re-usable arguments that get merged into their parent container.
+//!   - [`Subcommand`][crate::Subcommand] defines available subcommands.
+//!   - Subcommand arguments can be defined in a struct-variant or automatically flattened with a tuple-variant.
+//! - [`ValueEnum`][crate::ValueEnum] allows parsing a value directly into an `enum`, erroring on unsupported values.
+//!   - The derive doesn't work on enums that contain non-unit variants, unless they are skipped
+//!
+//! *See also the [derive tutorial][crate::_derive::_tutorial] and [cookbook][crate::_cookbook]*
+//!
+//! ## Attributes
+//!
+//! ### Terminology
+//!
+//! **Raw attributes** are forwarded directly to the underlying [`clap` builder][crate::builder].  Any
+//! [`Command`][crate::Command], [`Arg`][crate::Arg], or [`PossibleValue`][crate::PossibleValue] method can be used as an attribute.
+//!
+//! Raw attributes come in two different syntaxes:
+//! ```rust,ignore
+//! #[clap(
+//!     global = true, // name = arg form, neat for one-arg methods
+//!     required_if_eq("out", "file") // name(arg1, arg2, ...) form.
+//! )]
+//! ```
+//!
+//! - `method = arg` can only be used for methods which take only one argument.
+//! - `method(arg1, arg2)` can be used with any method.
+//!
+//! As long as `method_name` is not one of the magical methods it will be
+//! translated into a mere method call.
+//!
+//! **Magic attributes** have post-processing done to them, whether that is
+//! - Providing of defaults
+//! - Special behavior is triggered off of it
+//!
+//! Magic attributes are more constrained in the syntax they support, usually just
+//! `<attr> = <value>` though some use `<attr>(<value>)` instead.  See the specific
+//! magic attributes documentation for details.  This allows users to access the
+//! raw behavior of an attribute via `<attr>(<value>)` syntax.
+//!
+//! **NOTE:** Some attributes are inferred from [Arg Types](#arg-types) and [Doc
+//! Comments](#doc-comments).  Explicit attributes take precedence over inferred
+//! attributes.
+//!
+//! ### Command Attributes
+//!
+//! These correspond to a [`Command`][crate::Command] which is used for both top-level parsers and
+//! when defining subcommands.
+//!
+//! **Raw attributes:**  Any [`Command` method][crate::Command] can also be used as an attribute,
+//! see [Terminology](#terminology) for syntax.
+//! - e.g. `#[clap(arg_required_else_help(true))]` would translate to `cmd.arg_required_else_help(true)`
+//!
+//! **Magic attributes:**
+//! - `name  = <expr>`: [`Command::name`][crate::App::name]
+//!   - When not present: [crate `name`](https://doc.rust-lang.org/cargo/reference/manifest.html#the-name-field) (if on [`Parser`][crate::Parser] container), variant name (if on [`Subcommand`][crate::Subcommand] variant)
+//! - `version [= <expr>]`: [`Command::version`][crate::App::version]
+//!   - When not present: no version set
+//!   - Without `<expr>`: defaults to [crate `version`](https://doc.rust-lang.org/cargo/reference/manifest.html#the-version-field)
+//! - `author [= <expr>]`: [`Command::author`][crate::App::author]
+//!   - When not present: no author set
+//!   - Without `<expr>`: defaults to [crate `authors`](https://doc.rust-lang.org/cargo/reference/manifest.html#the-authors-field)
+//! - `about [= <expr>]`: [`Command::about`][crate::App::about]
+//!   - When not present: [Doc comment summary](#doc-comments)
+//!   - Without `<expr>`: [crate `description`](https://doc.rust-lang.org/cargo/reference/manifest.html#the-description-field) ([`Parser`][crate::Parser] container)
+//!     - **TIP:** When a doc comment is also present, you most likely want to add
+//!       `#[clap(long_about = None)]` to clear the doc comment so only [`about`][crate::App::about]
+//!       gets shown with both `-h` and `--help`.
+//! - `long_about = <expr>`: [`Command::long_about`][crate::App::long_about]
+//!   - When not present: [Doc comment](#doc-comments) if there is a blank line, else nothing
+//! - `verbatim_doc_comment`: Minimizes pre-processing when converting doc comments to [`about`][crate::App::about] / [`long_about`][crate::App::long_about]
+//! - `next_display_order`: [`Command::next_display_order`][crate::App::next_display_order]
+//! - `next_help_heading`: [`Command::next_help_heading`][crate::App::next_help_heading]
+//!   - When `flatten`ing [`Args`][crate::Args], this is scoped to just the args in this struct and any struct `flatten`ed into it
+//! - `rename_all = <string_literal>`: Override default field / variant name case conversion for [`Command::name`][crate::Command::name] / [`Arg::id`][crate::Arg::id]
+//!   - When not present: `"kebab-case"`
+//!   - Available values: `"camelCase"`, `"kebab-case"`, `"PascalCase"`, `"SCREAMING_SNAKE_CASE"`, `"snake_case"`, `"lower"`, `"UPPER"`, `"verbatim"`
+//! - `rename_all_env = <string_literal>`: Override default field name case conversion for env variables for  [`Arg::env`][crate::Arg::env]
+//!   - When not present: `"SCREAMING_SNAKE_CASE"`
+//!   - Available values: `"camelCase"`, `"kebab-case"`, `"PascalCase"`, `"SCREAMING_SNAKE_CASE"`, `"snake_case"`, `"lower"`, `"UPPER"`, `"verbatim"`
+//!
+//! And for [`Subcommand`][crate::Subcommand] variants:
+//! - `skip`: Ignore this variant
+//! - `flatten`: Delegates to the variant for more subcommands (must implement
+//!   [`Subcommand`][crate::Subcommand])
+//! - `subcommand`: Nest subcommands under the current set of subcommands (must implement
+//!   [`Subcommand`][crate::Subcommand])
+//! - `external_subcommand`: [`Command::allow_external_subcommand(true)`][crate::App::allow_external_subcommands]
+//!   - Variant must be either `Variant(Vec<String>)` or `Variant(Vec<OsString>)`
+//!
+//! ### Arg Attributes
+//!
+//! These correspond to a [`Arg`][crate::Arg].
+//!
+//! **Raw attributes:**  Any [`Arg` method][crate::Arg] can also be used as an attribute, see [Terminology](#terminology) for syntax.
+//! - e.g. `#[clap(max_values(3))]` would translate to `arg.max_values(3)`
+//!
+//! **Magic attributes**:
+//! - `id = <expr>`: [`Arg::id`][crate::Arg::id]
+//!   - When not present: case-converted field name is used
+//! - `name = <expr>`: [`Arg::id`][crate::Arg::id]
+//!   - **Deprecated:** use `id`
+//! - `value_parser [= <expr>]`: [`Arg::value_parser`][crate::Arg::value_parser]
+//!   - When not present: will auto-select an implementation based on the field type using
+//!     [`value_parser!][crate::value_parser!]
+//!   - When present but defaulted: opt-in to clap v4 semantics
+//!     - Env parsing is now dependent on inferred parser
+//!     - `PathBuf` will implicitly skip UTF-8 validation (before it required specifying
+//!       `try_from_os_str`)
+//!   - When present, implies `#[clap(action)]`
+//!   - To register a custom type's [`ValueParser`][crate::builder::ValueParser], implement [`ValueParserFactory`][crate::builder::ValueParserFactory]
+//! - `action [= <expr>]`: [`Arg::action`][crate::Arg::action]
+//!   - When not present: will auto-select an action based on the field type
+//!   - When present but defaulted: opt-in to clap v4 semantics
+//!   - When present, implies `#[clap(value_parser)]`
+//!     - `args_override_self` is forced on for single flags
+//! - `help = <expr>`: [`Arg::help`][crate::Arg::help]
+//!   - When not present: [Doc comment summary](#doc-comments)
+//! - `long_help = <expr>`: [`Arg::long_help`][crate::Arg::long_help]
+//!   - When not present: [Doc comment](#doc-comments) if there is a blank line, else nothing
+//! - `verbatim_doc_comment`: Minimizes pre-processing when converting doc comments to [`help`][crate::Arg::help] / [`long_help`][crate::Arg::long_help]
+//! - `short [= <char>]`: [`Arg::short`][crate::Arg::short]
+//!   - When not present: no short set
+//!   - Without `<char>`: defaults to first character in the case-converted field name
+//! - `long [= <str>]`: [`Arg::long`][crate::Arg::long]
+//!   - When not present: no long set
+//!   - Without `<str>`: defaults to the case-converted field name
+//! - `env [= <str>]`: [`Arg::env`][crate::Arg::env] (needs [`env` feature][crate::_features] enabled)
+//!   - When not present: no env set
+//!   - Without `<str>`: defaults to the case-converted field name
+//! - `flatten`: Delegates to the field for more arguments (must implement [`Args`][crate::Args])
+//!   - Only [`next_help_heading`][crate::Command::next_help_heading] can be used with `flatten`.  See
+//!     [clap-rs/clap#3269](https://github.com/clap-rs/clap/issues/3269) for why
+//!     arg attributes are not generally supported.
+//!   - **Tip:** Though we do apply a flattened [`Args`][crate::Args]'s Parent Command Attributes, this
+//!     makes reuse harder. Generally prefer putting the cmd attributes on the
+//!     [`Parser`][crate::Parser] or on the flattened field.
+//! - `subcommand`: Delegates definition of subcommands to the field (must implement
+//!   [`Subcommand`][crate::Subcommand])
+//!   - When `Option<T>`, the subcommand becomes optional
+//! - `from_global`: Read a [`Arg::global`][crate::Arg::global] argument (raw attribute), regardless of what subcommand you are in
+//! - `parse(<kind> [= <function>])`: [`Arg::validator`][crate::Arg::validator] and [`ArgMatches::values_of_t`][crate::ArgMatches::values_of_t]
+//!   - **Deprecated:**
+//!     - Use `value_parser(...)` for `from_str`, `try_from_str`, `from_os_str`, and `try_from_os_str`
+//!     - Use `action(ArgAction::Count` for `from_occurrences`
+//!     - Use `action(ArgAction::SetTrue` for `from_flag`
+//!   - Default: `try_from_str`
+//!   - Warning: for `Path` / `OsString`, be sure to use `try_from_os_str`
+//!   - See [Arg Types](#arg-types) for more details
+//! - `value_enum`: Parse the value using the [`ValueEnum`][crate::ValueEnum]
+//! - `skip [= <expr>]`: Ignore this field, filling in with `<expr>`
+//!   - Without `<expr>`: fills the field with `Default::default()`
+//! - `default_value = <str>`: [`Arg::default_value`][crate::Arg::default_value] and [`Arg::required(false)`][crate::Arg::required]
+//! - `default_value_t [= <expr>]`: [`Arg::default_value`][crate::Arg::default_value] and [`Arg::required(false)`][crate::Arg::required]
+//!   - Requires `std::fmt::Display` or `#[clap(value_enum)]`
+//!   - Without `<expr>`, relies on `Default::default()`
+//! - `default_values_t = <expr>`: [`Arg::default_values`][crate::Arg::default_values] and [`Arg::required(false)`][crate::Arg::required]
+//!   - Requires field arg to be of type `Vec<T>` and `T` to implement `std::fmt::Display` or `#[clap(value_enum)]`
+//!   - `<expr>` must implement `IntoIterator<T>`
+//! - `default_value_os_t [= <expr>]`: [`Arg::default_value_os`][crate::Arg::default_value_os] and [`Arg::required(false)`][crate::Arg::required]
+//!   - Requires `std::convert::Into<OsString>` or `#[clap(value_enum)]`
+//!   - Without `<expr>`, relies on `Default::default()`
+//! - `default_values_os_t = <expr>`: [`Arg::default_values_os`][crate::Arg::default_values_os] and [`Arg::required(false)`][crate::Arg::required]
+//!   - Requires field arg to be of type `Vec<T>` and `T` to implement `std::convert::Into<OsString>` or `#[clap(value_enum)]`
+//!   - `<expr>` must implement `IntoIterator<T>`
+//!
+//! ### ValueEnum Attributes
+//!
+//! - `rename_all = <string_literal>`: Override default field / variant name case conversion for [`PossibleValue::new`][crate::PossibleValue]
+//!   - When not present: `"kebab-case"`
+//!   - Available values: `"camelCase"`, `"kebab-case"`, `"PascalCase"`, `"SCREAMING_SNAKE_CASE"`, `"snake_case"`, `"lower"`, `"UPPER"`, `"verbatim"`
+//!
+//! ### Possible Value Attributes
+//!
+//! These correspond to a [`PossibleValue`][crate::PossibleValue].
+//!
+//! **Raw attributes:**  Any [`PossibleValue` method][crate::PossibleValue] can also be used as an attribute, see [Terminology](#terminology) for syntax.
+//! - e.g. `#[clap(alias("foo"))]` would translate to `pv.alias("foo")`
+//!
+//! **Magic attributes**:
+//! - `name = <expr>`: [`PossibleValue::new`][crate::PossibleValue::new]
+//!   - When not present: case-converted field name is used
+//! - `help = <expr>`: [`PossibleValue::help`][crate::PossibleValue::help]
+//!   - When not present: [Doc comment summary](#doc-comments)
+//!
+//! ## Arg Types
+//!
+//! `clap` assumes some intent based on the type used:
+//!
+//! | Type                | Effect                               | Implies                                                          |
+//! |---------------------|--------------------------------------|------------------------------------------------------------------|
+//! | `bool`              | flag                                 | `#[clap(parse(from_flag))]`                                     |
+//! | `Option<T>`         | optional argument                    | `.takes_value(true).required(false)`                             |
+//! | `Option<Option<T>>` | optional value for optional argument | `.takes_value(true).required(false).min_values(0).max_values(1)` |
+//! | `T`                 | required argument                    | `.takes_value(true).required(!has_default)`                      |
+//! | `Vec<T>`            | `0..` occurrences of argument        | `.takes_value(true).required(false).multiple_occurrences(true)`  |
+//! | `Option<Vec<T>>`    | `0..` occurrences of argument        | `.takes_value(true).required(false).multiple_occurrences(true)`  |
+//!
+//! Notes:
+//! - For custom type behavior, you can override the implied attributes/settings and/or set additional ones
+//!   - For example, see [custom-bool](./custom-bool.md)
+//! - `Option<Vec<T>>` will be `None` instead of `vec![]` if no arguments are provided.
+//!   - This gives the user some flexibility in designing their argument, like with `min_values(0)`
+//!
+//! You can then support your custom type with `#[clap(parse(<kind> [= <function>]))]`:
+//!
+//! | `<kind>`                 | Signature                             | Default `<function>`            |
+//! |--------------------------|---------------------------------------|---------------------------------|
+//! | `from_str`               | `fn(&str) -> T`                       | `::std::convert::From::from`    |
+//! | `try_from_str` (default) | `fn(&str) -> Result<T, E>`            | `::std::str::FromStr::from_str` |
+//! | `from_os_str`            | `fn(&OsStr) -> T`                     | `::std::convert::From::from`    |
+//! | `try_from_os_str`        | `fn(&OsStr) -> Result<T, E>`          | (no default function)           |
+//! | `from_occurrences`       | `fn(u64) -> T`                        | `value as T`                    |
+//! | `from_flag`              | `fn(bool) -> T`                       | `::std::convert::From::from`    |
+//!
+//! Notes:
+//! - `from_os_str`:
+//!   - Implies `arg.takes_value(true).allow_invalid_utf8(true)`
+//! - `try_from_os_str`:
+//!   - Implies `arg.takes_value(true).allow_invalid_utf8(true)`
+//! - `from_occurrences`:
+//!   - Implies `arg.takes_value(false).multiple_occurrences(true)`
+//!   - Reads from `clap::ArgMatches::occurrences_of` rather than a `get_one` function
+//!     - Note: operations on values, like `default_value`, are unlikely to do what you want
+//! - `from_flag`
+//!   - Implies `arg.takes_value(false)`
+//!   - Reads from `clap::ArgMatches::is_present` rather than a `get_one` function
+//!     - Note: operations on values, like `default_value`, are unlikely to do what you want
+//!
+//! **Warning:**
+//! - To support non-UTF8 paths, you should use `#[clap(value_parser)]` otherwise
+//!   `clap` will parse it as a `String` which will fail on some paths.
+//!
+//! ## Doc Comments
+//!
+//! In clap, help messages for the whole binary can be specified
+//! via [`Command::about`][crate::App::about] and [`Command::long_about`][crate::App::long_about] while help messages
+//! for individual arguments can be specified via [`Arg::help`][crate::Arg::help] and [`Arg::long_help`][crate::Arg::long_help].
+//!
+//! `long_*` variants are used when user calls the program with
+//! `--help` and "short" variants are used with `-h` flag.
+//!
+//! ```rust
+//! # use clap::Parser;
+//!
+//! #[derive(Parser)]
+//! #[clap(about = "I am a program and I work, just pass `-h`", long_about = None)]
+//! struct Foo {
+//!     #[clap(short, help = "Pass `-h` and you'll see me!")]
+//!     bar: String,
+//! }
+//! ```
+//!
+//! For convenience, doc comments can be used instead of raw methods
+//! (this example works exactly like the one above):
+//!
+//! ```rust
+//! # use clap::Parser;
+//!
+//! #[derive(Parser)]
+//! /// I am a program and I work, just pass `-h`
+//! struct Foo {
+//!     /// Pass `-h` and you'll see me!
+//!     bar: String,
+//! }
+//! ```
+//!
+//! **NOTE:** Attributes have priority over doc comments!
+//!
+//! **Top level doc comments always generate `Command::about/long_about` calls!**
+//! If you really want to use the `Command::about/long_about` methods (you likely don't),
+//! use the `about` / `long_about` attributes to override the calls generated from
+//! the doc comment.  To clear `long_about`, you can use
+//! `#[clap(long_about = None)]`.
+//!
+//! **TIP:** Set `#![deny(missing_docs)]` to catch missing `--help` documentation at compile time.
+//!
+//! ### Pre-processing
+//!
+//! ```rust
+//! # use clap::Parser;
+//! #[derive(Parser)]
+//! /// Hi there, I'm Robo!
+//! ///
+//! /// I like beeping, stumbling, eating your electricity,
+//! /// and making records of you singing in a shower.
+//! /// Pay up, or I'll upload it to youtube!
+//! struct Robo {
+//!     /// Call my brother SkyNet.
+//!     ///
+//!     /// I am artificial superintelligence. I won't rest
+//!     /// until I'll have destroyed humanity. Enjoy your
+//!     /// pathetic existence, you mere mortals.
+//!     #[clap(long, action)]
+//!     kill_all_humans: bool,
+//! }
+//! ```
+//!
+//! A doc comment consists of three parts:
+//! - Short summary
+//! - A blank line (whitespace only)
+//! - Detailed description, all the rest
+//!
+//! The summary corresponds with `Command::about` / `Arg::help`.  When a blank line is
+//! present, the whole doc comment will be passed to `Command::long_about` /
+//! `Arg::long_help`.  Or in other words, a doc may result in just a `Command::about` /
+//! `Arg::help` or `Command::about` / `Arg::help` and `Command::long_about` /
+//! `Arg::long_help`
+//!
+//! In addition, when `verbatim_doc_comment` is not present, `clap` applies some preprocessing, including:
+//!
+//! - Strip leading and trailing whitespace from every line, if present.
+//!
+//! - Strip leading and trailing blank lines, if present.
+//!
+//! - Interpret each group of non-empty lines as a word-wrapped paragraph.
+//!
+//!   We replace newlines within paragraphs with spaces to allow the output
+//!   to be re-wrapped to the terminal width.
+//!
+//! - Strip any excess blank lines so that there is exactly one per paragraph break.
+//!
+//! - If the first paragraph ends in exactly one period,
+//!   remove the trailing period (i.e. strip trailing periods but not trailing ellipses).
+//!
+//! Sometimes you don't want this preprocessing to apply, for example the comment contains
+//! some ASCII art or markdown tables, you would need to preserve LFs along with
+//! blank lines and the leading/trailing whitespace. When you pass use the
+//! `verbatim_doc_comment` magic attribute, you  preserve
+//! them.
+//!
+//! **Note:** Keep in mind that `verbatim_doc_comment` will *still*
+//! - Remove one leading space from each line, even if this attribute is present,
+//!   to allow for a space between `///` and the content.
+//! - Remove leading and trailing blank lines
+//!
+//! ## Mixing Builder and Derive APIs
+//!
+//! The builder and derive APIs do not live in isolation. They can work together, which is
+//! especially helpful if some arguments can be specified at compile-time while others must be
+//! specified at runtime.
+//!
+//! ### Using derived arguments in a builder application
+//!
+//! When using the derive API, you can `#[clap(flatten)]` a struct deriving `Args` into a struct
+//! deriving `Args` or `Parser`. This example shows how you can augment a `Command` instance
+//! created using the builder API with `Args` created using the derive API.
+//!
+//! It uses the [`Args::augment_args`][crate::Args::augment_args] method to add the arguments to
+//! the `Command` instance.
+//!
+//! Crates such as [clap-verbosity-flag](https://github.com/rust-cli/clap-verbosity-flag) provide
+//! structs that implement `Args`. Without the technique shown in this example, it would not be
+//! possible to use such crates with the builder API.
+//!
+//! For example:
+//! ```rust
+#![doc = include_str!("../../examples/derive_ref/augment_args.rs")]
+//! ```
+//!
+//! ### Using derived subcommands in a builder application
+//!
+//! When using the derive API, you can use `#[clap(subcommand)]` inside the struct to add
+//! subcommands. The type of the field is usually an enum that derived `Parser`. However, you can
+//! also add the subcommands in that enum to a `Command` instance created with the builder API.
+//!
+//! It uses the [`Subcommand::augment_subcommands`][crate::Subcommand::augment_subcommands] method
+//! to add the subcommands to the `Command` instance.
+//!
+//! For example:
+//! ```rust
+#![doc = include_str!("../../examples/derive_ref/augment_subcommands.rs")]
+//! ```
+//!
+//! ### Adding hand-implemented subcommands to a derived application
+//!
+//! When using the derive API, you can use `#[clap(subcommand)]` inside the struct to add
+//! subcommands. The type of the field is usually an enum that derived `Parser`. However, you can
+//! also implement the `Subcommand` trait manually on this enum (or any other type) and it can
+//! still be used inside the struct created with the derive API. The implementation of the
+//! `Subcommand` trait will use the builder API to add the subcommands to the `Command` instance
+//! created behind the scenes for you by the derive API.
+//!
+//! Notice how in the previous example we used
+//! [`augment_subcommands`][crate::Subcommand::augment_subcommands] on an enum that derived
+//! `Parser`, whereas now we implement
+//! [`augment_subcommands`][crate::Subcommand::augment_subcommands] ourselves, but the derive API
+//! calls it automatically since we used the `#[clap(subcommand)]` attribute.
+//!
+//! For example:
+//! ```rust
+#![doc = include_str!("../../examples/derive_ref/hand_subcommand.rs")]
+//! ```
+//!
+//! ### Flattening hand-implemented args into a derived application
+//!
+//! When using the derive API, you can use `#[clap(flatten)]` inside the struct to add arguments as
+//! if they were added directly to the containing struct. The type of the field is usually an
+//! struct that derived `Args`. However, you can also implement the `Args` trait manually on this
+//! struct (or any other type) and it can still be used inside the struct created with the derive
+//! API. The implementation of the `Args` trait will use the builder API to add the arguments to
+//! the `Command` instance created behind the scenes for you by the derive API.
+//!
+//! Notice how in the previous example we used [`augment_args`][crate::Args::augment_args] on the
+//! struct that derived `Parser`, whereas now we implement
+//! [`augment_args`][crate::Args::augment_args] ourselves, but the derive API calls it
+//! automatically since we used the `#[clap(flatten)]` attribute.
+//!
+//! For example:
+//! ```rust
+#![doc = include_str!("../../examples/derive_ref/flatten_hand_args.rs")]
+//! ```
+//!
+//! ## Tips
+//!
+//! - To get access to a [`Command`][crate::Command] call
+//!   [`CommandFactory::command`][crate::CommandFactory::command] (implemented when deriving
+//!   [`Parser`][crate::Parser])
+//! - Proactively check for bad [`Command`][crate::Command] configurations by calling
+//!   [`Command::debug_assert`][crate::App::debug_assert] in a test
+//!   ([example](../tutorial_derive/05_01_assert.rs))
+
+pub mod _tutorial;
+#[doc(inline)]
+pub use crate::_cookbook;
diff --git a/vendor/clap-3.2.20/src/_faq.rs b/vendor/clap-3.2.20/src/_faq.rs
new file mode 100644
index 000000000..661a7e73d
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_faq.rs
@@ -0,0 +1,95 @@
+//! # Documentation: FAQ
+//!
+//! 1. [Comparisons](#comparisons)
+//!    1. [How does `clap` compare to structopt?](#how-does-clap-compare-to-structopt)
+//!    2. [What are some reasons to use `clap`? (The Pitch)](#what-are-some-reasons-to-use-clap-the-pitch)
+//!    3. [What are some reasons *not* to use `clap`? (The Anti Pitch)](#what-are-some-reasons-not-to-use-clap-the-anti-pitch)
+//!    4. [Reasons to use `clap`](#reasons-to-use-clap)
+//! 2. [How many approaches are there to create a parser?](#how-many-approaches-are-there-to-create-a-parser)
+//! 3. [When should I use the builder vs derive APIs?](#when-should-i-use-the-builder-vs-derive-apis)
+//! 4. [Why is there a default subcommand of help?](#why-is-there-a-default-subcommand-of-help)
+//!
+//! ### Comparisons
+//!
+//! First, let me say that these comparisons are highly subjective, and not meant
+//! in a critical or harsh manner. All the argument parsing libraries out there (to
+//! include `clap`) have their own strengths and weaknesses. Sometimes it just
+//! comes down to personal taste when all other factors are equal. When in doubt,
+//! try them all and pick one that you enjoy :) There's plenty of room in the Rust
+//! community for multiple implementations!
+//!
+//! For less detailed but more broad comparisons, see
+//! [argparse-benchmarks](https://github.com/rust-cli/argparse-benchmarks-rs).
+//!
+//! #### How does `clap` compare to [structopt](https://github.com/TeXitoi/structopt)?
+//!
+//! Simple! `clap` *is* `structopt`.  `structopt` started as a derive API built on
+//! top of clap v2.  With clap v3, we've forked structopt and integrated it
+//! directly into clap.  structopt is in
+//! [maintenance mode](https://github.com/TeXitoi/structopt/issues/516#issuecomment-989566094)
+//! with the release of `clap_derive`.
+//!
+//! The benefits of integrating `structopt` and `clap` are:
+//! - Easier cross-linking in documentation
+//! - [Documentation parity](../examples)
+//! - Tighter design feedback loop, ensuring all new features are designed with
+//!   derives in mind and easier to change `clap` in response to `structopt` bugs.
+//! - Clearer endorsement of `structopt`
+//!
+//! See also
+//! - [`clap` v3 CHANGELOG](../CHANGELOG.md#300---2021-12-31)
+//! - [`structopt` migration guide](../CHANGELOG.md#migrate-structopt)
+//!
+//! #### What are some reasons to use `clap`? (The Pitch)
+//!
+//! `clap` is as fast, and as lightweight as possible while still giving all the features you'd expect from a modern argument parser. In fact, for the amount and type of features `clap` offers it remains about as fast as `getopts`. If you use `clap` when just need some simple arguments parsed, you'll find it's a walk in the park. `clap` also makes it possible to represent extremely complex, and advanced requirements, without too much thought. `clap` aims to be intuitive, easy to use, and fully capable for wide variety use cases and needs.
+//!
+//! #### What are some reasons *not* to use `clap`? (The Anti Pitch)
+//!
+//! Depending on the style in which you choose to define the valid arguments, `clap` can be very verbose. `clap` also offers so many finetuning knobs and dials, that learning everything can seem overwhelming. I strive to keep the simple cases simple, but when turning all those custom dials it can get complex. `clap` is also opinionated about parsing. Even though so much can be tweaked and tuned with `clap` (and I'm adding more all the time), there are still certain features which `clap` implements in specific ways which may be contrary to some users use-cases.
+//!
+//! #### Reasons to use `clap`
+//!
+//!  * You want all the nice CLI features your users may expect, yet you don't want to implement them all yourself. You'd like to focus your application, not argument parsing.
+//!  * In addition to the point above; you don't want to sacrifice performance to get all those nice features
+//!  * You have complex requirements/conflicts between your various valid args.
+//!  * You want to use subcommands (although other libraries also support subcommands, they are not nearly as feature rich as those provided by `clap`)
+//!  * You want some sort of custom validation built into the argument parsing process, instead of as part of your application (which allows for earlier failures, better error messages, more cohesive experience, etc.)
+//!
+//! ### How many approaches are there to create a parser?
+//!
+//! The following APIs are supported:
+//! - [Derive][crate::_derive::_tutorial]
+//! - [Builder][crate::_tutorial]
+//!
+//! Previously, we supported:
+//! - [YAML](https://github.com/clap-rs/clap/issues/3087)
+//! - [docopt](http://docopt.org/)-inspired [usage parser](https://github.com/clap-rs/clap/issues/3086)
+//! - [`clap_app!`](https://github.com/clap-rs/clap/issues/2835)
+//!
+//! There are also experiments with other APIs:
+//! - [fncmd](https://github.com/yuhr/fncmd): function attribute
+//! - [clap-serde](https://github.com/aobatact/clap-serde): create an `Command` from a deserializer
+//!
+//! ### When should I use the builder vs derive APIs?
+//!
+//! Our default answer is to use the [Derive API][crate::_derive::_tutorial]:
+//! - Easier to read, write, and modify
+//! - Easier to keep the argument declaration and reading of argument in sync
+//! - Easier to reuse, e.g. [clap-verbosity-flag](https://crates.io/crates/clap-verbosity-flag)
+//!
+//! The [Builder API][crate::_tutorial] is a lower-level API that someone might want to use for
+//! - Faster compile times if you aren't already using other procedural macros
+//! - More flexibility, e.g. you can look up an [arguments values][crate::ArgMatches::get_many],
+//!   their [ordering with other arguments][crate::ArgMatches::indices_of], and [what set
+//!   them][crate::ArgMatches::value_source].  The Derive API can only report values and not
+//!   indices of or other data.
+//!
+//! You can [interop between Derive and Builder APIs][crate::_derive#mixing-builder-and-derive-apis].
+//!
+//! ### Why is there a default subcommand of help?
+//!
+//! There is only a default subcommand of `help` when other subcommands have been defined manually. So it's opt-in(ish), being that you only get a `help` subcommand if you're actually using subcommands.
+//!
+//! Also, if the user defined a `help` subcommand themselves, the auto-generated one wouldn't be added (meaning it's only generated if the user hasn't defined one themselves).
+//!
diff --git a/vendor/clap-3.2.20/src/_features.rs b/vendor/clap-3.2.20/src/_features.rs
new file mode 100644
index 000000000..923134c45
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_features.rs
@@ -0,0 +1,27 @@
+//! ## Documentation: Feature Flags
+//!
+//! Available [compile-time feature flags](https://doc.rust-lang.org/cargo/reference/features.html#dependency-features)
+//!
+//! #### Default Features
+//!
+//! * **std**: _Not Currently Used._ Placeholder for supporting `no_std` environments in a backwards compatible manner.
+//! * **color**: Turns on colored error messages.
+//! * **suggestions**: Turns on the `Did you mean '--myoption'?` feature for when users make typos.
+//!
+//! #### Optional features
+//!
+//! * **deprecated**: Guided experience to prepare for next breaking release (at different stages of development, this may become default)
+//! * **derive**: Enables the custom derive (i.e. `#[derive(Parser)]`). Without this you must use one of the other methods of creating a `clap` CLI listed above.
+//! * **cargo**: Turns on macros that read values from [`CARGO_*` environment variables](https://doc.rust-lang.org/cargo/reference/environment-variables.html#environment-variables-cargo-sets-for-crates).
+//! * **env**: Turns on the usage of environment variables during parsing.
+//! * **regex**: Enables regex validators.
+//! * **unicode**: Turns on support for unicode characters (including emoji) in arguments and help messages.
+//! * **wrap_help**: Turns on the help text wrapping feature, based on the terminal size.
+//!
+//! #### Experimental features
+//!
+//! **Warning:** These may contain breaking changes between minor releases.
+//!
+//! * **unstable-replace**: Enable [`Command::replace`](https://github.com/clap-rs/clap/issues/2836)
+//! * **unstable-grouped**: Enable [`ArgMatches::grouped_values_of`](https://github.com/clap-rs/clap/issues/2924)
+//! * **unstable-v4**: Preview features which will be stable on the v4.0 release
diff --git a/vendor/clap-3.2.20/src/_tutorial.rs b/vendor/clap-3.2.20/src/_tutorial.rs
new file mode 100644
index 000000000..9dbfc6864
--- /dev/null
+++ b/vendor/clap-3.2.20/src/_tutorial.rs
@@ -0,0 +1,204 @@
+// Contributing
+//
+// New example code:
+// - Please update the corresponding section in the derive tutorial
+// - Building: They must be added to `Cargo.toml` with the appropriate `required-features`.
+// - Testing: Ensure there is a markdown file with [trycmd](https://docs.rs/trycmd) syntax
+//
+// See also the general CONTRIBUTING
+
+//! # Documentation: Builder Tutorial
+//!
+//! 1. [Quick Start](#quick-start)
+//! 2. [Configuring the Parser](#configuring-the-parser)
+//! 3. [Adding Arguments](#adding-arguments)
+//!     1. [Positionals](#positionals)
+//!     2. [Options](#options)
+//!     3. [Flags](#flags)
+//!     4. [Subcommands](#subcommands)
+//!     5. [Defaults](#defaults)
+//! 4. Validation
+//!     1. [Enumerated values](#enumerated-values)
+//!     2. [Validated values](#validated-values)
+//!     3. [Argument Relations](#argument-relations)
+//!     4. [Custom Validation](#custom-validation)
+//! 5. [Testing](#testing)
+//!
+//! See also
+//! - [FAQ: When should I use the builder vs derive APIs?][crate::_faq#when-should-i-use-the-builder-vs-derive-apis]
+//! - The [cookbook][crate::_cookbook] for more application-focused examples
+//!
+//! ## Quick Start
+//!
+//! You can create an application with several arguments using usage strings.
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/01_quick.rs")]
+//! ```
+//!
+#![doc = include_str!("../examples/tutorial_builder/01_quick.md")]
+//!
+//! ## Configuring the Parser
+//!
+//! You use [`Command`][crate::Command] to start building a parser.
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/02_apps.rs")]
+//! ```
+//!
+#![doc = include_str!("../examples/tutorial_builder/02_apps.md")]
+//!
+//! You can use [`command!()`][crate::command!] to fill these fields in from your `Cargo.toml`
+//! file.  **This requires the [`cargo` feature flag][crate::_features].**
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/02_crate.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/02_crate.md")]
+//!
+//! You can use [`Command`][crate::Command] methods to change the application level behavior of
+//! clap.
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/02_app_settings.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/02_app_settings.md")]
+//!
+//! ## Adding Arguments
+//!
+//! ### Positionals
+//!
+//! You can have users specify values by their position on the command-line:
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/03_03_positional.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/03_03_positional.md")]
+//!
+//! ### Options
+//!
+//! You can name your arguments with a flag:
+//! - Order doesn't matter
+//! - They can be optional
+//! - Intent is clearer
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/03_02_option.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/03_02_option.md")]
+//!
+//! ### Flags
+//!
+//! Flags can also be switches that can be on/off:
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/03_01_flag_bool.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/03_01_flag_bool.md")]
+//!
+//! Or counted.
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/03_01_flag_count.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/03_01_flag_count.md")]
+//!
+//! ### Subcommands
+//!
+//! Subcommands are defined as [`Command`][crate::Command]s that get added via
+//! [`Command::subcommand`][crate::Command::subcommand]. Each instance of a Subcommand can have its
+//! own version, author(s), Args, and even its own subcommands.
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/03_04_subcommands.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/03_04_subcommands.md")]
+//!
+//! ### Defaults
+//!
+//! We've previously showed that arguments can be [`required`][crate::Arg::required] or optional.
+//! When optional, you work with a `Option` and can `unwrap_or`.  Alternatively, you can set
+//! [`Arg::default_value`][crate::Arg::default_value].
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/03_05_default_values.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/03_05_default_values.md")]
+//!
+//! ## Validation
+//!
+//! ### Enumerated values
+//!
+//! If you have arguments of specific values you want to test for, you can use the
+//! [`PossibleValuesParser`][crate::builder::PossibleValuesParser] or [`Arg::value_parser(["val1",
+//! ...])`][crate::Arg::value_parser] for short.
+//!
+//! This allows you specify the valid values for that argument. If the user does not use one of
+//! those specific values, they will receive a graceful exit with error message informing them
+//! of the mistake, and what the possible valid values are
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/04_01_possible.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/04_01_possible.md")]
+//!
+//! When enabling the [`derive` feature][crate::_features], you can use
+//! [`ValueEnum`][crate::ValueEnum] to take care of the boiler plate for you, giving the same
+//! results.
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/04_01_enum.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/04_01_enum.md")]
+//!
+//! ### Validated values
+//!
+//! More generally, you can validate and parse into any data type.
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/04_02_parse.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/04_02_parse.md")]
+//!
+//! A custom parser can be used to improve the error messages or provide additional validation:
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/04_02_validate.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/04_02_validate.md")]
+//!
+//! ### Argument Relations
+//!
+//! You can declare dependencies or conflicts between [`Arg`][crate::Arg]s or even
+//! [`ArgGroup`][crate::ArgGroup]s.
+//!
+//! [`ArgGroup`][crate::ArgGroup]s  make it easier to declare relations instead of having to list
+//! each individually, or when you want a rule to apply "any but not all" arguments.
+//!
+//! Perhaps the most common use of [`ArgGroup`][crate::ArgGroup]s is to require one and *only* one
+//! argument to be present out of a given set. Imagine that you had multiple arguments, and you
+//! want one of them to be required, but making all of them required isn't feasible because perhaps
+//! they conflict with each other.
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/04_03_relations.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/04_03_relations.md")]
+//!
+//! ### Custom Validation
+//!
+//! As a last resort, you can create custom errors with the basics of clap's formatting.
+//!
+//! ```rust
+#![doc = include_str!("../examples/tutorial_builder/04_04_custom.rs")]
+//! ```
+#![doc = include_str!("../examples/tutorial_builder/04_04_custom.md")]
+//!
+//! ## Testing
+//!
+//! clap reports most development errors as `debug_assert!`s.  Rather than checking every
+//! subcommand, you should have a test that calls
+//! [`Command::debug_assert`][crate::App::debug_assert]:
+//! ```rust,no_run
+#![doc = include_str!("../examples/tutorial_builder/05_01_assert.rs")]
+//! ```
diff --git a/vendor/clap-3.2.20/src/bin/stdio-fixture.rs b/vendor/clap-3.2.20/src/bin/stdio-fixture.rs
new file mode 100644
index 000000000..e3f34b41a
--- /dev/null
+++ b/vendor/clap-3.2.20/src/bin/stdio-fixture.rs
@@ -0,0 +1,14 @@
+fn main() {
+    let cmd = clap::Command::new("stdio-fixture")
+        .version("1.0")
+        .long_version("1.0 - a2132c")
+        .arg_required_else_help(true)
+        .subcommand(clap::Command::new("more"))
+        .arg(
+            clap::Arg::new("verbose")
+                .long("verbose")
+                .help("log")
+                .long_help("more log"),
+        );
+    cmd.get_matches();
+}
diff --git a/vendor/clap-3.2.20/src/builder/action.rs b/vendor/clap-3.2.20/src/builder/action.rs
new file mode 100644
index 000000000..71a91a8b1
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/action.rs
@@ -0,0 +1,325 @@
+/// Behavior of arguments when they are encountered while parsing
+///
+/// # Examples
+///
+/// ```rust
+/// # use clap::Command;
+/// # use clap::Arg;
+/// let cmd = Command::new("mycmd")
+///     .arg(
+///         Arg::new("special-help")
+///             .short('?')
+///             .action(clap::ArgAction::Help)
+///     );
+///
+/// // Existing help still exists
+/// let err = cmd.clone().try_get_matches_from(["mycmd", "-h"]).unwrap_err();
+/// assert_eq!(err.kind(), clap::error::ErrorKind::DisplayHelp);
+///
+/// // New help available
+/// let err = cmd.try_get_matches_from(["mycmd", "-?"]).unwrap_err();
+/// assert_eq!(err.kind(), clap::error::ErrorKind::DisplayHelp);
+/// ```
+#[derive(Clone, Debug)]
+#[non_exhaustive]
+#[allow(missing_copy_implementations)] // In the future, we may accept `Box<dyn ...>`
+pub enum ArgAction {
+    /// When encountered, store the associated value(s) in [`ArgMatches`][crate::ArgMatches]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .arg(
+    ///         Arg::new("flag")
+    ///             .long("flag")
+    ///             .action(clap::ArgAction::Set)
+    ///     );
+    ///
+    /// let matches = cmd.try_get_matches_from(["mycmd", "--flag", "value"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(matches.occurrences_of("flag"), 0);
+    /// assert_eq!(
+    ///     matches.get_many::<String>("flag").unwrap_or_default().map(|v| v.as_str()).collect::<Vec<_>>(),
+    ///     vec!["value"]
+    /// );
+    /// ```
+    Set,
+    /// When encountered, store the associated value(s) in [`ArgMatches`][crate::ArgMatches]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .arg(
+    ///         Arg::new("flag")
+    ///             .long("flag")
+    ///             .action(clap::ArgAction::Append)
+    ///     );
+    ///
+    /// let matches = cmd.try_get_matches_from(["mycmd", "--flag", "value1", "--flag", "value2"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(matches.occurrences_of("flag"), 0);
+    /// assert_eq!(
+    ///     matches.get_many::<String>("flag").unwrap_or_default().map(|v| v.as_str()).collect::<Vec<_>>(),
+    ///     vec!["value1", "value2"]
+    /// );
+    /// ```
+    Append,
+    /// Deprecated, replaced with [`ArgAction::Set`] or [`ArgAction::Append`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Replaced with `ArgAction::Set` or `ArgAction::Append`"
+        )
+    )]
+    StoreValue,
+    /// Deprecated, replaced with [`ArgAction::SetTrue`] or [`ArgAction::Count`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Replaced with `ArgAction::SetTrue` or `ArgAction::Count`"
+        )
+    )]
+    IncOccurrence,
+    /// When encountered, act as if `"true"` was encountered on the command-line
+    ///
+    /// If no [`default_value`][super::Arg::default_value] is set, it will be `false`.
+    ///
+    /// No value is allowed. To optionally accept a value, see
+    /// [`Arg::default_missing_value`][super::Arg::default_missing_value]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .arg(
+    ///         Arg::new("flag")
+    ///             .long("flag")
+    ///             .action(clap::ArgAction::SetTrue)
+    ///     );
+    ///
+    /// let matches = cmd.clone().try_get_matches_from(["mycmd", "--flag", "--flag"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(matches.occurrences_of("flag"), 0);
+    /// assert_eq!(
+    ///     matches.get_one::<bool>("flag").copied(),
+    ///     Some(true)
+    /// );
+    ///
+    /// let matches = cmd.try_get_matches_from(["mycmd"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(matches.occurrences_of("flag"), 0);
+    /// assert_eq!(
+    ///     matches.get_one::<bool>("flag").copied(),
+    ///     Some(false)
+    /// );
+    /// ```
+    SetTrue,
+    /// When encountered, act as if `"false"` was encountered on the command-line
+    ///
+    /// If no [`default_value`][super::Arg::default_value] is set, it will be `true`.
+    ///
+    /// No value is allowed. To optionally accept a value, see
+    /// [`Arg::default_missing_value`][super::Arg::default_missing_value]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .arg(
+    ///         Arg::new("flag")
+    ///             .long("flag")
+    ///             .action(clap::ArgAction::SetFalse)
+    ///     );
+    ///
+    /// let matches = cmd.clone().try_get_matches_from(["mycmd", "--flag", "--flag"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(matches.occurrences_of("flag"), 0);
+    /// assert_eq!(
+    ///     matches.get_one::<bool>("flag").copied(),
+    ///     Some(false)
+    /// );
+    ///
+    /// let matches = cmd.try_get_matches_from(["mycmd"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(matches.occurrences_of("flag"), 0);
+    /// assert_eq!(
+    ///     matches.get_one::<bool>("flag").copied(),
+    ///     Some(true)
+    /// );
+    /// ```
+    SetFalse,
+    /// When encountered, increment a `u8` counter
+    ///
+    /// If no [`default_value`][super::Arg::default_value] is set, it will be `0`.
+    ///
+    /// No value is allowed. To optionally accept a value, see
+    /// [`Arg::default_missing_value`][super::Arg::default_missing_value]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .arg(
+    ///         Arg::new("flag")
+    ///             .long("flag")
+    ///             .action(clap::ArgAction::Count)
+    ///     );
+    ///
+    /// let matches = cmd.clone().try_get_matches_from(["mycmd", "--flag", "--flag"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(matches.occurrences_of("flag"), 0);
+    /// assert_eq!(
+    ///     matches.get_count("flag"),
+    ///     2
+    /// );
+    ///
+    /// let matches = cmd.try_get_matches_from(["mycmd"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(matches.occurrences_of("flag"), 0);
+    /// assert_eq!(
+    ///     matches.get_count("flag"),
+    ///     0
+    /// );
+    /// ```
+    Count,
+    /// When encountered, display [`Command::print_help`][super::App::print_help]
+    ///
+    /// Depending on the flag, [`Command::print_long_help`][super::App::print_long_help] may be shown
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .arg(
+    ///         Arg::new("special-help")
+    ///             .short('?')
+    ///             .action(clap::ArgAction::Help)
+    ///     );
+    ///
+    /// // Existing help still exists
+    /// let err = cmd.clone().try_get_matches_from(["mycmd", "-h"]).unwrap_err();
+    /// assert_eq!(err.kind(), clap::error::ErrorKind::DisplayHelp);
+    ///
+    /// // New help available
+    /// let err = cmd.try_get_matches_from(["mycmd", "-?"]).unwrap_err();
+    /// assert_eq!(err.kind(), clap::error::ErrorKind::DisplayHelp);
+    /// ```
+    Help,
+    /// When encountered, display [`Command::version`][super::App::version]
+    ///
+    /// Depending on the flag, [`Command::long_version`][super::App::long_version] may be shown
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .version("1.0.0")
+    ///     .arg(
+    ///         Arg::new("special-version")
+    ///             .long("special-version")
+    ///             .action(clap::ArgAction::Version)
+    ///     );
+    ///
+    /// // Existing help still exists
+    /// let err = cmd.clone().try_get_matches_from(["mycmd", "--version"]).unwrap_err();
+    /// assert_eq!(err.kind(), clap::error::ErrorKind::DisplayVersion);
+    ///
+    /// // New help available
+    /// let err = cmd.try_get_matches_from(["mycmd", "--special-version"]).unwrap_err();
+    /// assert_eq!(err.kind(), clap::error::ErrorKind::DisplayVersion);
+    /// ```
+    Version,
+}
+
+impl ArgAction {
+    /// Returns whether this action accepts values on the command-line
+    ///
+    /// [`default_values`][super::Arg::default_values] and [`env`][super::Arg::env] may still be
+    /// processed.
+    pub fn takes_values(&self) -> bool {
+        match self {
+            Self::Set => true,
+            Self::Append => true,
+            #[allow(deprecated)]
+            Self::StoreValue => true,
+            #[allow(deprecated)]
+            Self::IncOccurrence => false,
+            Self::SetTrue => false,
+            Self::SetFalse => false,
+            Self::Count => false,
+            Self::Help => false,
+            Self::Version => false,
+        }
+    }
+
+    pub(crate) fn default_value(&self) -> Option<&'static std::ffi::OsStr> {
+        match self {
+            Self::Set => None,
+            Self::Append => None,
+            #[allow(deprecated)]
+            Self::StoreValue => None,
+            #[allow(deprecated)]
+            Self::IncOccurrence => None,
+            Self::SetTrue => Some(std::ffi::OsStr::new("false")),
+            Self::SetFalse => Some(std::ffi::OsStr::new("true")),
+            Self::Count => Some(std::ffi::OsStr::new("0")),
+            Self::Help => None,
+            Self::Version => None,
+        }
+    }
+
+    pub(crate) fn default_value_parser(&self) -> Option<super::ValueParser> {
+        match self {
+            Self::Set => None,
+            Self::Append => None,
+            #[allow(deprecated)]
+            Self::StoreValue => None,
+            #[allow(deprecated)]
+            Self::IncOccurrence => None,
+            Self::SetTrue => Some(super::ValueParser::bool()),
+            Self::SetFalse => Some(super::ValueParser::bool()),
+            Self::Count => Some(crate::value_parser!(u8).into()),
+            Self::Help => None,
+            Self::Version => None,
+        }
+    }
+
+    #[cfg(debug_assertions)]
+    pub(crate) fn value_type_id(&self) -> Option<crate::parser::AnyValueId> {
+        use crate::parser::AnyValueId;
+
+        match self {
+            Self::Set => None,
+            Self::Append => None,
+            #[allow(deprecated)]
+            Self::StoreValue => None,
+            #[allow(deprecated)]
+            Self::IncOccurrence => None,
+            Self::SetTrue => Some(AnyValueId::of::<bool>()),
+            Self::SetFalse => Some(AnyValueId::of::<bool>()),
+            Self::Count => Some(AnyValueId::of::<CountType>()),
+            Self::Help => None,
+            Self::Version => None,
+        }
+    }
+}
+
+pub(crate) type CountType = u8;
diff --git a/vendor/clap-3.2.20/src/builder/app_settings.rs b/vendor/clap-3.2.20/src/builder/app_settings.rs
new file mode 100644
index 000000000..88bc243c4
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/app_settings.rs
@@ -0,0 +1,864 @@
+#![allow(deprecated)]
+
+// Std
+use std::ops::BitOr;
+#[cfg(feature = "yaml")]
+use std::str::FromStr;
+
+#[allow(unused)]
+use crate::Arg;
+#[allow(unused)]
+use crate::Command;
+
+// Third party
+use bitflags::bitflags;
+
+#[doc(hidden)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+pub struct AppFlags(Flags);
+
+impl Default for AppFlags {
+    fn default() -> Self {
+        AppFlags(Flags::COLOR_AUTO)
+    }
+}
+
+/// Application level settings, which affect how [`Command`] operates
+///
+/// **NOTE:** When these settings are used, they apply only to current command, and are *not*
+/// propagated down or up through child or parent subcommands
+///
+/// [`Command`]: crate::Command
+#[derive(Debug, PartialEq, Copy, Clone)]
+#[non_exhaustive]
+pub enum AppSettings {
+    /// Deprecated, replaced with [`Command::ignore_errors`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Command::ignore_errors`")
+    )]
+    IgnoreErrors,
+
+    /// Deprecated, replace
+    /// ```rust,no_run
+    /// let cmd = clap::Command::new("cmd")
+    ///     .global_setting(clap::AppSettings::WaitOnError)
+    ///     .arg(clap::arg!(--flag));
+    /// let m = cmd.get_matches();
+    /// ```
+    /// with
+    /// ```rust
+    /// let cmd = clap::Command::new("cmd")
+    ///     .arg(clap::arg!(--flag));
+    /// let m = match cmd.try_get_matches() {
+    ///     Ok(m) => m,
+    ///     Err(err) => {
+    ///         if err.use_stderr() {
+    ///             let _ = err.print();
+    ///
+    ///             eprintln!("\nPress [ENTER] / [RETURN] to continue...");
+    ///             use std::io::BufRead;
+    ///             let mut s = String::new();
+    ///             let i = std::io::stdin();
+    ///             i.lock().read_line(&mut s).unwrap();
+    ///
+    ///             std::process::exit(2);
+    ///         } else {
+    ///             let _ = err.print();
+    ///             std::process::exit(0);
+    ///         }
+    ///     }
+    /// };
+    /// ```
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "See documentation for how to hand-implement this"
+        )
+    )]
+    WaitOnError,
+
+    /// Deprecated, replaced with [`Command::allow_hyphen_values`] and
+    /// [`Arg::is_allow_hyphen_values_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::allow_hyphen_values` and `Arg::is_allow_hyphen_values_set`"
+        )
+    )]
+    AllowHyphenValues,
+
+    /// Deprecated, replaced with [`Command::allow_negative_numbers`] and
+    /// [`Command::is_allow_negative_numbers_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::allow_negative_numbers` and `Command::is_allow_negative_numbers_set`"
+        )
+    )]
+    AllowNegativeNumbers,
+
+    /// Deprecated, replaced with [`Command::args_override_self`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Command::args_override_self`")
+    )]
+    AllArgsOverrideSelf,
+
+    /// Deprecated, replaced with [`Command::allow_missing_positional`] and
+    /// [`Command::is_allow_missing_positional_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::allow_missing_positional` and `Command::is_allow_missing_positional_set`"
+        )
+    )]
+    AllowMissingPositional,
+
+    /// Deprecated, replaced with [`Command::trailing_var_arg`] and [`Command::is_trailing_var_arg_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::trailing_var_arg` and `Command::is_trailing_var_arg_set`"
+        )
+    )]
+    TrailingVarArg,
+
+    /// Deprecated, replaced with [`Command::dont_delimit_trailing_values`] and
+    /// [`Command::is_dont_delimit_trailing_values_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::dont_delimit_trailing_values` and `Command::is_dont_delimit_trailing_values_set`"
+        )
+    )]
+    DontDelimitTrailingValues,
+
+    /// Deprecated, replaced with [`Command::infer_long_args`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Command::infer_long_args`")
+    )]
+    InferLongArgs,
+
+    /// Deprecated, replaced with [`Command::infer_subcommands`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Command::infer_subcommands`")
+    )]
+    InferSubcommands,
+
+    /// Deprecated, replaced with [`Command::subcommand_required`] and
+    /// [`Command::is_subcommand_required_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::subcommand_required` and `Command::is_subcommand_required_set`"
+        )
+    )]
+    SubcommandRequired,
+
+    /// Deprecated, replaced with [`Command::subcommand_required`] combined with
+    /// [`Command::arg_required_else_help`].
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::subcommand_required` combined with `Command::arg_required_else_help`"
+        )
+    )]
+    SubcommandRequiredElseHelp,
+
+    /// Deprecated, replaced with [`Command::allow_external_subcommands`] and
+    /// [`Command::is_allow_external_subcommands_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::allow_external_subcommands` and `Command::is_allow_external_subcommands_set`"
+        )
+    )]
+    AllowExternalSubcommands,
+
+    /// Deprecated, replaced with [`Command::multicall`] and [`Command::is_multicall_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::multicall` and `Command::is_multicall_set`"
+        )
+    )]
+    Multicall,
+
+    /// Deprecated, replaced with [`Command::allow_invalid_utf8_for_external_subcommands`] and [`Command::is_allow_invalid_utf8_for_external_subcommands_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::allow_invalid_utf8_for_external_subcommands` and `Command::is_allow_invalid_utf8_for_external_subcommands_set`"
+        )
+    )]
+    AllowInvalidUtf8ForExternalSubcommands,
+
+    /// Deprecated, this is now the default
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "This is now the default")
+    )]
+    UseLongFormatForHelpSubcommand,
+
+    /// Deprecated, replaced with [`Command::subcommand_negates_reqs`] and
+    /// [`Command::is_subcommand_negates_reqs_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::subcommand_negates_reqs` and `Command::is_subcommand_negates_reqs_set`"
+        )
+    )]
+    SubcommandsNegateReqs,
+
+    /// Deprecated, replaced with [`Command::args_conflicts_with_subcommands`] and
+    /// [`Command::is_args_conflicts_with_subcommands_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::args_conflicts_with_subcommands` and `Command::is_args_conflicts_with_subcommands_set`"
+        )
+    )]
+    ArgsNegateSubcommands,
+
+    /// Deprecated, replaced with [`Command::subcommand_precedence_over_arg`] and
+    /// [`Command::is_subcommand_precedence_over_arg_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::subcommand_precedence_over_arg` and `Command::is_subcommand_precedence_over_arg_set`"
+        )
+    )]
+    SubcommandPrecedenceOverArg,
+
+    /// Deprecated, replaced with [`Command::arg_required_else_help`] and
+    /// [`Command::is_arg_required_else_help_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::arg_required_else_help` and `Command::is_arg_required_else_help_set`"
+        )
+    )]
+    ArgRequiredElseHelp,
+
+    /// Displays the arguments and [`subcommands`] in the help message in the order that they were
+    /// declared in, and not alphabetically which is the default.
+    ///
+    /// To override the declaration order, see [`Arg::display_order`] and [`Command::display_order`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, AppSettings};
+    /// Command::new("myprog")
+    ///     .global_setting(AppSettings::DeriveDisplayOrder)
+    ///     .get_matches();
+    /// ```
+    ///
+    /// [`subcommands`]: crate::Command::subcommand()
+    /// [`Arg::display_order`]: crate::Arg::display_order
+    /// [`Command::display_order`]: crate::Command::display_order
+    DeriveDisplayOrder,
+
+    /// Deprecated, replaced with [`Command::dont_collapse_args_in_usage`] and
+    /// [`Command::is_dont_collapse_args_in_usage_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::dont_collapse_args_in_usage` and `Command::is_dont_collapse_args_in_usage_set`"
+        )
+    )]
+    DontCollapseArgsInUsage,
+
+    /// Deprecated, replaced with [`Command::next_line_help`] and [`Command::is_next_line_help_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::next_line_help` and `Command::is_next_line_help_set`"
+        )
+    )]
+    NextLineHelp,
+
+    /// Deprecated, replaced with [`Command::disable_colored_help`] and
+    /// [`Command::is_disable_colored_help_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::disable_colored_help` and `Command::is_disable_colored_help_set`"
+        )
+    )]
+    DisableColoredHelp,
+
+    /// Deprecated, replaced with [`Command::disable_help_flag`] and [`Command::is_disable_help_flag_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::disable_help_flag` and `Command::is_disable_help_flag_set`"
+        )
+    )]
+    DisableHelpFlag,
+
+    /// Deprecated, replaced with [`Command::disable_help_subcommand`] and
+    /// [`Command::is_disable_help_subcommand_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::disable_help_subcommand` and `Command::is_disable_help_subcommand_set`"
+        )
+    )]
+    DisableHelpSubcommand,
+
+    /// Deprecated, replaced with [`Command::disable_version_flag`] and
+    /// [`Command::is_disable_version_flag_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::disable_version_flag` and `Command::is_disable_version_flag_set`"
+        )
+    )]
+    DisableVersionFlag,
+
+    /// Deprecated, replaced with [`Command::propagate_version`] and [`Command::is_propagate_version_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::propagate_version` and `Command::is_propagate_version_set`"
+        )
+    )]
+    PropagateVersion,
+
+    /// Deprecated, replaced with [`Command::hide`] and [`Command::is_hide_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::hide` and `Command::is_hide_set`"
+        )
+    )]
+    Hidden,
+
+    /// Deprecated, replaced with [`Command::hide_possible_values`] and
+    /// [`Arg::is_hide_possible_values_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Command::hide_possible_values` and `Arg::is_hide_possible_values_set`"
+        )
+    )]
+    HidePossibleValues,
+
+    /// Deprecated, replaced with [`Command::help_expected`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Command::help_expected`")
+    )]
+    HelpExpected,
+
+    /// Deprecated, replaced with [`Command::no_binary_name`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Command::no_binary_name`")
+    )]
+    NoBinaryName,
+
+    /// Deprecated, replaced with [`Arg::action`][super::Arg::action]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `Arg::action`")
+    )]
+    NoAutoHelp,
+
+    /// Deprecated, replaced with [`Arg::action`][super::Arg::action]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `Arg::action`")
+    )]
+    NoAutoVersion,
+
+    /// Deprecated, replaced with [`Command::allow_hyphen_values`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Command::allow_hyphen_values`")
+    )]
+    #[doc(hidden)]
+    AllowLeadingHyphen,
+
+    /// Deprecated, replaced with [`Command::allow_invalid_utf8_for_external_subcommands`] and [`Command::is_allow_invalid_utf8_for_external_subcommands_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `Command::allow_invalid_utf8_for_external_subcommands` and `Command::is_allow_invalid_utf8_for_external_subcommands_set`"
+        )
+    )]
+    #[doc(hidden)]
+    StrictUtf8,
+
+    /// Deprecated, this is now the default
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "This is now the default")
+    )]
+    #[doc(hidden)]
+    UnifiedHelpMessage,
+
+    /// Deprecated, this is now the default
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "This is now the default")
+    )]
+    #[doc(hidden)]
+    ColoredHelp,
+
+    /// Deprecated, see [`Command::color`][crate::Command::color]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Command::color`")
+    )]
+    #[doc(hidden)]
+    ColorAuto,
+
+    /// Deprecated, replaced with [`Command::color`][crate::Command::color]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Command::color`")
+    )]
+    #[doc(hidden)]
+    ColorAlways,
+
+    /// Deprecated, replaced with [`Command::color`][crate::Command::color]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Command::color`")
+    )]
+    #[doc(hidden)]
+    ColorNever,
+
+    /// Deprecated, replaced with [`Command::disable_help_flag`] and [`Command::is_disable_help_flag_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `Command::disable_help_flag` and `Command::is_disable_help_flag_set`"
+        )
+    )]
+    #[doc(hidden)]
+    DisableHelpFlags,
+
+    /// Deprecated, replaced with [`Command::disable_version_flag`] and
+    /// [`Command::is_disable_version_flag_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `Command::disable_version_flag` and `Command::is_disable_version_flag_set`"
+        )
+    )]
+    #[doc(hidden)]
+    DisableVersion,
+
+    /// Deprecated, replaced with [`Command::propagate_version`] and [`Command::is_propagate_version_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `Command::propagate_version` and `Command::is_propagate_version_set`"
+        )
+    )]
+    #[doc(hidden)]
+    GlobalVersion,
+
+    /// Deprecated, replaced with [`Command::hide_possible_values`] and
+    /// [`Arg::is_hide_possible_values_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `Command::hide_possible_values` and `Arg::is_hide_possible_values_set`"
+        )
+    )]
+    #[doc(hidden)]
+    HidePossibleValuesInHelp,
+
+    /// Deprecated, this is now the default
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "This is now the default")
+    )]
+    #[doc(hidden)]
+    UnifiedHelp,
+
+    /// If the cmd is already built, used for caching.
+    #[doc(hidden)]
+    Built,
+
+    /// If the cmd's bin name is already built, used for caching.
+    #[doc(hidden)]
+    BinNameBuilt,
+}
+
+bitflags! {
+    struct Flags: u64 {
+        const SC_NEGATE_REQS                 = 1;
+        const SC_REQUIRED                    = 1 << 1;
+        const ARG_REQUIRED_ELSE_HELP         = 1 << 2;
+        const PROPAGATE_VERSION              = 1 << 3;
+        const DISABLE_VERSION_FOR_SC         = 1 << 4;
+        const WAIT_ON_ERROR                  = 1 << 6;
+        const SC_REQUIRED_ELSE_HELP          = 1 << 7;
+        const NO_AUTO_HELP                   = 1 << 8;
+        const NO_AUTO_VERSION                = 1 << 9;
+        const DISABLE_VERSION_FLAG           = 1 << 10;
+        const HIDDEN                         = 1 << 11;
+        const TRAILING_VARARG                = 1 << 12;
+        const NO_BIN_NAME                    = 1 << 13;
+        const ALLOW_UNK_SC                   = 1 << 14;
+        const SC_UTF8_NONE                   = 1 << 15;
+        const LEADING_HYPHEN                 = 1 << 16;
+        const NO_POS_VALUES                  = 1 << 17;
+        const NEXT_LINE_HELP                 = 1 << 18;
+        const DERIVE_DISP_ORDER              = 1 << 19;
+        const DISABLE_COLORED_HELP           = 1 << 20;
+        const COLOR_ALWAYS                   = 1 << 21;
+        const COLOR_AUTO                     = 1 << 22;
+        const COLOR_NEVER                    = 1 << 23;
+        const DONT_DELIM_TRAIL               = 1 << 24;
+        const ALLOW_NEG_NUMS                 = 1 << 25;
+        const DISABLE_HELP_SC                = 1 << 27;
+        const DONT_COLLAPSE_ARGS             = 1 << 28;
+        const ARGS_NEGATE_SCS                = 1 << 29;
+        const PROPAGATE_VALS_DOWN            = 1 << 30;
+        const ALLOW_MISSING_POS              = 1 << 31;
+        const TRAILING_VALUES                = 1 << 32;
+        const BUILT                          = 1 << 33;
+        const BIN_NAME_BUILT                 = 1 << 34;
+        const VALID_ARG_FOUND                = 1 << 35;
+        const INFER_SUBCOMMANDS              = 1 << 36;
+        const CONTAINS_LAST                  = 1 << 37;
+        const ARGS_OVERRIDE_SELF             = 1 << 38;
+        const HELP_REQUIRED                  = 1 << 39;
+        const SUBCOMMAND_PRECEDENCE_OVER_ARG = 1 << 40;
+        const DISABLE_HELP_FLAG              = 1 << 41;
+        const USE_LONG_FORMAT_FOR_HELP_SC    = 1 << 42;
+        const INFER_LONG_ARGS                = 1 << 43;
+        const IGNORE_ERRORS                  = 1 << 44;
+        const MULTICALL                      = 1 << 45;
+        const NO_OP                          = 0;
+    }
+}
+
+impl_settings! { AppSettings, AppFlags,
+    ArgRequiredElseHelp
+        => Flags::ARG_REQUIRED_ELSE_HELP,
+    SubcommandPrecedenceOverArg
+        => Flags::SUBCOMMAND_PRECEDENCE_OVER_ARG,
+    ArgsNegateSubcommands
+        => Flags::ARGS_NEGATE_SCS,
+    AllowExternalSubcommands
+        => Flags::ALLOW_UNK_SC,
+    StrictUtf8
+        => Flags::NO_OP,
+    AllowInvalidUtf8ForExternalSubcommands
+        => Flags::SC_UTF8_NONE,
+    AllowHyphenValues
+        => Flags::LEADING_HYPHEN,
+    AllowLeadingHyphen
+        => Flags::LEADING_HYPHEN,
+    AllowNegativeNumbers
+        => Flags::ALLOW_NEG_NUMS,
+    AllowMissingPositional
+        => Flags::ALLOW_MISSING_POS,
+    UnifiedHelpMessage
+        => Flags::NO_OP,
+    ColoredHelp
+        => Flags::NO_OP,
+    ColorAlways
+        => Flags::COLOR_ALWAYS,
+    ColorAuto
+        => Flags::COLOR_AUTO,
+    ColorNever
+        => Flags::COLOR_NEVER,
+    DontDelimitTrailingValues
+        => Flags::DONT_DELIM_TRAIL,
+    DontCollapseArgsInUsage
+        => Flags::DONT_COLLAPSE_ARGS,
+    DeriveDisplayOrder
+        => Flags::DERIVE_DISP_ORDER,
+    DisableColoredHelp
+        => Flags::DISABLE_COLORED_HELP,
+    DisableHelpSubcommand
+        => Flags::DISABLE_HELP_SC,
+    DisableHelpFlag
+        => Flags::DISABLE_HELP_FLAG,
+    DisableHelpFlags
+        => Flags::DISABLE_HELP_FLAG,
+    DisableVersionFlag
+        => Flags::DISABLE_VERSION_FLAG,
+    DisableVersion
+        => Flags::DISABLE_VERSION_FLAG,
+    PropagateVersion
+        => Flags::PROPAGATE_VERSION,
+    GlobalVersion
+        => Flags::PROPAGATE_VERSION,
+    HidePossibleValues
+        => Flags::NO_POS_VALUES,
+    HidePossibleValuesInHelp
+        => Flags::NO_POS_VALUES,
+    HelpExpected
+        => Flags::HELP_REQUIRED,
+    Hidden
+        => Flags::HIDDEN,
+    Multicall
+        => Flags::MULTICALL,
+    NoAutoHelp
+        => Flags::NO_AUTO_HELP,
+    NoAutoVersion
+        => Flags::NO_AUTO_VERSION,
+    NoBinaryName
+        => Flags::NO_BIN_NAME,
+    SubcommandsNegateReqs
+        => Flags::SC_NEGATE_REQS,
+    SubcommandRequired
+        => Flags::SC_REQUIRED,
+    SubcommandRequiredElseHelp
+        => Flags::SC_REQUIRED_ELSE_HELP,
+    UseLongFormatForHelpSubcommand
+        => Flags::USE_LONG_FORMAT_FOR_HELP_SC,
+    TrailingVarArg
+        => Flags::TRAILING_VARARG,
+    UnifiedHelp => Flags::NO_OP,
+    NextLineHelp
+        => Flags::NEXT_LINE_HELP,
+    IgnoreErrors
+        => Flags::IGNORE_ERRORS,
+    WaitOnError
+        => Flags::WAIT_ON_ERROR,
+    Built
+        => Flags::BUILT,
+    BinNameBuilt
+        => Flags::BIN_NAME_BUILT,
+    InferSubcommands
+        => Flags::INFER_SUBCOMMANDS,
+    AllArgsOverrideSelf
+        => Flags::ARGS_OVERRIDE_SELF,
+    InferLongArgs
+        => Flags::INFER_LONG_ARGS
+}
+
+/// Deprecated in [Issue #3087](https://github.com/clap-rs/clap/issues/3087), maybe [`clap::Parser`][crate::Parser] would fit your use case?
+#[cfg(feature = "yaml")]
+impl FromStr for AppSettings {
+    type Err = String;
+    fn from_str(s: &str) -> Result<Self, <Self as FromStr>::Err> {
+        #[allow(deprecated)]
+        #[allow(unreachable_patterns)]
+        match &*s.to_ascii_lowercase() {
+            "argrequiredelsehelp" => Ok(AppSettings::ArgRequiredElseHelp),
+            "subcommandprecedenceoverarg" => Ok(AppSettings::SubcommandPrecedenceOverArg),
+            "argsnegatesubcommands" => Ok(AppSettings::ArgsNegateSubcommands),
+            "allowexternalsubcommands" => Ok(AppSettings::AllowExternalSubcommands),
+            "strictutf8" => Ok(AppSettings::StrictUtf8),
+            "allowinvalidutf8forexternalsubcommands" => {
+                Ok(AppSettings::AllowInvalidUtf8ForExternalSubcommands)
+            }
+            "allowhyphenvalues" => Ok(AppSettings::AllowHyphenValues),
+            "allowleadinghyphen" => Ok(AppSettings::AllowLeadingHyphen),
+            "allownegativenumbers" => Ok(AppSettings::AllowNegativeNumbers),
+            "allowmissingpositional" => Ok(AppSettings::AllowMissingPositional),
+            "unifiedhelpmessage" => Ok(AppSettings::UnifiedHelpMessage),
+            "coloredhelp" => Ok(AppSettings::ColoredHelp),
+            "coloralways" => Ok(AppSettings::ColorAlways),
+            "colorauto" => Ok(AppSettings::ColorAuto),
+            "colornever" => Ok(AppSettings::ColorNever),
+            "dontdelimittrailingvalues" => Ok(AppSettings::DontDelimitTrailingValues),
+            "dontcollapseargsinusage" => Ok(AppSettings::DontCollapseArgsInUsage),
+            "derivedisplayorder" => Ok(AppSettings::DeriveDisplayOrder),
+            "disablecoloredhelp" => Ok(AppSettings::DisableColoredHelp),
+            "disablehelpsubcommand" => Ok(AppSettings::DisableHelpSubcommand),
+            "disablehelpflag" => Ok(AppSettings::DisableHelpFlag),
+            "disablehelpflags" => Ok(AppSettings::DisableHelpFlags),
+            "disableversionflag" => Ok(AppSettings::DisableVersionFlag),
+            "disableversion" => Ok(AppSettings::DisableVersion),
+            "propagateversion" => Ok(AppSettings::PropagateVersion),
+            "propagateversion" => Ok(AppSettings::GlobalVersion),
+            "hidepossiblevalues" => Ok(AppSettings::HidePossibleValues),
+            "hidepossiblevaluesinhelp" => Ok(AppSettings::HidePossibleValuesInHelp),
+            "helpexpected" => Ok(AppSettings::HelpExpected),
+            "hidden" => Ok(AppSettings::Hidden),
+            "noautohelp" => Ok(AppSettings::NoAutoHelp),
+            "noautoversion" => Ok(AppSettings::NoAutoVersion),
+            "nobinaryname" => Ok(AppSettings::NoBinaryName),
+            "subcommandsnegatereqs" => Ok(AppSettings::SubcommandsNegateReqs),
+            "subcommandrequired" => Ok(AppSettings::SubcommandRequired),
+            "subcommandrequiredelsehelp" => Ok(AppSettings::SubcommandRequiredElseHelp),
+            "uselongformatforhelpsubcommand" => Ok(AppSettings::UseLongFormatForHelpSubcommand),
+            "trailingvararg" => Ok(AppSettings::TrailingVarArg),
+            "unifiedhelp" => Ok(AppSettings::UnifiedHelp),
+            "nextlinehelp" => Ok(AppSettings::NextLineHelp),
+            "ignoreerrors" => Ok(AppSettings::IgnoreErrors),
+            "waitonerror" => Ok(AppSettings::WaitOnError),
+            "built" => Ok(AppSettings::Built),
+            "binnamebuilt" => Ok(AppSettings::BinNameBuilt),
+            "infersubcommands" => Ok(AppSettings::InferSubcommands),
+            "allargsoverrideself" => Ok(AppSettings::AllArgsOverrideSelf),
+            "inferlongargs" => Ok(AppSettings::InferLongArgs),
+            _ => Err(format!("unknown AppSetting: `{}`", s)),
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    #[allow(clippy::cognitive_complexity)]
+    #[test]
+    #[cfg(feature = "yaml")]
+    fn app_settings_fromstr() {
+        use super::AppSettings;
+
+        assert_eq!(
+            "disablehelpflag".parse::<AppSettings>().unwrap(),
+            AppSettings::DisableHelpFlag
+        );
+        assert_eq!(
+            "argsnegatesubcommands".parse::<AppSettings>().unwrap(),
+            AppSettings::ArgsNegateSubcommands
+        );
+        assert_eq!(
+            "argrequiredelsehelp".parse::<AppSettings>().unwrap(),
+            AppSettings::ArgRequiredElseHelp
+        );
+        assert_eq!(
+            "subcommandprecedenceoverarg"
+                .parse::<AppSettings>()
+                .unwrap(),
+            AppSettings::SubcommandPrecedenceOverArg
+        );
+        assert_eq!(
+            "allowexternalsubcommands".parse::<AppSettings>().unwrap(),
+            AppSettings::AllowExternalSubcommands
+        );
+        assert_eq!(
+            "allowinvalidutf8forexternalsubcommands"
+                .parse::<AppSettings>()
+                .unwrap(),
+            AppSettings::AllowInvalidUtf8ForExternalSubcommands
+        );
+        assert_eq!(
+            "allowhyphenvalues".parse::<AppSettings>().unwrap(),
+            AppSettings::AllowHyphenValues
+        );
+        assert_eq!(
+            "allownegativenumbers".parse::<AppSettings>().unwrap(),
+            AppSettings::AllowNegativeNumbers
+        );
+        assert_eq!(
+            "disablehelpsubcommand".parse::<AppSettings>().unwrap(),
+            AppSettings::DisableHelpSubcommand
+        );
+        assert_eq!(
+            "disableversionflag".parse::<AppSettings>().unwrap(),
+            AppSettings::DisableVersionFlag
+        );
+        assert_eq!(
+            "dontcollapseargsinusage".parse::<AppSettings>().unwrap(),
+            AppSettings::DontCollapseArgsInUsage
+        );
+        assert_eq!(
+            "dontdelimittrailingvalues".parse::<AppSettings>().unwrap(),
+            AppSettings::DontDelimitTrailingValues
+        );
+        assert_eq!(
+            "derivedisplayorder".parse::<AppSettings>().unwrap(),
+            AppSettings::DeriveDisplayOrder
+        );
+        assert_eq!(
+            "disablecoloredhelp".parse::<AppSettings>().unwrap(),
+            AppSettings::DisableColoredHelp
+        );
+        assert_eq!(
+            "propagateversion".parse::<AppSettings>().unwrap(),
+            AppSettings::PropagateVersion
+        );
+        assert_eq!(
+            "hidden".parse::<AppSettings>().unwrap(),
+            AppSettings::Hidden
+        );
+        assert_eq!(
+            "hidepossiblevalues".parse::<AppSettings>().unwrap(),
+            AppSettings::HidePossibleValues
+        );
+        assert_eq!(
+            "helpexpected".parse::<AppSettings>().unwrap(),
+            AppSettings::HelpExpected
+        );
+        assert_eq!(
+            "nobinaryname".parse::<AppSettings>().unwrap(),
+            AppSettings::NoBinaryName
+        );
+        assert_eq!(
+            "nextlinehelp".parse::<AppSettings>().unwrap(),
+            AppSettings::NextLineHelp
+        );
+        assert_eq!(
+            "subcommandsnegatereqs".parse::<AppSettings>().unwrap(),
+            AppSettings::SubcommandsNegateReqs
+        );
+        assert_eq!(
+            "subcommandrequired".parse::<AppSettings>().unwrap(),
+            AppSettings::SubcommandRequired
+        );
+        assert_eq!(
+            "subcommandrequiredelsehelp".parse::<AppSettings>().unwrap(),
+            AppSettings::SubcommandRequiredElseHelp
+        );
+        assert_eq!(
+            "uselongformatforhelpsubcommand"
+                .parse::<AppSettings>()
+                .unwrap(),
+            AppSettings::UseLongFormatForHelpSubcommand
+        );
+        assert_eq!(
+            "trailingvararg".parse::<AppSettings>().unwrap(),
+            AppSettings::TrailingVarArg
+        );
+        assert_eq!(
+            "waitonerror".parse::<AppSettings>().unwrap(),
+            AppSettings::WaitOnError
+        );
+        assert_eq!("built".parse::<AppSettings>().unwrap(), AppSettings::Built);
+        assert_eq!(
+            "binnamebuilt".parse::<AppSettings>().unwrap(),
+            AppSettings::BinNameBuilt
+        );
+        assert_eq!(
+            "infersubcommands".parse::<AppSettings>().unwrap(),
+            AppSettings::InferSubcommands
+        );
+        assert!("hahahaha".parse::<AppSettings>().is_err());
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/arg.rs b/vendor/clap-3.2.20/src/builder/arg.rs
new file mode 100644
index 000000000..e9403d0b7
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/arg.rs
@@ -0,0 +1,5494 @@
+#![allow(deprecated)]
+
+// Std
+use std::{
+    borrow::Cow,
+    cmp::{Ord, Ordering},
+    error::Error,
+    ffi::OsStr,
+    fmt::{self, Display, Formatter},
+    str,
+    sync::{Arc, Mutex},
+};
+#[cfg(feature = "env")]
+use std::{env, ffi::OsString};
+
+#[cfg(feature = "yaml")]
+use yaml_rust::Yaml;
+
+// Internal
+use crate::builder::usage_parser::UsageParser;
+use crate::builder::ArgPredicate;
+use crate::util::{Id, Key};
+use crate::ArgAction;
+use crate::PossibleValue;
+use crate::ValueHint;
+use crate::INTERNAL_ERROR_MSG;
+use crate::{ArgFlags, ArgSettings};
+
+#[cfg(feature = "regex")]
+use crate::builder::RegexRef;
+
+/// The abstract representation of a command line argument. Used to set all the options and
+/// relationships that define a valid argument for the program.
+///
+/// There are two methods for constructing [`Arg`]s, using the builder pattern and setting options
+/// manually, or using a usage string which is far less verbose but has fewer options. You can also
+/// use a combination of the two methods to achieve the best of both worlds.
+///
+/// - [Basic API][crate::Arg#basic-api]
+/// - [Value Handling][crate::Arg#value-handling]
+/// - [Help][crate::Arg#help-1]
+/// - [Advanced Argument Relations][crate::Arg#advanced-argument-relations]
+/// - [Reflection][crate::Arg#reflection]
+///
+/// # Examples
+///
+/// ```rust
+/// # use clap::{Arg, arg};
+/// // Using the traditional builder pattern and setting each option manually
+/// let cfg = Arg::new("config")
+///       .short('c')
+///       .long("config")
+///       .takes_value(true)
+///       .value_name("FILE")
+///       .help("Provides a config file to myprog");
+/// // Using a usage string (setting a similar argument to the one above)
+/// let input = arg!(-i --input <FILE> "Provides an input file to the program");
+/// ```
+#[allow(missing_debug_implementations)]
+#[derive(Default, Clone)]
+pub struct Arg<'help> {
+    pub(crate) id: Id,
+    pub(crate) provider: ArgProvider,
+    pub(crate) name: &'help str,
+    pub(crate) help: Option<&'help str>,
+    pub(crate) long_help: Option<&'help str>,
+    pub(crate) action: Option<ArgAction>,
+    pub(crate) value_parser: Option<super::ValueParser>,
+    pub(crate) blacklist: Vec<Id>,
+    pub(crate) settings: ArgFlags,
+    pub(crate) overrides: Vec<Id>,
+    pub(crate) groups: Vec<Id>,
+    pub(crate) requires: Vec<(ArgPredicate<'help>, Id)>,
+    pub(crate) r_ifs: Vec<(Id, &'help str)>,
+    pub(crate) r_ifs_all: Vec<(Id, &'help str)>,
+    pub(crate) r_unless: Vec<Id>,
+    pub(crate) r_unless_all: Vec<Id>,
+    pub(crate) short: Option<char>,
+    pub(crate) long: Option<&'help str>,
+    pub(crate) aliases: Vec<(&'help str, bool)>, // (name, visible)
+    pub(crate) short_aliases: Vec<(char, bool)>, // (name, visible)
+    pub(crate) disp_ord: DisplayOrder,
+    pub(crate) possible_vals: Vec<PossibleValue<'help>>,
+    pub(crate) val_names: Vec<&'help str>,
+    pub(crate) num_vals: Option<usize>,
+    pub(crate) max_occurs: Option<usize>,
+    pub(crate) max_vals: Option<usize>,
+    pub(crate) min_vals: Option<usize>,
+    pub(crate) validator: Option<Arc<Mutex<Validator<'help>>>>,
+    pub(crate) validator_os: Option<Arc<Mutex<ValidatorOs<'help>>>>,
+    pub(crate) val_delim: Option<char>,
+    pub(crate) default_vals: Vec<&'help OsStr>,
+    pub(crate) default_vals_ifs: Vec<(Id, ArgPredicate<'help>, Option<&'help OsStr>)>,
+    pub(crate) default_missing_vals: Vec<&'help OsStr>,
+    #[cfg(feature = "env")]
+    pub(crate) env: Option<(&'help OsStr, Option<OsString>)>,
+    pub(crate) terminator: Option<&'help str>,
+    pub(crate) index: Option<usize>,
+    pub(crate) help_heading: Option<Option<&'help str>>,
+    pub(crate) value_hint: Option<ValueHint>,
+}
+
+/// # Basic API
+impl<'help> Arg<'help> {
+    /// Create a new [`Arg`] with a unique name.
+    ///
+    /// The name is used to check whether or not the argument was used at
+    /// runtime, get values, set relationships with other args, etc..
+    ///
+    /// **NOTE:** In the case of arguments that take values (i.e. [`Arg::takes_value(true)`])
+    /// and positional arguments (i.e. those without a preceding `-` or `--`) the name will also
+    /// be displayed when the user prints the usage/help information of the program.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("config")
+    /// # ;
+    /// ```
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    pub fn new<S: Into<&'help str>>(n: S) -> Self {
+        Arg::default().name(n)
+    }
+
+    /// Set the identifier used for referencing this argument in the clap API.
+    ///
+    /// See [`Arg::new`] for more details.
+    #[must_use]
+    pub fn id<S: Into<&'help str>>(mut self, n: S) -> Self {
+        let name = n.into();
+        self.id = Id::from(&*name);
+        self.name = name;
+        self
+    }
+
+    /// Deprecated, replaced with [`Arg::id`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Arg::id`")
+    )]
+    pub fn name<S: Into<&'help str>>(self, n: S) -> Self {
+        self.id(n)
+    }
+
+    /// Sets the short version of the argument without the preceding `-`.
+    ///
+    /// By default `V` and `h` are used by the auto-generated `version` and `help` arguments,
+    /// respectively. You may use the uppercase `V` or lowercase `h` for your own arguments, in
+    /// which case `clap` simply will not assign those to the auto-generated
+    /// `version` or `help` arguments.
+    ///
+    /// # Examples
+    ///
+    /// When calling `short`, use a single valid UTF-8 character which will allow using the
+    /// argument via a single hyphen (`-`) such as `-c`:
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("config")
+    ///         .short('c')
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-c", "file.toml"
+    ///     ]);
+    ///
+    /// assert_eq!(m.get_one::<String>("config").map(String::as_str), Some("file.toml"));
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn short(mut self, s: char) -> Self {
+        assert!(s != '-', "short option name cannot be `-`");
+
+        self.short = Some(s);
+        self
+    }
+
+    /// Sets the long version of the argument without the preceding `--`.
+    ///
+    /// By default `version` and `help` are used by the auto-generated `version` and `help`
+    /// arguments, respectively. You may use the word `version` or `help` for the long form of your
+    /// own arguments, in which case `clap` simply will not assign those to the auto-generated
+    /// `version` or `help` arguments.
+    ///
+    /// **NOTE:** Any leading `-` characters will be stripped
+    ///
+    /// # Examples
+    ///
+    /// To set `long` use a word containing valid UTF-8. If you supply a double leading
+    /// `--` such as `--config` they will be stripped. Hyphens in the middle of the word, however,
+    /// will *not* be stripped (i.e. `config-file` is allowed).
+    ///
+    /// Setting `long` allows using the argument via a double hyphen (`--`) such as `--config`
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .long("config")
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--config", "file.toml"
+    ///     ]);
+    ///
+    /// assert_eq!(m.get_one::<String>("cfg").map(String::as_str), Some("file.toml"));
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn long(mut self, l: &'help str) -> Self {
+        #[cfg(feature = "unstable-v4")]
+        {
+            self.long = Some(l);
+        }
+        #[cfg(not(feature = "unstable-v4"))]
+        {
+            self.long = Some(l.trim_start_matches(|c| c == '-'));
+        }
+        self
+    }
+
+    /// Add an alias, which functions as a hidden long flag.
+    ///
+    /// This is more efficient, and easier than creating multiple hidden arguments as one only
+    /// needs to check for the existence of this command, and not all variants.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///             .arg(Arg::new("test")
+    ///             .long("test")
+    ///             .alias("alias")
+    ///             .takes_value(true))
+    ///        .get_matches_from(vec![
+    ///             "prog", "--alias", "cool"
+    ///         ]);
+    /// assert!(m.contains_id("test"));
+    /// assert_eq!(m.value_of("test"), Some("cool"));
+    /// ```
+    #[must_use]
+    pub fn alias<S: Into<&'help str>>(mut self, name: S) -> Self {
+        self.aliases.push((name.into(), false));
+        self
+    }
+
+    /// Add an alias, which functions as a hidden short flag.
+    ///
+    /// This is more efficient, and easier than creating multiple hidden arguments as one only
+    /// needs to check for the existence of this command, and not all variants.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///             .arg(Arg::new("test")
+    ///             .short('t')
+    ///             .short_alias('e')
+    ///             .takes_value(true))
+    ///        .get_matches_from(vec![
+    ///             "prog", "-e", "cool"
+    ///         ]);
+    /// assert!(m.contains_id("test"));
+    /// assert_eq!(m.value_of("test"), Some("cool"));
+    /// ```
+    #[must_use]
+    pub fn short_alias(mut self, name: char) -> Self {
+        assert!(name != '-', "short alias name cannot be `-`");
+
+        self.short_aliases.push((name, false));
+        self
+    }
+
+    /// Add aliases, which function as hidden long flags.
+    ///
+    /// This is more efficient, and easier than creating multiple hidden subcommands as one only
+    /// needs to check for the existence of this command, and not all variants.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let m = Command::new("prog")
+    ///             .arg(Arg::new("test")
+    ///                     .long("test")
+    ///                     .aliases(&["do-stuff", "do-tests", "tests"])
+    ///                     .action(ArgAction::SetTrue)
+    ///                     .help("the file to add")
+    ///                     .required(false))
+    ///             .get_matches_from(vec![
+    ///                 "prog", "--do-tests"
+    ///             ]);
+    /// assert_eq!(*m.get_one::<bool>("test").expect("defaulted by clap"), true);
+    /// ```
+    #[must_use]
+    pub fn aliases(mut self, names: &[&'help str]) -> Self {
+        self.aliases.extend(names.iter().map(|&x| (x, false)));
+        self
+    }
+
+    /// Add aliases, which functions as a hidden short flag.
+    ///
+    /// This is more efficient, and easier than creating multiple hidden subcommands as one only
+    /// needs to check for the existence of this command, and not all variants.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let m = Command::new("prog")
+    ///             .arg(Arg::new("test")
+    ///                     .short('t')
+    ///                     .short_aliases(&['e', 's'])
+    ///                     .action(ArgAction::SetTrue)
+    ///                     .help("the file to add")
+    ///                     .required(false))
+    ///             .get_matches_from(vec![
+    ///                 "prog", "-s"
+    ///             ]);
+    /// assert_eq!(*m.get_one::<bool>("test").expect("defaulted by clap"), true);
+    /// ```
+    #[must_use]
+    pub fn short_aliases(mut self, names: &[char]) -> Self {
+        for s in names {
+            assert!(s != &'-', "short alias name cannot be `-`");
+            self.short_aliases.push((*s, false));
+        }
+        self
+    }
+
+    /// Add an alias, which functions as a visible long flag.
+    ///
+    /// Like [`Arg::alias`], except that they are visible inside the help message.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///             .arg(Arg::new("test")
+    ///                 .visible_alias("something-awesome")
+    ///                 .long("test")
+    ///                 .takes_value(true))
+    ///        .get_matches_from(vec![
+    ///             "prog", "--something-awesome", "coffee"
+    ///         ]);
+    /// assert!(m.contains_id("test"));
+    /// assert_eq!(m.value_of("test"), Some("coffee"));
+    /// ```
+    /// [`Command::alias`]: Arg::alias()
+    #[must_use]
+    pub fn visible_alias<S: Into<&'help str>>(mut self, name: S) -> Self {
+        self.aliases.push((name.into(), true));
+        self
+    }
+
+    /// Add an alias, which functions as a visible short flag.
+    ///
+    /// Like [`Arg::short_alias`], except that they are visible inside the help message.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///             .arg(Arg::new("test")
+    ///                 .long("test")
+    ///                 .visible_short_alias('t')
+    ///                 .takes_value(true))
+    ///        .get_matches_from(vec![
+    ///             "prog", "-t", "coffee"
+    ///         ]);
+    /// assert!(m.contains_id("test"));
+    /// assert_eq!(m.value_of("test"), Some("coffee"));
+    /// ```
+    #[must_use]
+    pub fn visible_short_alias(mut self, name: char) -> Self {
+        assert!(name != '-', "short alias name cannot be `-`");
+
+        self.short_aliases.push((name, true));
+        self
+    }
+
+    /// Add aliases, which function as visible long flags.
+    ///
+    /// Like [`Arg::aliases`], except that they are visible inside the help message.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let m = Command::new("prog")
+    ///             .arg(Arg::new("test")
+    ///                 .long("test")
+    ///                 .action(ArgAction::SetTrue)
+    ///                 .visible_aliases(&["something", "awesome", "cool"]))
+    ///        .get_matches_from(vec![
+    ///             "prog", "--awesome"
+    ///         ]);
+    /// assert_eq!(*m.get_one::<bool>("test").expect("defaulted by clap"), true);
+    /// ```
+    /// [`Command::aliases`]: Arg::aliases()
+    #[must_use]
+    pub fn visible_aliases(mut self, names: &[&'help str]) -> Self {
+        self.aliases.extend(names.iter().map(|n| (*n, true)));
+        self
+    }
+
+    /// Add aliases, which function as visible short flags.
+    ///
+    /// Like [`Arg::short_aliases`], except that they are visible inside the help message.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let m = Command::new("prog")
+    ///             .arg(Arg::new("test")
+    ///                 .long("test")
+    ///                 .action(ArgAction::SetTrue)
+    ///                 .visible_short_aliases(&['t', 'e']))
+    ///        .get_matches_from(vec![
+    ///             "prog", "-t"
+    ///         ]);
+    /// assert_eq!(*m.get_one::<bool>("test").expect("defaulted by clap"), true);
+    /// ```
+    #[must_use]
+    pub fn visible_short_aliases(mut self, names: &[char]) -> Self {
+        for n in names {
+            assert!(n != &'-', "short alias name cannot be `-`");
+            self.short_aliases.push((*n, true));
+        }
+        self
+    }
+
+    /// Specifies the index of a positional argument **starting at** 1.
+    ///
+    /// **NOTE:** The index refers to position according to **other positional argument**. It does
+    /// not define position in the argument list as a whole.
+    ///
+    /// **NOTE:** You can optionally leave off the `index` method, and the index will be
+    /// assigned in order of evaluation. Utilizing the `index` method allows for setting
+    /// indexes out of order
+    ///
+    /// **NOTE:** This is only meant to be used for positional arguments and shouldn't to be used
+    /// with [`Arg::short`] or [`Arg::long`].
+    ///
+    /// **NOTE:** When utilized with [`Arg::multiple_values(true)`], only the **last** positional argument
+    /// may be defined as multiple (i.e. with the highest index)
+    ///
+    /// # Panics
+    ///
+    /// [`Command`] will [`panic!`] if indexes are skipped (such as defining `index(1)` and `index(3)`
+    /// but not `index(2)`, or a positional argument is defined as multiple and is not the highest
+    /// index
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("config")
+    ///     .index(1)
+    /// # ;
+    /// ```
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("mode")
+    ///         .index(1))
+    ///     .arg(Arg::new("debug")
+    ///         .long("debug"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--debug", "fast"
+    ///     ]);
+    ///
+    /// assert!(m.contains_id("mode"));
+    /// assert_eq!(m.value_of("mode"), Some("fast")); // notice index(1) means "first positional"
+    ///                                               // *not* first argument
+    /// ```
+    /// [`Arg::short`]: Arg::short()
+    /// [`Arg::long`]: Arg::long()
+    /// [`Arg::multiple_values(true)`]: Arg::multiple_values()
+    /// [`panic!`]: https://doc.rust-lang.org/std/macro.panic!.html
+    /// [`Command`]: crate::Command
+    #[inline]
+    #[must_use]
+    pub fn index(mut self, idx: usize) -> Self {
+        self.index = Some(idx);
+        self
+    }
+
+    /// This arg is the last, or final, positional argument (i.e. has the highest
+    /// index) and is *only* able to be accessed via the `--` syntax (i.e. `$ prog args --
+    /// last_arg`).
+    ///
+    /// Even, if no other arguments are left to parse, if the user omits the `--` syntax
+    /// they will receive an [`UnknownArgument`] error. Setting an argument to `.last(true)` also
+    /// allows one to access this arg early using the `--` syntax. Accessing an arg early, even with
+    /// the `--` syntax is otherwise not possible.
+    ///
+    /// **NOTE:** This will change the usage string to look like `$ prog [OPTIONS] [-- <ARG>]` if
+    /// `ARG` is marked as `.last(true)`.
+    ///
+    /// **NOTE:** This setting will imply [`crate::Command::dont_collapse_args_in_usage`] because failing
+    /// to set this can make the usage string very confusing.
+    ///
+    /// **NOTE**: This setting only applies to positional arguments, and has no effect on OPTIONS
+    ///
+    /// **NOTE:** Setting this requires [`Arg::takes_value`]
+    ///
+    /// **CAUTION:** Using this setting *and* having child subcommands is not
+    /// recommended with the exception of *also* using
+    /// [`crate::Command::args_conflicts_with_subcommands`]
+    /// (or [`crate::Command::subcommand_negates_reqs`] if the argument marked `Last` is also
+    /// marked [`Arg::required`])
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("args")
+    ///     .takes_value(true)
+    ///     .last(true)
+    /// # ;
+    /// ```
+    ///
+    /// Setting `last` ensures the arg has the highest [index] of all positional args
+    /// and requires that the `--` syntax be used to access it early.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("first"))
+    ///     .arg(Arg::new("second"))
+    ///     .arg(Arg::new("third")
+    ///         .takes_value(true)
+    ///         .last(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "one", "--", "three"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok());
+    /// let m = res.unwrap();
+    /// assert_eq!(m.value_of("third"), Some("three"));
+    /// assert!(m.value_of("second").is_none());
+    /// ```
+    ///
+    /// Even if the positional argument marked `Last` is the only argument left to parse,
+    /// failing to use the `--` syntax results in an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("first"))
+    ///     .arg(Arg::new("second"))
+    ///     .arg(Arg::new("third")
+    ///         .takes_value(true)
+    ///         .last(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "one", "two", "three"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::UnknownArgument);
+    /// ```
+    /// [index]: Arg::index()
+    /// [`UnknownArgument`]: crate::ErrorKind::UnknownArgument
+    #[inline]
+    #[must_use]
+    pub fn last(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::Last)
+        } else {
+            self.unset_setting(ArgSettings::Last)
+        }
+    }
+
+    /// Specifies that the argument must be present.
+    ///
+    /// Required by default means it is required, when no other conflicting rules or overrides have
+    /// been evaluated. Conflicting rules take precedence over being required.
+    ///
+    /// **Pro tip:** Flags (i.e. not positional, or arguments that take values) shouldn't be
+    /// required by default. This is because if a flag were to be required, it should simply be
+    /// implied. No additional information is required from user. Flags by their very nature are
+    /// simply boolean on/off switches. The only time a user *should* be required to use a flag
+    /// is if the operation is destructive in nature, and the user is essentially proving to you,
+    /// "Yes, I know what I'm doing."
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .required(true)
+    /// # ;
+    /// ```
+    ///
+    /// Setting required requires that the argument be used at runtime.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required(true)
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--config", "file.conf",
+    ///     ]);
+    ///
+    /// assert!(res.is_ok());
+    /// ```
+    ///
+    /// Setting required and then *not* supplying that argument at runtime is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required(true)
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn required(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::Required)
+        } else {
+            self.unset_setting(ArgSettings::Required)
+        }
+    }
+
+    /// Sets an argument that is required when this one is present
+    ///
+    /// i.e. when using this argument, the following argument *must* be present.
+    ///
+    /// **NOTE:** [Conflicting] rules and [override] rules take precedence over being required
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .requires("input")
+    /// # ;
+    /// ```
+    ///
+    /// Setting [`Arg::requires(name)`] requires that the argument be used at runtime if the
+    /// defining argument is used. If the defining argument isn't used, the other argument isn't
+    /// required
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .requires("input")
+    ///         .long("config"))
+    ///     .arg(Arg::new("input"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok()); // We didn't use cfg, so input wasn't required
+    /// ```
+    ///
+    /// Setting [`Arg::requires(name)`] and *not* supplying that argument is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .requires("input")
+    ///         .long("config"))
+    ///     .arg(Arg::new("input"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--config", "file.conf"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [`Arg::requires(name)`]: Arg::requires()
+    /// [Conflicting]: Arg::conflicts_with()
+    /// [override]: Arg::overrides_with()
+    #[must_use]
+    pub fn requires<T: Key>(mut self, arg_id: T) -> Self {
+        self.requires.push((ArgPredicate::IsPresent, arg_id.into()));
+        self
+    }
+
+    /// This argument must be passed alone; it conflicts with all other arguments.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .exclusive(true)
+    /// # ;
+    /// ```
+    ///
+    /// Setting an exclusive argument and having any other arguments present at runtime
+    /// is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("exclusive")
+    ///         .takes_value(true)
+    ///         .exclusive(true)
+    ///         .long("exclusive"))
+    ///     .arg(Arg::new("debug")
+    ///         .long("debug"))
+    ///     .arg(Arg::new("input"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--exclusive", "file.conf", "file.txt"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::ArgumentConflict);
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn exclusive(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::Exclusive)
+        } else {
+            self.unset_setting(ArgSettings::Exclusive)
+        }
+    }
+
+    /// Specifies that an argument can be matched to all child [`Subcommand`]s.
+    ///
+    /// **NOTE:** Global arguments *only* propagate down, **not** up (to parent commands), however
+    /// their values once a user uses them will be propagated back up to parents. In effect, this
+    /// means one should *define* all global arguments at the top level, however it doesn't matter
+    /// where the user *uses* the global argument.
+    ///
+    /// # Examples
+    ///
+    /// Assume an application with two subcommands, and you'd like to define a
+    /// `--verbose` flag that can be called on any of the subcommands and parent, but you don't
+    /// want to clutter the source with three duplicate [`Arg`] definitions.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("verb")
+    ///         .long("verbose")
+    ///         .short('v')
+    ///         .action(ArgAction::SetTrue)
+    ///         .global(true))
+    ///     .subcommand(Command::new("test"))
+    ///     .subcommand(Command::new("do-stuff"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "do-stuff", "--verbose"
+    ///     ]);
+    ///
+    /// assert_eq!(m.subcommand_name(), Some("do-stuff"));
+    /// let sub_m = m.subcommand_matches("do-stuff").unwrap();
+    /// assert_eq!(*sub_m.get_one::<bool>("verb").expect("defaulted by clap"), true);
+    /// ```
+    ///
+    /// [`Subcommand`]: crate::Subcommand
+    #[inline]
+    #[must_use]
+    pub fn global(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::Global)
+        } else {
+            self.unset_setting(ArgSettings::Global)
+        }
+    }
+
+    /// Deprecated, replaced with [`Arg::action`] ([Issue #3772](https://github.com/clap-rs/clap/issues/3772))
+    #[inline]
+    #[must_use]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `Arg::action` (Issue #3772)")
+    )]
+    pub fn multiple_occurrences(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::MultipleOccurrences)
+        } else {
+            self.unset_setting(ArgSettings::MultipleOccurrences)
+        }
+    }
+
+    /// Deprecated, for flags this is replaced with `action(ArgAction::Count).value_parser(value_parser!(u8).range(..max))`
+    #[inline]
+    #[must_use]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "For flags, replaced with `action(ArgAction::Count).value_parser(value_parser!(u8).range(..max))`"
+        )
+    )]
+    pub fn max_occurrences(mut self, qty: usize) -> Self {
+        self.max_occurs = Some(qty);
+        if qty > 1 {
+            self.multiple_occurrences(true)
+        } else {
+            self
+        }
+    }
+
+    /// Check if the [`ArgSettings`] variant is currently set on the argument.
+    ///
+    /// [`ArgSettings`]: crate::ArgSettings
+    #[inline]
+    pub fn is_set(&self, s: ArgSettings) -> bool {
+        self.settings.is_set(s)
+    }
+
+    /// Apply a setting to the argument.
+    ///
+    /// See [`ArgSettings`] for a full list of possibilities and examples.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Arg, ArgSettings};
+    /// Arg::new("config")
+    ///     .setting(ArgSettings::Required)
+    ///     .setting(ArgSettings::TakesValue)
+    /// # ;
+    /// ```
+    ///
+    /// ```no_run
+    /// # use clap::{Arg, ArgSettings};
+    /// Arg::new("config")
+    ///     .setting(ArgSettings::Required | ArgSettings::TakesValue)
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn setting<F>(mut self, setting: F) -> Self
+    where
+        F: Into<ArgFlags>,
+    {
+        self.settings.insert(setting.into());
+        self
+    }
+
+    /// Remove a setting from the argument.
+    ///
+    /// See [`ArgSettings`] for a full list of possibilities and examples.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Arg, ArgSettings};
+    /// Arg::new("config")
+    ///     .unset_setting(ArgSettings::Required)
+    ///     .unset_setting(ArgSettings::TakesValue)
+    /// # ;
+    /// ```
+    ///
+    /// ```no_run
+    /// # use clap::{Arg, ArgSettings};
+    /// Arg::new("config")
+    ///     .unset_setting(ArgSettings::Required | ArgSettings::TakesValue)
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn unset_setting<F>(mut self, setting: F) -> Self
+    where
+        F: Into<ArgFlags>,
+    {
+        self.settings.remove(setting.into());
+        self
+    }
+}
+
+/// # Value Handling
+impl<'help> Arg<'help> {
+    /// Specifies that the argument takes a value at run time.
+    ///
+    /// **NOTE:** values for arguments may be specified in any of the following methods
+    ///
+    /// - Using a space such as `-o value` or `--option value`
+    /// - Using an equals and no space such as `-o=value` or `--option=value`
+    /// - Use a short and no space such as `-ovalue`
+    ///
+    /// **NOTE:** By default, args which allow [multiple values] are delimited by commas, meaning
+    /// `--option=val1,val2,val3` is three values for the `--option` argument. If you wish to
+    /// change the delimiter to another character you can use [`Arg::value_delimiter(char)`],
+    /// alternatively you can turn delimiting values **OFF** by using
+    /// [`Arg::use_value_delimiter(false)`][Arg::use_value_delimiter]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("mode")
+    ///         .long("mode")
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--mode", "fast"
+    ///     ]);
+    ///
+    /// assert!(m.contains_id("mode"));
+    /// assert_eq!(m.value_of("mode"), Some("fast"));
+    /// ```
+    /// [`Arg::value_delimiter(char)`]: Arg::value_delimiter()
+    /// [multiple values]: Arg::multiple_values
+    #[inline]
+    #[must_use]
+    pub fn takes_value(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::TakesValue)
+        } else {
+            self.unset_setting(ArgSettings::TakesValue)
+        }
+    }
+
+    /// Specify the behavior when parsing an argument
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .arg(
+    ///         Arg::new("flag")
+    ///             .long("flag")
+    ///             .action(clap::ArgAction::Set)
+    ///     );
+    ///
+    /// let matches = cmd.try_get_matches_from(["mycmd", "--flag", "value"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(matches.occurrences_of("flag"), 0);
+    /// assert_eq!(
+    ///     matches.get_many::<String>("flag").unwrap_or_default().map(|v| v.as_str()).collect::<Vec<_>>(),
+    ///     vec!["value"]
+    /// );
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn action(mut self, action: ArgAction) -> Self {
+        self.action = Some(action);
+        self
+    }
+
+    /// Specify the type of the argument.
+    ///
+    /// This allows parsing and validating a value before storing it into
+    /// [`ArgMatches`][crate::ArgMatches].
+    ///
+    /// See also
+    /// - [`value_parser!`][crate::value_parser!] for auto-selecting a value parser for a given type
+    ///   - [`BoolishValueParser`][crate::builder::BoolishValueParser], and [`FalseyValueParser`][crate::builder::FalseyValueParser] for alternative `bool` implementations
+    ///   - [`NonEmptyStringValueParser`][crate::builder::NonEmptyStringValueParser] for basic validation for strings
+    /// - [`RangedI64ValueParser`][crate::builder::RangedI64ValueParser] and [`RangedU64ValueParser`][crate::builder::RangedU64ValueParser] for numeric ranges
+    /// - [`EnumValueParser`][crate::builder::EnumValueParser] and  [`PossibleValuesParser`][crate::builder::PossibleValuesParser] for static enumerated values
+    /// - or any other [`TypedValueParser`][crate::builder::TypedValueParser] implementation
+    ///
+    /// ```rust
+    /// let mut cmd = clap::Command::new("raw")
+    ///     .arg(
+    ///         clap::Arg::new("color")
+    ///             .long("color")
+    ///             .value_parser(["always", "auto", "never"])
+    ///             .default_value("auto")
+    ///     )
+    ///     .arg(
+    ///         clap::Arg::new("hostname")
+    ///             .long("hostname")
+    ///             .value_parser(clap::builder::NonEmptyStringValueParser::new())
+    ///             .takes_value(true)
+    ///             .required(true)
+    ///     )
+    ///     .arg(
+    ///         clap::Arg::new("port")
+    ///             .long("port")
+    ///             .value_parser(clap::value_parser!(u16).range(3000..))
+    ///             .takes_value(true)
+    ///             .required(true)
+    ///     );
+    ///
+    /// let m = cmd.try_get_matches_from_mut(
+    ///     ["cmd", "--hostname", "rust-lang.org", "--port", "3001"]
+    /// ).unwrap();
+    ///
+    /// let color: &String = m.get_one("color")
+    ///     .expect("default");
+    /// assert_eq!(color, "auto");
+    ///
+    /// let hostname: &String = m.get_one("hostname")
+    ///     .expect("required");
+    /// assert_eq!(hostname, "rust-lang.org");
+    ///
+    /// let port: u16 = *m.get_one("port")
+    ///     .expect("required");
+    /// assert_eq!(port, 3001);
+    /// ```
+    pub fn value_parser(mut self, parser: impl Into<super::ValueParser>) -> Self {
+        self.value_parser = Some(parser.into());
+        self
+    }
+
+    /// Specifies that the argument may have an unknown number of values
+    ///
+    /// Without any other settings, this argument may appear only *once*.
+    ///
+    /// For example, `--opt val1 val2` is allowed, but `--opt val1 val2 --opt val3` is not.
+    ///
+    /// **NOTE:** Setting this requires [`Arg::takes_value`].
+    ///
+    /// **WARNING:**
+    ///
+    /// Setting `multiple_values` for an argument that takes a value, but with no other details can
+    /// be dangerous in some circumstances. Because multiple values are allowed,
+    /// `--option val1 val2 val3` is perfectly valid. Be careful when designing a CLI where
+    /// positional arguments are *also* expected as `clap` will continue parsing *values* until one
+    /// of the following happens:
+    ///
+    /// - It reaches the [maximum number of values]
+    /// - It reaches a [specific number of values]
+    /// - It finds another flag or option (i.e. something that starts with a `-`)
+    /// - It reaches a [value terminator][Arg::value_terminator] is reached
+    ///
+    /// Alternatively, [require a delimiter between values][Arg::require_delimiter].
+    ///
+    /// **WARNING:**
+    ///
+    /// When using args with `multiple_values` and [`subcommands`], one needs to consider the
+    /// possibility of an argument value being the same as a valid subcommand. By default `clap` will
+    /// parse the argument in question as a value *only if* a value is possible at that moment.
+    /// Otherwise it will be parsed as a subcommand. In effect, this means using `multiple_values` with no
+    /// additional parameters and a value that coincides with a subcommand name, the subcommand
+    /// cannot be called unless another argument is passed between them.
+    ///
+    /// As an example, consider a CLI with an option `--ui-paths=<paths>...` and subcommand `signer`
+    ///
+    /// The following would be parsed as values to `--ui-paths`.
+    ///
+    /// ```text
+    /// $ program --ui-paths path1 path2 signer
+    /// ```
+    ///
+    /// This is because `--ui-paths` accepts multiple values. `clap` will continue parsing values
+    /// until another argument is reached and it knows `--ui-paths` is done parsing.
+    ///
+    /// By adding additional parameters to `--ui-paths` we can solve this issue. Consider adding
+    /// [`Arg::number_of_values(1)`] or using *only* [`ArgAction::Append`]. The following are all
+    /// valid, and `signer` is parsed as a subcommand in the first case, but a value in the second
+    /// case.
+    ///
+    /// ```text
+    /// $ program --ui-paths path1 signer
+    /// $ program --ui-paths path1 --ui-paths signer signer
+    /// ```
+    ///
+    /// # Examples
+    ///
+    /// An example with options
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .multiple_values(true)
+    ///         .short('F'))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-F", "file1", "file2", "file3"
+    ///     ]);
+    ///
+    /// assert!(m.contains_id("file"));
+    /// let files: Vec<_> = m.values_of("file").unwrap().collect();
+    /// assert_eq!(files, ["file1", "file2", "file3"]);
+    /// ```
+    ///
+    /// Although `multiple_values` has been specified, we cannot use the argument more than once.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .multiple_values(true)
+    ///         .short('F'))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "-F", "file1", "-F", "file2", "-F", "file3"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::UnexpectedMultipleUsage)
+    /// ```
+    ///
+    /// A common mistake is to define an option which allows multiple values, and a positional
+    /// argument.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .multiple_values(true)
+    ///         .short('F'))
+    ///     .arg(Arg::new("word"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-F", "file1", "file2", "file3", "word"
+    ///     ]);
+    ///
+    /// assert!(m.contains_id("file"));
+    /// let files: Vec<_> = m.values_of("file").unwrap().collect();
+    /// assert_eq!(files, ["file1", "file2", "file3", "word"]); // wait...what?!
+    /// assert!(!m.contains_id("word")); // but we clearly used word!
+    /// ```
+    ///
+    /// The problem is `clap` doesn't know when to stop parsing values for "files". This is further
+    /// compounded by if we'd said `word -F file1 file2` it would have worked fine, so it would
+    /// appear to only fail sometimes...not good!
+    ///
+    /// A solution for the example above is to limit how many values with a [maximum], or [specific]
+    /// number, or to say [`ArgAction::Append`] is ok, but multiple values is not.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .action(ArgAction::Append)
+    ///         .short('F'))
+    ///     .arg(Arg::new("word"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-F", "file1", "-F", "file2", "-F", "file3", "word"
+    ///     ]);
+    ///
+    /// assert!(m.contains_id("file"));
+    /// let files: Vec<_> = m.values_of("file").unwrap().collect();
+    /// assert_eq!(files, ["file1", "file2", "file3"]);
+    /// assert!(m.contains_id("word"));
+    /// assert_eq!(m.value_of("word"), Some("word"));
+    /// ```
+    ///
+    /// As a final example, let's fix the above error and get a pretty message to the user :)
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind, ArgAction};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .action(ArgAction::Append)
+    ///         .short('F'))
+    ///     .arg(Arg::new("word"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "-F", "file1", "file2", "file3", "word"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::UnknownArgument);
+    /// ```
+    ///
+    /// [`subcommands`]: crate::Command::subcommand()
+    /// [`Arg::number_of_values(1)`]: Arg::number_of_values()
+    /// [maximum number of values]: Arg::max_values()
+    /// [specific number of values]: Arg::number_of_values()
+    /// [maximum]: Arg::max_values()
+    /// [specific]: Arg::number_of_values()
+    #[inline]
+    #[must_use]
+    pub fn multiple_values(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::MultipleValues)
+        } else {
+            self.unset_setting(ArgSettings::MultipleValues)
+        }
+    }
+
+    /// The number of values allowed for this argument.
+    ///
+    /// For example, if you had a
+    /// `-f <file>` argument where you wanted exactly 3 'files' you would set
+    /// `.number_of_values(3)`, and this argument wouldn't be satisfied unless the user provided
+    /// 3 and only 3 values.
+    ///
+    /// **NOTE:** Does *not* require [`Arg::multiple_occurrences(true)`] to be set. Setting
+    /// [`Arg::multiple_occurrences(true)`] would allow `-f <file> <file> <file> -f <file> <file> <file>` where
+    /// as *not* setting it would only allow one occurrence of this argument.
+    ///
+    /// **NOTE:** implicitly sets [`Arg::takes_value(true)`] and [`Arg::multiple_values(true)`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("file")
+    ///     .short('f')
+    ///     .number_of_values(3);
+    /// ```
+    ///
+    /// Not supplying the correct number of values is an error
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .number_of_values(2)
+    ///         .short('F'))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "-F", "file1"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::WrongNumberOfValues);
+    /// ```
+    /// [`Arg::multiple_occurrences(true)`]: Arg::multiple_occurrences()
+    #[inline]
+    #[must_use]
+    pub fn number_of_values(mut self, qty: usize) -> Self {
+        self.num_vals = Some(qty);
+        self.takes_value(true).multiple_values(true)
+    }
+
+    /// The *maximum* number of values are for this argument.
+    ///
+    /// For example, if you had a
+    /// `-f <file>` argument where you wanted up to 3 'files' you would set `.max_values(3)`, and
+    /// this argument would be satisfied if the user provided, 1, 2, or 3 values.
+    ///
+    /// **NOTE:** This does *not* implicitly set [`Arg::multiple_occurrences(true)`]. This is because
+    /// `-o val -o val` is multiple occurrences but a single value and `-o val1 val2` is a single
+    /// occurrence with multiple values. For positional arguments this **does** set
+    /// [`Arg::multiple_occurrences(true)`] because there is no way to determine the difference between multiple
+    /// occurrences and multiple values.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("file")
+    ///     .short('f')
+    ///     .max_values(3);
+    /// ```
+    ///
+    /// Supplying less than the maximum number of values is allowed
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .max_values(3)
+    ///         .short('F'))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "-F", "file1", "file2"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok());
+    /// let m = res.unwrap();
+    /// let files: Vec<_> = m.values_of("file").unwrap().collect();
+    /// assert_eq!(files, ["file1", "file2"]);
+    /// ```
+    ///
+    /// Supplying more than the maximum number of values is an error
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .max_values(2)
+    ///         .short('F'))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "-F", "file1", "file2", "file3"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::UnknownArgument);
+    /// ```
+    /// [`Arg::multiple_occurrences(true)`]: Arg::multiple_occurrences()
+    #[inline]
+    #[must_use]
+    pub fn max_values(mut self, qty: usize) -> Self {
+        self.max_vals = Some(qty);
+        self.takes_value(true).multiple_values(true)
+    }
+
+    /// The *minimum* number of values for this argument.
+    ///
+    /// For example, if you had a
+    /// `-f <file>` argument where you wanted at least 2 'files' you would set
+    /// `.min_values(2)`, and this argument would be satisfied if the user provided, 2 or more
+    /// values.
+    ///
+    /// **NOTE:** This does not implicitly set [`Arg::multiple_occurrences(true)`]. This is because
+    /// `-o val -o val` is multiple occurrences but a single value and `-o val1 val2` is a single
+    /// occurrence with multiple values. For positional arguments this **does** set
+    /// [`Arg::multiple_occurrences(true)`] because there is no way to determine the difference between multiple
+    /// occurrences and multiple values.
+    ///
+    /// **NOTE:** Passing a non-zero value is not the same as specifying [`Arg::required(true)`].
+    /// This is due to min and max validation only being performed for present arguments,
+    /// marking them as required will thus perform validation and a min value of 1
+    /// is unnecessary, ignored if not required.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("file")
+    ///     .short('f')
+    ///     .min_values(3);
+    /// ```
+    ///
+    /// Supplying more than the minimum number of values is allowed
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .min_values(2)
+    ///         .short('F'))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "-F", "file1", "file2", "file3"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok());
+    /// let m = res.unwrap();
+    /// let files: Vec<_> = m.values_of("file").unwrap().collect();
+    /// assert_eq!(files, ["file1", "file2", "file3"]);
+    /// ```
+    ///
+    /// Supplying less than the minimum number of values is an error
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("file")
+    ///         .takes_value(true)
+    ///         .min_values(2)
+    ///         .short('F'))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "-F", "file1"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::TooFewValues);
+    /// ```
+    /// [`Arg::multiple_occurrences(true)`]: Arg::multiple_occurrences()
+    /// [`Arg::required(true)`]: Arg::required()
+    #[inline]
+    #[must_use]
+    pub fn min_values(mut self, qty: usize) -> Self {
+        self.min_vals = Some(qty);
+        self.takes_value(true).multiple_values(true)
+    }
+
+    /// Placeholder for the argument's value in the help message / usage.
+    ///
+    /// This name is cosmetic only; the name is **not** used to access arguments.
+    /// This setting can be very helpful when describing the type of input the user should be
+    /// using, such as `FILE`, `INTERFACE`, etc. Although not required, it's somewhat convention to
+    /// use all capital letters for the value name.
+    ///
+    /// **NOTE:** implicitly sets [`Arg::takes_value(true)`]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("cfg")
+    ///     .long("config")
+    ///     .value_name("FILE")
+    /// # ;
+    /// ```
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("config")
+    ///         .long("config")
+    ///         .value_name("FILE")
+    ///         .help("Some help text"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--help"
+    ///     ]);
+    /// ```
+    /// Running the above program produces the following output
+    ///
+    /// ```text
+    /// valnames
+    ///
+    /// USAGE:
+    ///    valnames [OPTIONS]
+    ///
+    /// OPTIONS:
+    ///     --config <FILE>     Some help text
+    ///     -h, --help          Print help information
+    ///     -V, --version       Print version information
+    /// ```
+    /// [option]: Arg::takes_value()
+    /// [positional]: Arg::index()
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    #[inline]
+    #[must_use]
+    pub fn value_name(self, name: &'help str) -> Self {
+        self.value_names(&[name])
+    }
+
+    /// Placeholders for the argument's values in the help message / usage.
+    ///
+    /// These names are cosmetic only, used for help and usage strings only. The names are **not**
+    /// used to access arguments. The values of the arguments are accessed in numeric order (i.e.
+    /// if you specify two names `one` and `two` `one` will be the first matched value, `two` will
+    /// be the second).
+    ///
+    /// This setting can be very helpful when describing the type of input the user should be
+    /// using, such as `FILE`, `INTERFACE`, etc. Although not required, it's somewhat convention to
+    /// use all capital letters for the value name.
+    ///
+    /// **Pro Tip:** It may help to use [`Arg::next_line_help(true)`] if there are long, or
+    /// multiple value names in order to not throw off the help text alignment of all options.
+    ///
+    /// **NOTE:** implicitly sets [`Arg::takes_value(true)`] and [`Arg::multiple_values(true)`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("speed")
+    ///     .short('s')
+    ///     .value_names(&["fast", "slow"]);
+    /// ```
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("io")
+    ///         .long("io-files")
+    ///         .value_names(&["INFILE", "OUTFILE"]))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--help"
+    ///     ]);
+    /// ```
+    ///
+    /// Running the above program produces the following output
+    ///
+    /// ```text
+    /// valnames
+    ///
+    /// USAGE:
+    ///    valnames [OPTIONS]
+    ///
+    /// OPTIONS:
+    ///     -h, --help                       Print help information
+    ///     --io-files <INFILE> <OUTFILE>    Some help text
+    ///     -V, --version                    Print version information
+    /// ```
+    /// [`Arg::next_line_help(true)`]: Arg::next_line_help()
+    /// [`Arg::number_of_values`]: Arg::number_of_values()
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    /// [`Arg::multiple_values(true)`]: Arg::multiple_values()
+    #[must_use]
+    pub fn value_names(mut self, names: &[&'help str]) -> Self {
+        self.val_names = names.to_vec();
+        self.takes_value(true)
+    }
+
+    /// Provide the shell a hint about how to complete this argument.
+    ///
+    /// See [`ValueHint`][crate::ValueHint] for more information.
+    ///
+    /// **NOTE:** implicitly sets [`Arg::takes_value(true)`].
+    ///
+    /// For example, to take a username as argument:
+    ///
+    /// ```
+    /// # use clap::{Arg, ValueHint};
+    /// Arg::new("user")
+    ///     .short('u')
+    ///     .long("user")
+    ///     .value_hint(ValueHint::Username);
+    /// ```
+    ///
+    /// To take a full command line and its arguments (for example, when writing a command wrapper):
+    ///
+    /// ```
+    /// # use clap::{Command, Arg, ValueHint};
+    /// Command::new("prog")
+    ///     .trailing_var_arg(true)
+    ///     .arg(
+    ///         Arg::new("command")
+    ///             .takes_value(true)
+    ///             .multiple_values(true)
+    ///             .value_hint(ValueHint::CommandWithArguments)
+    ///     );
+    /// ```
+    #[must_use]
+    pub fn value_hint(mut self, value_hint: ValueHint) -> Self {
+        self.value_hint = Some(value_hint);
+        self.takes_value(true)
+    }
+
+    /// Deprecated, replaced with [`Arg::value_parser(...)`]
+    #[inline]
+    #[must_use]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `Arg::value_parser(...)`")
+    )]
+    pub fn validator<F, O, E>(mut self, mut f: F) -> Self
+    where
+        F: FnMut(&str) -> Result<O, E> + Send + 'help,
+        E: Into<Box<dyn Error + Send + Sync + 'static>>,
+    {
+        self.validator = Some(Arc::new(Mutex::new(move |s: &str| {
+            f(s).map(|_| ()).map_err(|e| e.into())
+        })));
+        self
+    }
+
+    /// Deprecated, replaced with [`Arg::value_parser(...)`]
+    #[must_use]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `Arg::value_parser(...)`")
+    )]
+    pub fn validator_os<F, O, E>(mut self, mut f: F) -> Self
+    where
+        F: FnMut(&OsStr) -> Result<O, E> + Send + 'help,
+        E: Into<Box<dyn Error + Send + Sync + 'static>>,
+    {
+        self.validator_os = Some(Arc::new(Mutex::new(move |s: &OsStr| {
+            f(s).map(|_| ()).map_err(|e| e.into())
+        })));
+        self
+    }
+
+    /// Deprecated in [Issue #3743](https://github.com/clap-rs/clap/issues/3743), replaced with [`Arg::value_parser(...)`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Deprecated in Issue #3743; eplaced with `Arg::value_parser(...)`"
+        )
+    )]
+    #[cfg(feature = "regex")]
+    #[must_use]
+    pub fn validator_regex(
+        self,
+        regex: impl Into<RegexRef<'help>>,
+        err_message: &'help str,
+    ) -> Self {
+        let regex = regex.into();
+        self.validator(move |s: &str| {
+            if regex.is_match(s) {
+                Ok(())
+            } else {
+                Err(err_message)
+            }
+        })
+    }
+
+    /// Deprecated, replaced with [`Arg::value_parser(PossibleValuesParser::new(...))`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Replaced with `Arg::value_parser(PossibleValuesParser::new(...)).takes_value(true)`"
+        )
+    )]
+    #[must_use]
+    pub fn possible_value<T>(mut self, value: T) -> Self
+    where
+        T: Into<PossibleValue<'help>>,
+    {
+        self.possible_vals.push(value.into());
+        self.takes_value(true)
+    }
+
+    /// Deprecated, replaced with [`Arg::value_parser(PossibleValuesParser::new(...))`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Replaced with `Arg::value_parser(PossibleValuesParser::new(...)).takes_value(true)`"
+        )
+    )]
+    #[must_use]
+    pub fn possible_values<I, T>(mut self, values: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<PossibleValue<'help>>,
+    {
+        self.possible_vals
+            .extend(values.into_iter().map(|value| value.into()));
+        self.takes_value(true)
+    }
+
+    /// Match values against [`Arg::possible_values`] without matching case.
+    ///
+    /// When other arguments are conditionally required based on the
+    /// value of a case-insensitive argument, the equality check done
+    /// by [`Arg::required_if_eq`], [`Arg::required_if_eq_any`], or
+    /// [`Arg::required_if_eq_all`] is case-insensitive.
+    ///
+    ///
+    /// **NOTE:** Setting this requires [`Arg::takes_value`]
+    ///
+    /// **NOTE:** To do unicode case folding, enable the `unicode` feature flag.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("pv")
+    ///     .arg(Arg::new("option")
+    ///         .long("option")
+    ///         .takes_value(true)
+    ///         .ignore_case(true)
+    ///         .value_parser(["test123"]))
+    ///     .get_matches_from(vec![
+    ///         "pv", "--option", "TeSt123",
+    ///     ]);
+    ///
+    /// assert!(m.value_of("option").unwrap().eq_ignore_ascii_case("test123"));
+    /// ```
+    ///
+    /// This setting also works when multiple values can be defined:
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("pv")
+    ///     .arg(Arg::new("option")
+    ///         .short('o')
+    ///         .long("option")
+    ///         .takes_value(true)
+    ///         .ignore_case(true)
+    ///         .multiple_values(true)
+    ///         .value_parser(["test123", "test321"]))
+    ///     .get_matches_from(vec![
+    ///         "pv", "--option", "TeSt123", "teST123", "tESt321"
+    ///     ]);
+    ///
+    /// let matched_vals = m.values_of("option").unwrap().collect::<Vec<_>>();
+    /// assert_eq!(&*matched_vals, &["TeSt123", "teST123", "tESt321"]);
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn ignore_case(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::IgnoreCase)
+        } else {
+            self.unset_setting(ArgSettings::IgnoreCase)
+        }
+    }
+
+    /// Allows values which start with a leading hyphen (`-`)
+    ///
+    /// **NOTE:** Setting this requires [`Arg::takes_value`]
+    ///
+    /// **WARNING**: Take caution when using this setting combined with
+    /// [`Arg::multiple_values`], as this becomes ambiguous `$ prog --arg -- -- val`. All
+    /// three `--, --, val` will be values when the user may have thought the second `--` would
+    /// constitute the normal, "Only positional args follow" idiom. To fix this, consider using
+    /// [`Arg::multiple_occurrences`] which only allows a single value at a time.
+    ///
+    /// **WARNING**: When building your CLIs, consider the effects of allowing leading hyphens and
+    /// the user passing in a value that matches a valid short. For example, `prog -opt -F` where
+    /// `-F` is supposed to be a value, yet `-F` is *also* a valid short for another arg.
+    /// Care should be taken when designing these args. This is compounded by the ability to "stack"
+    /// short args. I.e. if `-val` is supposed to be a value, but `-v`, `-a`, and `-l` are all valid
+    /// shorts.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("pat")
+    ///         .takes_value(true)
+    ///         .allow_hyphen_values(true)
+    ///         .long("pattern"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--pattern", "-file"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("pat"), Some("-file"));
+    /// ```
+    ///
+    /// Not setting `Arg::allow_hyphen_values(true)` and supplying a value which starts with a
+    /// hyphen is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("pat")
+    ///         .takes_value(true)
+    ///         .long("pattern"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--pattern", "-file"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::UnknownArgument);
+    /// ```
+    /// [`Arg::number_of_values(1)`]: Arg::number_of_values()
+    #[inline]
+    #[must_use]
+    pub fn allow_hyphen_values(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::AllowHyphenValues)
+        } else {
+            self.unset_setting(ArgSettings::AllowHyphenValues)
+        }
+    }
+
+    /// Deprecated, replaced with [`Arg::value_parser(...)`] with either [`ValueParser::os_string()`][crate::builder::ValueParser::os_string]
+    /// or [`ValueParser::path_buf()`][crate::builder::ValueParser::path_buf]
+    #[inline]
+    #[must_use]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Replaced with `Arg::value_parser(...)` with either `ValueParser::os_string()` or `ValueParser::path_buf()`"
+        )
+    )]
+    pub fn allow_invalid_utf8(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::AllowInvalidUtf8)
+        } else {
+            self.unset_setting(ArgSettings::AllowInvalidUtf8)
+        }
+    }
+
+    /// Deprecated, replaced with [`Arg::value_parser(NonEmptyStringValueParser::new())`]
+    #[inline]
+    #[must_use]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Replaced with `Arg::value_parser(NonEmptyStringValueParser::new())`"
+        )
+    )]
+    pub fn forbid_empty_values(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::ForbidEmptyValues)
+        } else {
+            self.unset_setting(ArgSettings::ForbidEmptyValues)
+        }
+    }
+
+    /// Requires that options use the `--option=val` syntax
+    ///
+    /// i.e. an equals between the option and associated value.
+    ///
+    /// **NOTE:** Setting this requires [`Arg::takes_value`]
+    ///
+    /// # Examples
+    ///
+    /// Setting `require_equals` requires that the option have an equals sign between
+    /// it and the associated value.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .require_equals(true)
+    ///         .long("config"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--config=file.conf"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok());
+    /// ```
+    ///
+    /// Setting `require_equals` and *not* supplying the equals will cause an
+    /// error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .require_equals(true)
+    ///         .long("config"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--config", "file.conf"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::NoEquals);
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn require_equals(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::RequireEquals)
+        } else {
+            self.unset_setting(ArgSettings::RequireEquals)
+        }
+    }
+
+    /// Specifies that an argument should allow grouping of multiple values via a
+    /// delimiter.
+    ///
+    /// i.e. should `--option=val1,val2,val3` be parsed as three values (`val1`, `val2`,
+    /// and `val3`) or as a single value (`val1,val2,val3`). Defaults to using `,` (comma) as the
+    /// value delimiter for all arguments that accept values (options and positional arguments)
+    ///
+    /// **NOTE:** When this setting is used, it will default [`Arg::value_delimiter`]
+    /// to the comma `,`.
+    ///
+    /// **NOTE:** Implicitly sets [`Arg::takes_value`]
+    ///
+    /// # Examples
+    ///
+    /// The following example shows the default behavior.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let delims = Command::new("prog")
+    ///     .arg(Arg::new("option")
+    ///         .long("option")
+    ///         .use_value_delimiter(true)
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--option=val1,val2,val3",
+    ///     ]);
+    ///
+    /// assert!(delims.contains_id("option"));
+    /// assert_eq!(delims.values_of("option").unwrap().collect::<Vec<_>>(), ["val1", "val2", "val3"]);
+    /// ```
+    /// The next example shows the difference when turning delimiters off. This is the default
+    /// behavior
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let nodelims = Command::new("prog")
+    ///     .arg(Arg::new("option")
+    ///         .long("option")
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--option=val1,val2,val3",
+    ///     ]);
+    ///
+    /// assert!(nodelims.contains_id("option"));
+    /// assert_eq!(nodelims.value_of("option").unwrap(), "val1,val2,val3");
+    /// ```
+    /// [`Arg::value_delimiter`]: Arg::value_delimiter()
+    #[inline]
+    #[must_use]
+    pub fn use_value_delimiter(mut self, yes: bool) -> Self {
+        if yes {
+            if self.val_delim.is_none() {
+                self.val_delim = Some(',');
+            }
+            self.takes_value(true)
+                .setting(ArgSettings::UseValueDelimiter)
+        } else {
+            self.val_delim = None;
+            self.unset_setting(ArgSettings::UseValueDelimiter)
+        }
+    }
+
+    /// Deprecated, replaced with [`Arg::use_value_delimiter`]
+    #[inline]
+    #[must_use]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Arg::use_value_delimiter`")
+    )]
+    pub fn use_delimiter(self, yes: bool) -> Self {
+        self.use_value_delimiter(yes)
+    }
+
+    /// Separator between the arguments values, defaults to `,` (comma).
+    ///
+    /// **NOTE:** implicitly sets [`Arg::use_value_delimiter(true)`]
+    ///
+    /// **NOTE:** implicitly sets [`Arg::takes_value(true)`]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("config")
+    ///         .short('c')
+    ///         .long("config")
+    ///         .value_delimiter(';'))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--config=val1;val2;val3"
+    ///     ]);
+    ///
+    /// assert_eq!(m.values_of("config").unwrap().collect::<Vec<_>>(), ["val1", "val2", "val3"])
+    /// ```
+    /// [`Arg::use_value_delimiter(true)`]: Arg::use_value_delimiter()
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    #[inline]
+    #[must_use]
+    pub fn value_delimiter(mut self, d: char) -> Self {
+        self.val_delim = Some(d);
+        self.takes_value(true).use_value_delimiter(true)
+    }
+
+    /// Specifies that *multiple values* may only be set using the delimiter.
+    ///
+    /// This means if an option is encountered, and no delimiter is found, it is assumed that no
+    /// additional values for that option follow. This is unlike the default, where it is generally
+    /// assumed that more values will follow regardless of whether or not a delimiter is used.
+    ///
+    /// **NOTE:** The default is `false`.
+    ///
+    /// **NOTE:** Setting this requires [`Arg::use_value_delimiter`] and
+    /// [`Arg::takes_value`]
+    ///
+    /// **NOTE:** It's a good idea to inform the user that use of a delimiter is required, either
+    /// through help text or other means.
+    ///
+    /// # Examples
+    ///
+    /// These examples demonstrate what happens when `require_delimiter(true)` is used. Notice
+    /// everything works in this first example, as we use a delimiter, as expected.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let delims = Command::new("prog")
+    ///     .arg(Arg::new("opt")
+    ///         .short('o')
+    ///         .takes_value(true)
+    ///         .use_value_delimiter(true)
+    ///         .require_delimiter(true)
+    ///         .multiple_values(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-o", "val1,val2,val3",
+    ///     ]);
+    ///
+    /// assert!(delims.contains_id("opt"));
+    /// assert_eq!(delims.values_of("opt").unwrap().collect::<Vec<_>>(), ["val1", "val2", "val3"]);
+    /// ```
+    ///
+    /// In this next example, we will *not* use a delimiter. Notice it's now an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("opt")
+    ///         .short('o')
+    ///         .takes_value(true)
+    ///         .use_value_delimiter(true)
+    ///         .require_delimiter(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "-o", "val1", "val2", "val3",
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// let err = res.unwrap_err();
+    /// assert_eq!(err.kind(), ErrorKind::UnknownArgument);
+    /// ```
+    ///
+    /// What's happening is `-o` is getting `val1`, and because delimiters are required yet none
+    /// were present, it stops parsing `-o`. At this point it reaches `val2` and because no
+    /// positional arguments have been defined, it's an error of an unexpected argument.
+    ///
+    /// In this final example, we contrast the above with `clap`'s default behavior where the above
+    /// is *not* an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let delims = Command::new("prog")
+    ///     .arg(Arg::new("opt")
+    ///         .short('o')
+    ///         .takes_value(true)
+    ///         .multiple_values(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-o", "val1", "val2", "val3",
+    ///     ]);
+    ///
+    /// assert!(delims.contains_id("opt"));
+    /// assert_eq!(delims.values_of("opt").unwrap().collect::<Vec<_>>(), ["val1", "val2", "val3"]);
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn require_value_delimiter(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::RequireDelimiter)
+        } else {
+            self.unset_setting(ArgSettings::RequireDelimiter)
+        }
+    }
+
+    /// Deprecated, replaced with [`Arg::require_value_delimiter`]
+    #[inline]
+    #[must_use]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Arg::require_value_delimiter`")
+    )]
+    pub fn require_delimiter(self, yes: bool) -> Self {
+        self.require_value_delimiter(yes)
+    }
+
+    /// Sentinel to **stop** parsing multiple values of a give argument.
+    ///
+    /// By default when
+    /// one sets [`multiple_values(true)`] on an argument, clap will continue parsing values for that
+    /// argument until it reaches another valid argument, or one of the other more specific settings
+    /// for multiple values is used (such as [`min_values`], [`max_values`] or
+    /// [`number_of_values`]).
+    ///
+    /// **NOTE:** This setting only applies to [options] and [positional arguments]
+    ///
+    /// **NOTE:** When the terminator is passed in on the command line, it is **not** stored as one
+    /// of the values
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("vals")
+    ///     .takes_value(true)
+    ///     .multiple_values(true)
+    ///     .value_terminator(";")
+    /// # ;
+    /// ```
+    ///
+    /// The following example uses two arguments, a sequence of commands, and the location in which
+    /// to perform them
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("cmds")
+    ///         .takes_value(true)
+    ///         .multiple_values(true)
+    ///         .allow_hyphen_values(true)
+    ///         .value_terminator(";"))
+    ///     .arg(Arg::new("location"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "find", "-type", "f", "-name", "special", ";", "/home/clap"
+    ///     ]);
+    /// let cmds: Vec<_> = m.values_of("cmds").unwrap().collect();
+    /// assert_eq!(&cmds, &["find", "-type", "f", "-name", "special"]);
+    /// assert_eq!(m.value_of("location"), Some("/home/clap"));
+    /// ```
+    /// [options]: Arg::takes_value()
+    /// [positional arguments]: Arg::index()
+    /// [`multiple_values(true)`]: Arg::multiple_values()
+    /// [`min_values`]: Arg::min_values()
+    /// [`number_of_values`]: Arg::number_of_values()
+    /// [`max_values`]: Arg::max_values()
+    #[inline]
+    #[must_use]
+    pub fn value_terminator(mut self, term: &'help str) -> Self {
+        self.terminator = Some(term);
+        self.takes_value(true)
+    }
+
+    /// Consume all following arguments.
+    ///
+    /// Do not be parse them individually, but rather pass them in entirety.
+    ///
+    /// It is worth noting that setting this requires all values to come after a `--` to indicate
+    /// they should all be captured. For example:
+    ///
+    /// ```text
+    /// --foo something -- -v -v -v -b -b -b --baz -q -u -x
+    /// ```
+    ///
+    /// Will result in everything after `--` to be considered one raw argument. This behavior
+    /// may not be exactly what you are expecting and using [`crate::Command::trailing_var_arg`]
+    /// may be more appropriate.
+    ///
+    /// **NOTE:** Implicitly sets [`Arg::takes_value(true)`] [`Arg::multiple_values(true)`],
+    /// [`Arg::allow_hyphen_values(true)`], and [`Arg::last(true)`] when set to `true`.
+    ///
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    /// [`Arg::multiple_values(true)`]: Arg::multiple_values()
+    /// [`Arg::allow_hyphen_values(true)`]: Arg::allow_hyphen_values()
+    /// [`Arg::last(true)`]: Arg::last()
+    #[inline]
+    #[must_use]
+    pub fn raw(self, yes: bool) -> Self {
+        self.takes_value(yes)
+            .multiple_values(yes)
+            .allow_hyphen_values(yes)
+            .last(yes)
+    }
+
+    /// Value for the argument when not present.
+    ///
+    /// **NOTE:** If the user *does not* use this argument at runtime, [`ArgMatches::occurrences_of`]
+    /// will return `0` even though the [`ArgMatches::value_of`] will return the default specified.
+    ///
+    /// **NOTE:** If the user *does not* use this argument at runtime [`ArgMatches::contains_id`] will
+    /// still return `true`. If you wish to determine whether the argument was used at runtime or
+    /// not, consider [`ArgMatches::value_source`][crate::ArgMatches::value_source].
+    ///
+    /// **NOTE:** This setting is perfectly compatible with [`Arg::default_value_if`] but slightly
+    /// different. `Arg::default_value` *only* takes effect when the user has not provided this arg
+    /// at runtime. `Arg::default_value_if` however only takes effect when the user has not provided
+    /// a value at runtime **and** these other conditions are met as well. If you have set
+    /// `Arg::default_value` and `Arg::default_value_if`, and the user **did not** provide this arg
+    /// at runtime, nor were the conditions met for `Arg::default_value_if`, the `Arg::default_value`
+    /// will be applied.
+    ///
+    /// **NOTE:** This implicitly sets [`Arg::takes_value(true)`].
+    ///
+    /// # Examples
+    ///
+    /// First we use the default value without providing any value at runtime.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ValueSource};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("opt")
+    ///         .long("myopt")
+    ///         .default_value("myval"))
+    ///     .get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("opt"), Some("myval"));
+    /// assert!(m.contains_id("opt"));
+    /// assert_eq!(m.value_source("opt"), Some(ValueSource::DefaultValue));
+    /// ```
+    ///
+    /// Next we provide a value at runtime to override the default.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ValueSource};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("opt")
+    ///         .long("myopt")
+    ///         .default_value("myval"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--myopt=non_default"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("opt"), Some("non_default"));
+    /// assert!(m.contains_id("opt"));
+    /// assert_eq!(m.value_source("opt"), Some(ValueSource::CommandLine));
+    /// ```
+    /// [`ArgMatches::occurrences_of`]: crate::ArgMatches::occurrences_of()
+    /// [`ArgMatches::value_of`]: crate::ArgMatches::value_of()
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    /// [`ArgMatches::contains_id`]: crate::ArgMatches::contains_id()
+    /// [`Arg::default_value_if`]: Arg::default_value_if()
+    #[inline]
+    #[must_use]
+    pub fn default_value(self, val: &'help str) -> Self {
+        self.default_values_os(&[OsStr::new(val)])
+    }
+
+    /// Value for the argument when not present.
+    ///
+    /// See [`Arg::default_value`].
+    ///
+    /// [`Arg::default_value`]: Arg::default_value()
+    /// [`OsStr`]: std::ffi::OsStr
+    #[inline]
+    #[must_use]
+    pub fn default_value_os(self, val: &'help OsStr) -> Self {
+        self.default_values_os(&[val])
+    }
+
+    /// Value for the argument when not present.
+    ///
+    /// See [`Arg::default_value`].
+    ///
+    /// [`Arg::default_value`]: Arg::default_value()
+    #[inline]
+    #[must_use]
+    pub fn default_values(self, vals: &[&'help str]) -> Self {
+        let vals_vec: Vec<_> = vals.iter().map(|val| OsStr::new(*val)).collect();
+        self.default_values_os(&vals_vec[..])
+    }
+
+    /// Value for the argument when not present.
+    ///
+    /// See [`Arg::default_values`].
+    ///
+    /// [`Arg::default_values`]: Arg::default_values()
+    /// [`OsStr`]: std::ffi::OsStr
+    #[inline]
+    #[must_use]
+    pub fn default_values_os(mut self, vals: &[&'help OsStr]) -> Self {
+        self.default_vals = vals.to_vec();
+        self.takes_value(true)
+    }
+
+    /// Value for the argument when the flag is present but no value is specified.
+    ///
+    /// This configuration option is often used to give the user a shortcut and allow them to
+    /// efficiently specify an option argument without requiring an explicitly value. The `--color`
+    /// argument is a common example. By, supplying an default, such as `default_missing_value("always")`,
+    /// the user can quickly just add `--color` to the command line to produce the desired color output.
+    ///
+    /// **NOTE:** using this configuration option requires the use of the `.min_values(0)` and the
+    /// `.require_equals(true)` configuration option. These are required in order to unambiguously
+    /// determine what, if any, value was supplied for the argument.
+    ///
+    /// # Examples
+    ///
+    /// For POSIX style `--color`:
+    /// ```rust
+    /// # use clap::{Command, Arg, ValueSource};
+    /// fn cli() -> Command<'static> {
+    ///     Command::new("prog")
+    ///         .arg(Arg::new("color").long("color")
+    ///             .value_name("WHEN")
+    ///             .value_parser(["always", "auto", "never"])
+    ///             .default_value("auto")
+    ///             .min_values(0)
+    ///             .require_equals(true)
+    ///             .default_missing_value("always")
+    ///             .help("Specify WHEN to colorize output.")
+    ///         )
+    /// }
+    ///
+    /// // first, we'll provide no arguments
+    /// let m  = cli().get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    /// assert_eq!(m.value_of("color"), Some("auto"));
+    /// assert_eq!(m.value_source("color"), Some(ValueSource::DefaultValue));
+    ///
+    /// // next, we'll provide a runtime value to override the default (as usually done).
+    /// let m  = cli().get_matches_from(vec![
+    ///         "prog", "--color=never"
+    ///     ]);
+    /// assert_eq!(m.value_of("color"), Some("never"));
+    /// assert_eq!(m.value_source("color"), Some(ValueSource::CommandLine));
+    ///
+    /// // finally, we will use the shortcut and only provide the argument without a value.
+    /// let m  = cli().get_matches_from(vec![
+    ///         "prog", "--color"
+    ///     ]);
+    /// assert_eq!(m.value_of("color"), Some("always"));
+    /// assert_eq!(m.value_source("color"), Some(ValueSource::CommandLine));
+    /// ```
+    ///
+    /// For bool literals:
+    /// ```rust
+    /// # use clap::{Command, Arg, ValueSource, value_parser};
+    /// fn cli() -> Command<'static> {
+    ///     Command::new("prog")
+    ///         .arg(Arg::new("create").long("create")
+    ///             .value_name("BOOL")
+    ///             .value_parser(value_parser!(bool))
+    ///             .min_values(0)
+    ///             .require_equals(true)
+    ///             .default_missing_value("true")
+    ///         )
+    /// }
+    ///
+    /// // first, we'll provide no arguments
+    /// let m  = cli().get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    /// assert_eq!(m.get_one::<bool>("create").copied(), None);
+    ///
+    /// // next, we'll provide a runtime value to override the default (as usually done).
+    /// let m  = cli().get_matches_from(vec![
+    ///         "prog", "--create=false"
+    ///     ]);
+    /// assert_eq!(m.get_one::<bool>("create").copied(), Some(false));
+    /// assert_eq!(m.value_source("create"), Some(ValueSource::CommandLine));
+    ///
+    /// // finally, we will use the shortcut and only provide the argument without a value.
+    /// let m  = cli().get_matches_from(vec![
+    ///         "prog", "--create"
+    ///     ]);
+    /// assert_eq!(m.get_one::<bool>("create").copied(), Some(true));
+    /// assert_eq!(m.value_source("create"), Some(ValueSource::CommandLine));
+    /// ```
+    ///
+    /// [`ArgMatches::value_of`]: ArgMatches::value_of()
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    /// [`Arg::default_value`]: Arg::default_value()
+    #[inline]
+    #[must_use]
+    pub fn default_missing_value(self, val: &'help str) -> Self {
+        self.default_missing_values_os(&[OsStr::new(val)])
+    }
+
+    /// Value for the argument when the flag is present but no value is specified.
+    ///
+    /// See [`Arg::default_missing_value`].
+    ///
+    /// [`Arg::default_missing_value`]: Arg::default_missing_value()
+    /// [`OsStr`]: std::ffi::OsStr
+    #[inline]
+    #[must_use]
+    pub fn default_missing_value_os(self, val: &'help OsStr) -> Self {
+        self.default_missing_values_os(&[val])
+    }
+
+    /// Value for the argument when the flag is present but no value is specified.
+    ///
+    /// See [`Arg::default_missing_value`].
+    ///
+    /// [`Arg::default_missing_value`]: Arg::default_missing_value()
+    #[inline]
+    #[must_use]
+    pub fn default_missing_values(self, vals: &[&'help str]) -> Self {
+        let vals_vec: Vec<_> = vals.iter().map(|val| OsStr::new(*val)).collect();
+        self.default_missing_values_os(&vals_vec[..])
+    }
+
+    /// Value for the argument when the flag is present but no value is specified.
+    ///
+    /// See [`Arg::default_missing_values`].
+    ///
+    /// [`Arg::default_missing_values`]: Arg::default_missing_values()
+    /// [`OsStr`]: std::ffi::OsStr
+    #[inline]
+    #[must_use]
+    pub fn default_missing_values_os(mut self, vals: &[&'help OsStr]) -> Self {
+        self.default_missing_vals = vals.to_vec();
+        self.takes_value(true)
+    }
+
+    /// Read from `name` environment variable when argument is not present.
+    ///
+    /// If it is not present in the environment, then default
+    /// rules will apply.
+    ///
+    /// If user sets the argument in the environment:
+    /// - When [`Arg::takes_value(true)`] is not set, the flag is considered raised.
+    /// - When [`Arg::takes_value(true)`] is set, [`ArgMatches::value_of`] will
+    ///   return value of the environment variable.
+    ///
+    /// If user doesn't set the argument in the environment:
+    /// - When [`Arg::takes_value(true)`] is not set, the flag is considered off.
+    /// - When [`Arg::takes_value(true)`] is set, [`ArgMatches::value_of`] will
+    ///   return the default specified.
+    ///
+    /// # Examples
+    ///
+    /// In this example, we show the variable coming from the environment:
+    ///
+    /// ```rust
+    /// # use std::env;
+    /// # use clap::{Command, Arg};
+    ///
+    /// env::set_var("MY_FLAG", "env");
+    ///
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag")
+    ///         .env("MY_FLAG")
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("flag"), Some("env"));
+    /// ```
+    ///
+    /// In this example, because [`Arg::takes_value(false)`] (by default),
+    /// `prog` is a flag that accepts an optional, case-insensitive boolean literal.
+    /// A `false` literal is `n`, `no`, `f`, `false`, `off` or `0`.
+    /// An absent environment variable will also be considered as `false`.
+    /// Anything else will considered as `true`.
+    ///
+    /// ```rust
+    /// # use std::env;
+    /// # use clap::{Command, Arg};
+    ///
+    /// env::set_var("TRUE_FLAG", "true");
+    /// env::set_var("FALSE_FLAG", "0");
+    ///
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("true_flag")
+    ///         .long("true_flag")
+    ///         .env("TRUE_FLAG"))
+    ///     .arg(Arg::new("false_flag")
+    ///         .long("false_flag")
+    ///         .env("FALSE_FLAG"))
+    ///     .arg(Arg::new("absent_flag")
+    ///         .long("absent_flag")
+    ///         .env("ABSENT_FLAG"))
+    ///     .get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert!(m.is_present("true_flag"));
+    /// assert_eq!(m.value_of("true_flag"), None);
+    /// assert!(!m.is_present("false_flag"));
+    /// assert!(!m.is_present("absent_flag"));
+    /// ```
+    ///
+    /// In this example, we show the variable coming from an option on the CLI:
+    ///
+    /// ```rust
+    /// # use std::env;
+    /// # use clap::{Command, Arg};
+    ///
+    /// env::set_var("MY_FLAG", "env");
+    ///
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag")
+    ///         .env("MY_FLAG")
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--flag", "opt"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("flag"), Some("opt"));
+    /// ```
+    ///
+    /// In this example, we show the variable coming from the environment even with the
+    /// presence of a default:
+    ///
+    /// ```rust
+    /// # use std::env;
+    /// # use clap::{Command, Arg};
+    ///
+    /// env::set_var("MY_FLAG", "env");
+    ///
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag")
+    ///         .env("MY_FLAG")
+    ///         .takes_value(true)
+    ///         .default_value("default"))
+    ///     .get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("flag"), Some("env"));
+    /// ```
+    ///
+    /// In this example, we show the use of multiple values in a single environment variable:
+    ///
+    /// ```rust
+    /// # use std::env;
+    /// # use clap::{Command, Arg};
+    ///
+    /// env::set_var("MY_FLAG_MULTI", "env1,env2");
+    ///
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag")
+    ///         .env("MY_FLAG_MULTI")
+    ///         .takes_value(true)
+    ///         .multiple_values(true)
+    ///         .use_value_delimiter(true))
+    ///     .get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert_eq!(m.values_of("flag").unwrap().collect::<Vec<_>>(), vec!["env1", "env2"]);
+    /// ```
+    /// [`ArgMatches::value_of`]: crate::ArgMatches::value_of()
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    /// [`Arg::use_value_delimiter(true)`]: Arg::use_value_delimiter()
+    #[cfg(feature = "env")]
+    #[inline]
+    #[must_use]
+    pub fn env(self, name: &'help str) -> Self {
+        self.env_os(OsStr::new(name))
+    }
+
+    /// Read from `name` environment variable when argument is not present.
+    ///
+    /// See [`Arg::env`].
+    #[cfg(feature = "env")]
+    #[inline]
+    #[must_use]
+    pub fn env_os(mut self, name: &'help OsStr) -> Self {
+        self.env = Some((name, env::var_os(name)));
+        self
+    }
+}
+
+/// # Help
+impl<'help> Arg<'help> {
+    /// Sets the description of the argument for short help (`-h`).
+    ///
+    /// Typically, this is a short (one line) description of the arg.
+    ///
+    /// If [`Arg::long_help`] is not specified, this message will be displayed for `--help`.
+    ///
+    /// **NOTE:** Only `Arg::help` is used in completion script generation in order to be concise
+    ///
+    /// # Examples
+    ///
+    /// Any valid UTF-8 is allowed in the help text. The one exception is when one wishes to
+    /// include a newline in the help text and have the following text be properly aligned with all
+    /// the other help text.
+    ///
+    /// Setting `help` displays a short message to the side of the argument when the user passes
+    /// `-h` or `--help` (by default).
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .long("config")
+    ///         .help("Some help text describing the --config arg"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--help"
+    ///     ]);
+    /// ```
+    ///
+    /// The above example displays
+    ///
+    /// ```notrust
+    /// helptest
+    ///
+    /// USAGE:
+    ///    helptest [OPTIONS]
+    ///
+    /// OPTIONS:
+    ///     --config     Some help text describing the --config arg
+    /// -h, --help       Print help information
+    /// -V, --version    Print version information
+    /// ```
+    /// [`Arg::long_help`]: Arg::long_help()
+    #[inline]
+    #[must_use]
+    pub fn help(mut self, h: impl Into<Option<&'help str>>) -> Self {
+        self.help = h.into();
+        self
+    }
+
+    /// Sets the description of the argument for long help (`--help`).
+    ///
+    /// Typically this a more detailed (multi-line) message
+    /// that describes the arg.
+    ///
+    /// If [`Arg::help`] is not specified, this message will be displayed for `-h`.
+    ///
+    /// **NOTE:** Only [`Arg::help`] is used in completion script generation in order to be concise
+    ///
+    /// # Examples
+    ///
+    /// Any valid UTF-8 is allowed in the help text. The one exception is when one wishes to
+    /// include a newline in the help text and have the following text be properly aligned with all
+    /// the other help text.
+    ///
+    /// Setting `help` displays a short message to the side of the argument when the user passes
+    /// `-h` or `--help` (by default).
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .long("config")
+    ///         .long_help(
+    /// "The config file used by the myprog must be in JSON format
+    /// with only valid keys and may not contain other nonsense
+    /// that cannot be read by this program. Obviously I'm going on
+    /// and on, so I'll stop now."))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--help"
+    ///     ]);
+    /// ```
+    ///
+    /// The above example displays
+    ///
+    /// ```text
+    /// prog
+    ///
+    /// USAGE:
+    ///     prog [OPTIONS]
+    ///
+    /// OPTIONS:
+    ///         --config
+    ///             The config file used by the myprog must be in JSON format
+    ///             with only valid keys and may not contain other nonsense
+    ///             that cannot be read by this program. Obviously I'm going on
+    ///             and on, so I'll stop now.
+    ///
+    ///     -h, --help
+    ///             Print help information
+    ///
+    ///     -V, --version
+    ///             Print version information
+    /// ```
+    /// [`Arg::help`]: Arg::help()
+    #[inline]
+    #[must_use]
+    pub fn long_help(mut self, h: impl Into<Option<&'help str>>) -> Self {
+        self.long_help = h.into();
+        self
+    }
+
+    /// Allows custom ordering of args within the help message.
+    ///
+    /// Args with a lower value will be displayed first in the help message. This is helpful when
+    /// one would like to emphasise frequently used args, or prioritize those towards the top of
+    /// the list. Args with duplicate display orders will be displayed in alphabetical order.
+    ///
+    /// **NOTE:** The default is 999 for all arguments.
+    ///
+    /// **NOTE:** This setting is ignored for [positional arguments] which are always displayed in
+    /// [index] order.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("a") // Typically args are grouped alphabetically by name.
+    ///                              // Args without a display_order have a value of 999 and are
+    ///                              // displayed alphabetically with all other 999 valued args.
+    ///         .long("long-option")
+    ///         .short('o')
+    ///         .takes_value(true)
+    ///         .help("Some help and text"))
+    ///     .arg(Arg::new("b")
+    ///         .long("other-option")
+    ///         .short('O')
+    ///         .takes_value(true)
+    ///         .display_order(1)   // In order to force this arg to appear *first*
+    ///                             // all we have to do is give it a value lower than 999.
+    ///                             // Any other args with a value of 1 will be displayed
+    ///                             // alphabetically with this one...then 2 values, then 3, etc.
+    ///         .help("I should be first!"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--help"
+    ///     ]);
+    /// ```
+    ///
+    /// The above example displays the following help message
+    ///
+    /// ```text
+    /// cust-ord
+    ///
+    /// USAGE:
+    ///     cust-ord [OPTIONS]
+    ///
+    /// OPTIONS:
+    ///     -h, --help                Print help information
+    ///     -V, --version             Print version information
+    ///     -O, --other-option <b>    I should be first!
+    ///     -o, --long-option <a>     Some help and text
+    /// ```
+    /// [positional arguments]: Arg::index()
+    /// [index]: Arg::index()
+    #[inline]
+    #[must_use]
+    pub fn display_order(mut self, ord: usize) -> Self {
+        self.disp_ord.set_explicit(ord);
+        self
+    }
+
+    /// Override the [current] help section.
+    ///
+    /// [current]: crate::Command::help_heading
+    #[inline]
+    #[must_use]
+    pub fn help_heading<O>(mut self, heading: O) -> Self
+    where
+        O: Into<Option<&'help str>>,
+    {
+        self.help_heading = Some(heading.into());
+        self
+    }
+
+    /// Render the [help][Arg::help] on the line after the argument.
+    ///
+    /// This can be helpful for arguments with very long or complex help messages.
+    /// This can also be helpful for arguments with very long flag names, or many/long value names.
+    ///
+    /// **NOTE:** To apply this setting to all arguments and subcommands, consider using
+    /// [`crate::Command::next_line_help`]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("opt")
+    ///         .long("long-option-flag")
+    ///         .short('o')
+    ///         .takes_value(true)
+    ///         .next_line_help(true)
+    ///         .value_names(&["value1", "value2"])
+    ///         .help("Some really long help and complex\n\
+    ///                help that makes more sense to be\n\
+    ///                on a line after the option"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--help"
+    ///     ]);
+    /// ```
+    ///
+    /// The above example displays the following help message
+    ///
+    /// ```text
+    /// nlh
+    ///
+    /// USAGE:
+    ///     nlh [OPTIONS]
+    ///
+    /// OPTIONS:
+    ///     -h, --help       Print help information
+    ///     -V, --version    Print version information
+    ///     -o, --long-option-flag <value1> <value2>
+    ///         Some really long help and complex
+    ///         help that makes more sense to be
+    ///         on a line after the option
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn next_line_help(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::NextLineHelp)
+        } else {
+            self.unset_setting(ArgSettings::NextLineHelp)
+        }
+    }
+
+    /// Do not display the argument in help message.
+    ///
+    /// **NOTE:** This does **not** hide the argument from usage strings on error
+    ///
+    /// # Examples
+    ///
+    /// Setting `Hidden` will hide the argument when displaying help text
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .long("config")
+    ///         .hide(true)
+    ///         .help("Some help text describing the --config arg"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--help"
+    ///     ]);
+    /// ```
+    ///
+    /// The above example displays
+    ///
+    /// ```text
+    /// helptest
+    ///
+    /// USAGE:
+    ///    helptest [OPTIONS]
+    ///
+    /// OPTIONS:
+    /// -h, --help       Print help information
+    /// -V, --version    Print version information
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn hide(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::Hidden)
+        } else {
+            self.unset_setting(ArgSettings::Hidden)
+        }
+    }
+
+    /// Do not display the [possible values][crate::builder::ValueParser::possible_values] in the help message.
+    ///
+    /// This is useful for args with many values, or ones which are explained elsewhere in the
+    /// help text.
+    ///
+    /// **NOTE:** Setting this requires [`Arg::takes_value`]
+    ///
+    /// To set this for all arguments, see
+    /// [`Command::hide_possible_values`][crate::Command::hide_possible_values].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("mode")
+    ///         .long("mode")
+    ///         .value_parser(["fast", "slow"])
+    ///         .takes_value(true)
+    ///         .hide_possible_values(true));
+    /// ```
+    /// If we were to run the above program with `--help` the `[values: fast, slow]` portion of
+    /// the help text would be omitted.
+    #[inline]
+    #[must_use]
+    pub fn hide_possible_values(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::HidePossibleValues)
+        } else {
+            self.unset_setting(ArgSettings::HidePossibleValues)
+        }
+    }
+
+    /// Do not display the default value of the argument in the help message.
+    ///
+    /// This is useful when default behavior of an arg is explained elsewhere in the help text.
+    ///
+    /// **NOTE:** Setting this requires [`Arg::takes_value`]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("connect")
+    ///     .arg(Arg::new("host")
+    ///         .long("host")
+    ///         .default_value("localhost")
+    ///         .takes_value(true)
+    ///         .hide_default_value(true));
+    ///
+    /// ```
+    ///
+    /// If we were to run the above program with `--help` the `[default: localhost]` portion of
+    /// the help text would be omitted.
+    #[inline]
+    #[must_use]
+    pub fn hide_default_value(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::HideDefaultValue)
+        } else {
+            self.unset_setting(ArgSettings::HideDefaultValue)
+        }
+    }
+
+    /// Do not display in help the environment variable name.
+    ///
+    /// This is useful when the variable option is explained elsewhere in the help text.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("mode")
+    ///         .long("mode")
+    ///         .env("MODE")
+    ///         .takes_value(true)
+    ///         .hide_env(true));
+    /// ```
+    ///
+    /// If we were to run the above program with `--help` the `[env: MODE]` portion of the help
+    /// text would be omitted.
+    #[cfg(feature = "env")]
+    #[inline]
+    #[must_use]
+    pub fn hide_env(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::HideEnv)
+        } else {
+            self.unset_setting(ArgSettings::HideEnv)
+        }
+    }
+
+    /// Do not display in help any values inside the associated ENV variables for the argument.
+    ///
+    /// This is useful when ENV vars contain sensitive values.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("connect")
+    ///     .arg(Arg::new("host")
+    ///         .long("host")
+    ///         .env("CONNECT")
+    ///         .takes_value(true)
+    ///         .hide_env_values(true));
+    ///
+    /// ```
+    ///
+    /// If we were to run the above program with `$ CONNECT=super_secret connect --help` the
+    /// `[default: CONNECT=super_secret]` portion of the help text would be omitted.
+    #[cfg(feature = "env")]
+    #[inline]
+    #[must_use]
+    pub fn hide_env_values(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::HideEnvValues)
+        } else {
+            self.unset_setting(ArgSettings::HideEnvValues)
+        }
+    }
+
+    /// Hides an argument from short help (`-h`).
+    ///
+    /// **NOTE:** This does **not** hide the argument from usage strings on error
+    ///
+    /// **NOTE:** Setting this option will cause next-line-help output style to be used
+    /// when long help (`--help`) is called.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("debug")
+    ///     .hide_short_help(true);
+    /// ```
+    ///
+    /// Setting `hide_short_help(true)` will hide the argument when displaying short help text
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .long("config")
+    ///         .hide_short_help(true)
+    ///         .help("Some help text describing the --config arg"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-h"
+    ///     ]);
+    /// ```
+    ///
+    /// The above example displays
+    ///
+    /// ```text
+    /// helptest
+    ///
+    /// USAGE:
+    ///    helptest [OPTIONS]
+    ///
+    /// OPTIONS:
+    /// -h, --help       Print help information
+    /// -V, --version    Print version information
+    /// ```
+    ///
+    /// However, when --help is called
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .long("config")
+    ///         .hide_short_help(true)
+    ///         .help("Some help text describing the --config arg"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--help"
+    ///     ]);
+    /// ```
+    ///
+    /// Then the following would be displayed
+    ///
+    /// ```text
+    /// helptest
+    ///
+    /// USAGE:
+    ///    helptest [OPTIONS]
+    ///
+    /// OPTIONS:
+    ///     --config     Some help text describing the --config arg
+    /// -h, --help       Print help information
+    /// -V, --version    Print version information
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn hide_short_help(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::HiddenShortHelp)
+        } else {
+            self.unset_setting(ArgSettings::HiddenShortHelp)
+        }
+    }
+
+    /// Hides an argument from long help (`--help`).
+    ///
+    /// **NOTE:** This does **not** hide the argument from usage strings on error
+    ///
+    /// **NOTE:** Setting this option will cause next-line-help output style to be used
+    /// when long help (`--help`) is called.
+    ///
+    /// # Examples
+    ///
+    /// Setting `hide_long_help(true)` will hide the argument when displaying long help text
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .long("config")
+    ///         .hide_long_help(true)
+    ///         .help("Some help text describing the --config arg"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--help"
+    ///     ]);
+    /// ```
+    ///
+    /// The above example displays
+    ///
+    /// ```text
+    /// helptest
+    ///
+    /// USAGE:
+    ///    helptest [OPTIONS]
+    ///
+    /// OPTIONS:
+    /// -h, --help       Print help information
+    /// -V, --version    Print version information
+    /// ```
+    ///
+    /// However, when -h is called
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .long("config")
+    ///         .hide_long_help(true)
+    ///         .help("Some help text describing the --config arg"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-h"
+    ///     ]);
+    /// ```
+    ///
+    /// Then the following would be displayed
+    ///
+    /// ```text
+    /// helptest
+    ///
+    /// USAGE:
+    ///    helptest [OPTIONS]
+    ///
+    /// OPTIONS:
+    ///     --config     Some help text describing the --config arg
+    /// -h, --help       Print help information
+    /// -V, --version    Print version information
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn hide_long_help(self, yes: bool) -> Self {
+        if yes {
+            self.setting(ArgSettings::HiddenLongHelp)
+        } else {
+            self.unset_setting(ArgSettings::HiddenLongHelp)
+        }
+    }
+}
+
+/// # Advanced Argument Relations
+impl<'help> Arg<'help> {
+    /// The name of the [`ArgGroup`] the argument belongs to.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("debug")
+    ///     .long("debug")
+    ///     .group("mode")
+    /// # ;
+    /// ```
+    ///
+    /// Multiple arguments can be a member of a single group and then the group checked as if it
+    /// was one of said arguments.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("debug")
+    ///         .long("debug")
+    ///         .group("mode"))
+    ///     .arg(Arg::new("verbose")
+    ///         .long("verbose")
+    ///         .group("mode"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--debug"
+    ///     ]);
+    /// assert!(m.contains_id("mode"));
+    /// ```
+    ///
+    /// [`ArgGroup`]: crate::ArgGroup
+    #[must_use]
+    pub fn group<T: Key>(mut self, group_id: T) -> Self {
+        self.groups.push(group_id.into());
+        self
+    }
+
+    /// The names of [`ArgGroup`]'s the argument belongs to.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Arg::new("debug")
+    ///     .long("debug")
+    ///     .groups(&["mode", "verbosity"])
+    /// # ;
+    /// ```
+    ///
+    /// Arguments can be members of multiple groups and then the group checked as if it
+    /// was one of said arguments.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("debug")
+    ///         .long("debug")
+    ///         .groups(&["mode", "verbosity"]))
+    ///     .arg(Arg::new("verbose")
+    ///         .long("verbose")
+    ///         .groups(&["mode", "verbosity"]))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--debug"
+    ///     ]);
+    /// assert!(m.contains_id("mode"));
+    /// assert!(m.contains_id("verbosity"));
+    /// ```
+    ///
+    /// [`ArgGroup`]: crate::ArgGroup
+    #[must_use]
+    pub fn groups<T: Key>(mut self, group_ids: &[T]) -> Self {
+        self.groups.extend(group_ids.iter().map(Id::from));
+        self
+    }
+
+    /// Specifies the value of the argument if `arg` has been used at runtime.
+    ///
+    /// If `val` is set to `None`, `arg` only needs to be present. If `val` is set to `"some-val"`
+    /// then `arg` must be present at runtime **and** have the value `val`.
+    ///
+    /// If `default` is set to `None`, `default_value` will be removed.
+    ///
+    /// **NOTE:** This setting is perfectly compatible with [`Arg::default_value`] but slightly
+    /// different. `Arg::default_value` *only* takes effect when the user has not provided this arg
+    /// at runtime. This setting however only takes effect when the user has not provided a value at
+    /// runtime **and** these other conditions are met as well. If you have set `Arg::default_value`
+    /// and `Arg::default_value_if`, and the user **did not** provide this arg at runtime, nor were
+    /// the conditions met for `Arg::default_value_if`, the `Arg::default_value` will be applied.
+    ///
+    /// **NOTE:** This implicitly sets [`Arg::takes_value(true)`].
+    ///
+    /// # Examples
+    ///
+    /// First we use the default value only if another arg is present at runtime.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .default_value_if("flag", None, Some("default")))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--flag"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("other"), Some("default"));
+    /// ```
+    ///
+    /// Next we run the same test, but without providing `--flag`.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .default_value_if("flag", None, Some("default")))
+    ///     .get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("other"), None);
+    /// ```
+    ///
+    /// Now lets only use the default value if `--opt` contains the value `special`.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("opt")
+    ///         .takes_value(true)
+    ///         .long("opt"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .default_value_if("opt", Some("special"), Some("default")))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--opt", "special"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("other"), Some("default"));
+    /// ```
+    ///
+    /// We can run the same test and provide any value *other than* `special` and we won't get a
+    /// default value.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("opt")
+    ///         .takes_value(true)
+    ///         .long("opt"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .default_value_if("opt", Some("special"), Some("default")))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--opt", "hahaha"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("other"), None);
+    /// ```
+    ///
+    /// If we want to unset the default value for an Arg based on the presence or
+    /// value of some other Arg.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .default_value("default")
+    ///         .default_value_if("flag", None, None))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--flag"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("other"), None);
+    /// ```
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    /// [`Arg::default_value`]: Arg::default_value()
+    #[must_use]
+    pub fn default_value_if<T: Key>(
+        self,
+        arg_id: T,
+        val: Option<&'help str>,
+        default: Option<&'help str>,
+    ) -> Self {
+        self.default_value_if_os(arg_id, val.map(OsStr::new), default.map(OsStr::new))
+    }
+
+    /// Provides a conditional default value in the exact same manner as [`Arg::default_value_if`]
+    /// only using [`OsStr`]s instead.
+    ///
+    /// [`Arg::default_value_if`]: Arg::default_value_if()
+    /// [`OsStr`]: std::ffi::OsStr
+    #[must_use]
+    pub fn default_value_if_os<T: Key>(
+        mut self,
+        arg_id: T,
+        val: Option<&'help OsStr>,
+        default: Option<&'help OsStr>,
+    ) -> Self {
+        self.default_vals_ifs
+            .push((arg_id.into(), val.into(), default));
+        self.takes_value(true)
+    }
+
+    /// Specifies multiple values and conditions in the same manner as [`Arg::default_value_if`].
+    ///
+    /// The method takes a slice of tuples in the `(arg, Option<val>, default)` format.
+    ///
+    /// **NOTE**: The conditions are stored in order and evaluated in the same order. I.e. the first
+    /// if multiple conditions are true, the first one found will be applied and the ultimate value.
+    ///
+    /// # Examples
+    ///
+    /// First we use the default value only if another arg is present at runtime.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag"))
+    ///     .arg(Arg::new("opt")
+    ///         .long("opt")
+    ///         .takes_value(true))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .default_value_ifs(&[
+    ///             ("flag", None, Some("default")),
+    ///             ("opt", Some("channal"), Some("chan")),
+    ///         ]))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--opt", "channal"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("other"), Some("chan"));
+    /// ```
+    ///
+    /// Next we run the same test, but without providing `--flag`.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .default_value_ifs(&[
+    ///             ("flag", None, Some("default")),
+    ///             ("opt", Some("channal"), Some("chan")),
+    ///         ]))
+    ///     .get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("other"), None);
+    /// ```
+    ///
+    /// We can also see that these values are applied in order, and if more than one condition is
+    /// true, only the first evaluated "wins"
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .arg(Arg::new("flag")
+    ///         .long("flag"))
+    ///     .arg(Arg::new("opt")
+    ///         .long("opt")
+    ///         .takes_value(true))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .default_value_ifs(&[
+    ///             ("flag", None, Some("default")),
+    ///             ("opt", Some("channal"), Some("chan")),
+    ///         ]))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--opt", "channal", "--flag"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("other"), Some("default"));
+    /// ```
+    /// [`Arg::takes_value(true)`]: Arg::takes_value()
+    /// [`Arg::default_value_if`]: Arg::default_value_if()
+    #[must_use]
+    pub fn default_value_ifs<T: Key>(
+        mut self,
+        ifs: &[(T, Option<&'help str>, Option<&'help str>)],
+    ) -> Self {
+        for (arg, val, default) in ifs {
+            self = self.default_value_if_os(arg, val.map(OsStr::new), default.map(OsStr::new));
+        }
+        self
+    }
+
+    /// Provides multiple conditional default values in the exact same manner as
+    /// [`Arg::default_value_ifs`] only using [`OsStr`]s instead.
+    ///
+    /// [`Arg::default_value_ifs`]: Arg::default_value_ifs()
+    /// [`OsStr`]: std::ffi::OsStr
+    #[must_use]
+    pub fn default_value_ifs_os<T: Key>(
+        mut self,
+        ifs: &[(T, Option<&'help OsStr>, Option<&'help OsStr>)],
+    ) -> Self {
+        for (arg, val, default) in ifs {
+            self = self.default_value_if_os(arg, *val, *default);
+        }
+        self
+    }
+
+    /// Set this arg as [required] as long as the specified argument is not present at runtime.
+    ///
+    /// **Pro Tip:** Using `Arg::required_unless_present` implies [`Arg::required`] and is therefore not
+    /// mandatory to also set.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .required_unless_present("debug")
+    /// # ;
+    /// ```
+    ///
+    /// In the following example, the required argument is *not* provided,
+    /// but it's not an error because the `unless` arg has been supplied.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_unless_present("dbg")
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("dbg")
+    ///         .long("debug"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--debug"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok());
+    /// ```
+    ///
+    /// Setting `Arg::required_unless_present(name)` and *not* supplying `name` or this arg is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_unless_present("dbg")
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("dbg")
+    ///         .long("debug"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [required]: Arg::required()
+    #[must_use]
+    pub fn required_unless_present<T: Key>(mut self, arg_id: T) -> Self {
+        self.r_unless.push(arg_id.into());
+        self
+    }
+
+    /// Sets this arg as [required] unless *all* of the specified arguments are present at runtime.
+    ///
+    /// In other words, parsing will succeed only if user either
+    /// * supplies the `self` arg.
+    /// * supplies *all* of the `names` arguments.
+    ///
+    /// **NOTE:** If you wish for this argument to only be required unless *any of* these args are
+    /// present see [`Arg::required_unless_present_any`]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .required_unless_present_all(&["cfg", "dbg"])
+    /// # ;
+    /// ```
+    ///
+    /// In the following example, the required argument is *not* provided, but it's not an error
+    /// because *all* of the `names` args have been supplied.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_unless_present_all(&["dbg", "infile"])
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("dbg")
+    ///         .long("debug"))
+    ///     .arg(Arg::new("infile")
+    ///         .short('i')
+    ///         .takes_value(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--debug", "-i", "file"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok());
+    /// ```
+    ///
+    /// Setting [`Arg::required_unless_present_all(names)`] and *not* supplying
+    /// either *all* of `unless` args or the `self` arg is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_unless_present_all(&["dbg", "infile"])
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("dbg")
+    ///         .long("debug"))
+    ///     .arg(Arg::new("infile")
+    ///         .short('i')
+    ///         .takes_value(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [required]: Arg::required()
+    /// [`Arg::required_unless_present_any`]: Arg::required_unless_present_any()
+    /// [`Arg::required_unless_present_all(names)`]: Arg::required_unless_present_all()
+    #[must_use]
+    pub fn required_unless_present_all<T, I>(mut self, names: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Key,
+    {
+        self.r_unless_all.extend(names.into_iter().map(Id::from));
+        self
+    }
+
+    /// Sets this arg as [required] unless *any* of the specified arguments are present at runtime.
+    ///
+    /// In other words, parsing will succeed only if user either
+    /// * supplies the `self` arg.
+    /// * supplies *one or more* of the `unless` arguments.
+    ///
+    /// **NOTE:** If you wish for this argument to be required unless *all of* these args are
+    /// present see [`Arg::required_unless_present_all`]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .required_unless_present_any(&["cfg", "dbg"])
+    /// # ;
+    /// ```
+    ///
+    /// Setting [`Arg::required_unless_present_any(names)`] requires that the argument be used at runtime
+    /// *unless* *at least one of* the args in `names` are present. In the following example, the
+    /// required argument is *not* provided, but it's not an error because one the `unless` args
+    /// have been supplied.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_unless_present_any(&["dbg", "infile"])
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("dbg")
+    ///         .long("debug"))
+    ///     .arg(Arg::new("infile")
+    ///         .short('i')
+    ///         .takes_value(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--debug"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok());
+    /// ```
+    ///
+    /// Setting [`Arg::required_unless_present_any(names)`] and *not* supplying *at least one of* `names`
+    /// or this arg is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_unless_present_any(&["dbg", "infile"])
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("dbg")
+    ///         .long("debug"))
+    ///     .arg(Arg::new("infile")
+    ///         .short('i')
+    ///         .takes_value(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [required]: Arg::required()
+    /// [`Arg::required_unless_present_any(names)`]: Arg::required_unless_present_any()
+    /// [`Arg::required_unless_present_all`]: Arg::required_unless_present_all()
+    #[must_use]
+    pub fn required_unless_present_any<T, I>(mut self, names: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Key,
+    {
+        self.r_unless.extend(names.into_iter().map(Id::from));
+        self
+    }
+
+    /// This argument is [required] only if the specified `arg` is present at runtime and its value
+    /// equals `val`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .required_if_eq("other_arg", "value")
+    /// # ;
+    /// ```
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .required_if_eq("other", "special")
+    ///         .long("config"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .takes_value(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--other", "not-special"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok()); // We didn't use --other=special, so "cfg" wasn't required
+    ///
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .required_if_eq("other", "special")
+    ///         .long("config"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .takes_value(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--other", "special"
+    ///     ]);
+    ///
+    /// // We did use --other=special so "cfg" had become required but was missing.
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    ///
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .required_if_eq("other", "special")
+    ///         .long("config"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .takes_value(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--other", "SPECIAL"
+    ///     ]);
+    ///
+    /// // By default, the comparison is case-sensitive, so "cfg" wasn't required
+    /// assert!(res.is_ok());
+    ///
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .required_if_eq("other", "special")
+    ///         .long("config"))
+    ///     .arg(Arg::new("other")
+    ///         .long("other")
+    ///         .ignore_case(true)
+    ///         .takes_value(true))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--other", "SPECIAL"
+    ///     ]);
+    ///
+    /// // However, case-insensitive comparisons can be enabled.  This typically occurs when using Arg::possible_values().
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [`Arg::requires(name)`]: Arg::requires()
+    /// [Conflicting]: Arg::conflicts_with()
+    /// [required]: Arg::required()
+    #[must_use]
+    pub fn required_if_eq<T: Key>(mut self, arg_id: T, val: &'help str) -> Self {
+        self.r_ifs.push((arg_id.into(), val));
+        self
+    }
+
+    /// Specify this argument is [required] based on multiple conditions.
+    ///
+    /// The conditions are set up in a `(arg, val)` style tuple. The requirement will only become
+    /// valid if one of the specified `arg`'s value equals its corresponding `val`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .required_if_eq_any(&[
+    ///         ("extra", "val"),
+    ///         ("option", "spec")
+    ///     ])
+    /// # ;
+    /// ```
+    ///
+    /// Setting `Arg::required_if_eq_any(&[(arg, val)])` makes this arg required if any of the `arg`s
+    /// are used at runtime and it's corresponding value is equal to `val`. If the `arg`'s value is
+    /// anything other than `val`, this argument isn't required.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_if_eq_any(&[
+    ///             ("extra", "val"),
+    ///             ("option", "spec")
+    ///         ])
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("extra")
+    ///         .takes_value(true)
+    ///         .long("extra"))
+    ///     .arg(Arg::new("option")
+    ///         .takes_value(true)
+    ///         .long("option"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--option", "other"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok()); // We didn't use --option=spec, or --extra=val so "cfg" isn't required
+    /// ```
+    ///
+    /// Setting `Arg::required_if_eq_any(&[(arg, val)])` and having any of the `arg`s used with its
+    /// value of `val` but *not* using this arg is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_if_eq_any(&[
+    ///             ("extra", "val"),
+    ///             ("option", "spec")
+    ///         ])
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("extra")
+    ///         .takes_value(true)
+    ///         .long("extra"))
+    ///     .arg(Arg::new("option")
+    ///         .takes_value(true)
+    ///         .long("option"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--option", "spec"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [`Arg::requires(name)`]: Arg::requires()
+    /// [Conflicting]: Arg::conflicts_with()
+    /// [required]: Arg::required()
+    #[must_use]
+    pub fn required_if_eq_any<T: Key>(mut self, ifs: &[(T, &'help str)]) -> Self {
+        self.r_ifs
+            .extend(ifs.iter().map(|(id, val)| (Id::from_ref(id), *val)));
+        self
+    }
+
+    /// Specify this argument is [required] based on multiple conditions.
+    ///
+    /// The conditions are set up in a `(arg, val)` style tuple. The requirement will only become
+    /// valid if every one of the specified `arg`'s value equals its corresponding `val`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .required_if_eq_all(&[
+    ///         ("extra", "val"),
+    ///         ("option", "spec")
+    ///     ])
+    /// # ;
+    /// ```
+    ///
+    /// Setting `Arg::required_if_eq_all(&[(arg, val)])` makes this arg required if all of the `arg`s
+    /// are used at runtime and every value is equal to its corresponding `val`. If the `arg`'s value is
+    /// anything other than `val`, this argument isn't required.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_if_eq_all(&[
+    ///             ("extra", "val"),
+    ///             ("option", "spec")
+    ///         ])
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("extra")
+    ///         .takes_value(true)
+    ///         .long("extra"))
+    ///     .arg(Arg::new("option")
+    ///         .takes_value(true)
+    ///         .long("option"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--option", "spec"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok()); // We didn't use --option=spec --extra=val so "cfg" isn't required
+    /// ```
+    ///
+    /// Setting `Arg::required_if_eq_all(&[(arg, val)])` and having all of the `arg`s used with its
+    /// value of `val` but *not* using this arg is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .required_if_eq_all(&[
+    ///             ("extra", "val"),
+    ///             ("option", "spec")
+    ///         ])
+    ///         .takes_value(true)
+    ///         .long("config"))
+    ///     .arg(Arg::new("extra")
+    ///         .takes_value(true)
+    ///         .long("extra"))
+    ///     .arg(Arg::new("option")
+    ///         .takes_value(true)
+    ///         .long("option"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--extra", "val", "--option", "spec"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [required]: Arg::required()
+    #[must_use]
+    pub fn required_if_eq_all<T: Key>(mut self, ifs: &[(T, &'help str)]) -> Self {
+        self.r_ifs_all
+            .extend(ifs.iter().map(|(id, val)| (Id::from_ref(id), *val)));
+        self
+    }
+
+    /// Require another argument if this arg was present at runtime and its value equals to `val`.
+    ///
+    /// This method takes `value, another_arg` pair. At runtime, clap will check
+    /// if this arg (`self`) is present and its value equals to `val`.
+    /// If it does, `another_arg` will be marked as required.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .requires_if("val", "arg")
+    /// # ;
+    /// ```
+    ///
+    /// Setting `Arg::requires_if(val, arg)` requires that the `arg` be used at runtime if the
+    /// defining argument's value is equal to `val`. If the defining argument is anything other than
+    /// `val`, the other argument isn't required.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .requires_if("my.cfg", "other")
+    ///         .long("config"))
+    ///     .arg(Arg::new("other"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--config", "some.cfg"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok()); // We didn't use --config=my.cfg, so other wasn't required
+    /// ```
+    ///
+    /// Setting `Arg::requires_if(val, arg)` and setting the value to `val` but *not* supplying
+    /// `arg` is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .requires_if("my.cfg", "input")
+    ///         .long("config"))
+    ///     .arg(Arg::new("input"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--config", "my.cfg"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [`Arg::requires(name)`]: Arg::requires()
+    /// [Conflicting]: Arg::conflicts_with()
+    /// [override]: Arg::overrides_with()
+    #[must_use]
+    pub fn requires_if<T: Key>(mut self, val: &'help str, arg_id: T) -> Self {
+        self.requires
+            .push((ArgPredicate::Equals(OsStr::new(val)), arg_id.into()));
+        self
+    }
+
+    /// Allows multiple conditional requirements.
+    ///
+    /// The requirement will only become valid if this arg's value equals `val`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .requires_ifs(&[
+    ///         ("val", "arg"),
+    ///         ("other_val", "arg2"),
+    ///     ])
+    /// # ;
+    /// ```
+    ///
+    /// Setting `Arg::requires_ifs(&["val", "arg"])` requires that the `arg` be used at runtime if the
+    /// defining argument's value is equal to `val`. If the defining argument's value is anything other
+    /// than `val`, `arg` isn't required.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .requires_ifs(&[
+    ///             ("special.conf", "opt"),
+    ///             ("other.conf", "other"),
+    ///         ])
+    ///         .long("config"))
+    ///     .arg(Arg::new("opt")
+    ///         .long("option")
+    ///         .takes_value(true))
+    ///     .arg(Arg::new("other"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--config", "special.conf"
+    ///     ]);
+    ///
+    /// assert!(res.is_err()); // We  used --config=special.conf so --option <val> is required
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [`Arg::requires(name)`]: Arg::requires()
+    /// [Conflicting]: Arg::conflicts_with()
+    /// [override]: Arg::overrides_with()
+    #[must_use]
+    pub fn requires_ifs<T: Key>(mut self, ifs: &[(&'help str, T)]) -> Self {
+        self.requires.extend(
+            ifs.iter()
+                .map(|(val, arg)| (ArgPredicate::Equals(OsStr::new(*val)), Id::from(arg))),
+        );
+        self
+    }
+
+    /// Require these arguments names when this one is presen
+    ///
+    /// i.e. when using this argument, the following arguments *must* be present.
+    ///
+    /// **NOTE:** [Conflicting] rules and [override] rules take precedence over being required
+    /// by default.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .requires_all(&["input", "output"])
+    /// # ;
+    /// ```
+    ///
+    /// Setting `Arg::requires_all(&[arg, arg2])` requires that all the arguments be used at
+    /// runtime if the defining argument is used. If the defining argument isn't used, the other
+    /// argument isn't required
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .requires("input")
+    ///         .long("config"))
+    ///     .arg(Arg::new("input"))
+    ///     .arg(Arg::new("output"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog"
+    ///     ]);
+    ///
+    /// assert!(res.is_ok()); // We didn't use cfg, so input and output weren't required
+    /// ```
+    ///
+    /// Setting `Arg::requires_all(&[arg, arg2])` and *not* supplying all the arguments is an
+    /// error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .requires_all(&["input", "output"])
+    ///         .long("config"))
+    ///     .arg(Arg::new("input"))
+    ///     .arg(Arg::new("output"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--config", "file.conf", "in.txt"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// // We didn't use output
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [Conflicting]: Arg::conflicts_with()
+    /// [override]: Arg::overrides_with()
+    #[must_use]
+    pub fn requires_all<T: Key>(mut self, names: &[T]) -> Self {
+        self.requires
+            .extend(names.iter().map(|s| (ArgPredicate::IsPresent, s.into())));
+        self
+    }
+
+    /// This argument is mutually exclusive with the specified argument.
+    ///
+    /// **NOTE:** Conflicting rules take precedence over being required by default. Conflict rules
+    /// only need to be set for one of the two arguments, they do not need to be set for each.
+    ///
+    /// **NOTE:** Defining a conflict is two-way, but does *not* need to defined for both arguments
+    /// (i.e. if A conflicts with B, defining A.conflicts_with(B) is sufficient. You do not
+    /// need to also do B.conflicts_with(A))
+    ///
+    /// **NOTE:** [`Arg::conflicts_with_all(names)`] allows specifying an argument which conflicts with more than one argument.
+    ///
+    /// **NOTE** [`Arg::exclusive(true)`] allows specifying an argument which conflicts with every other argument.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .conflicts_with("debug")
+    /// # ;
+    /// ```
+    ///
+    /// Setting conflicting argument, and having both arguments present at runtime is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .conflicts_with("debug")
+    ///         .long("config"))
+    ///     .arg(Arg::new("debug")
+    ///         .long("debug"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--debug", "--config", "file.conf"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::ArgumentConflict);
+    /// ```
+    ///
+    /// [`Arg::conflicts_with_all(names)`]: Arg::conflicts_with_all()
+    /// [`Arg::exclusive(true)`]: Arg::exclusive()
+    #[must_use]
+    pub fn conflicts_with<T: Key>(mut self, arg_id: T) -> Self {
+        self.blacklist.push(arg_id.into());
+        self
+    }
+
+    /// This argument is mutually exclusive with the specified arguments.
+    ///
+    /// See [`Arg::conflicts_with`].
+    ///
+    /// **NOTE:** Conflicting rules take precedence over being required by default. Conflict rules
+    /// only need to be set for one of the two arguments, they do not need to be set for each.
+    ///
+    /// **NOTE:** Defining a conflict is two-way, but does *not* need to defined for both arguments
+    /// (i.e. if A conflicts with B, defining A.conflicts_with(B) is sufficient. You do not need
+    /// need to also do B.conflicts_with(A))
+    ///
+    /// **NOTE:** [`Arg::exclusive(true)`] allows specifying an argument which conflicts with every other argument.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// Arg::new("config")
+    ///     .conflicts_with_all(&["debug", "input"])
+    /// # ;
+    /// ```
+    ///
+    /// Setting conflicting argument, and having any of the arguments present at runtime with a
+    /// conflicting argument is an error.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("cfg")
+    ///         .takes_value(true)
+    ///         .conflicts_with_all(&["debug", "input"])
+    ///         .long("config"))
+    ///     .arg(Arg::new("debug")
+    ///         .long("debug"))
+    ///     .arg(Arg::new("input"))
+    ///     .try_get_matches_from(vec![
+    ///         "prog", "--config", "file.conf", "file.txt"
+    ///     ]);
+    ///
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::ArgumentConflict);
+    /// ```
+    /// [`Arg::conflicts_with`]: Arg::conflicts_with()
+    /// [`Arg::exclusive(true)`]: Arg::exclusive()
+    #[must_use]
+    pub fn conflicts_with_all(mut self, names: &[&str]) -> Self {
+        self.blacklist.extend(names.iter().copied().map(Id::from));
+        self
+    }
+
+    /// Sets an overridable argument.
+    ///
+    /// i.e. this argument and the following argument
+    /// will override each other in POSIX style (whichever argument was specified at runtime
+    /// **last** "wins")
+    ///
+    /// **NOTE:** When an argument is overridden it is essentially as if it never was used, any
+    /// conflicts, requirements, etc. are evaluated **after** all "overrides" have been removed
+    ///
+    /// **NOTE:** Overriding an argument implies they [conflict][Arg::conflicts_with`].
+    ///
+    /// **WARNING:** Positional arguments and options which accept
+    /// [`Arg::multiple_occurrences`] cannot override themselves (or we
+    /// would never be able to advance to the next positional). If a positional
+    /// argument or option with one of the [`Arg::multiple_occurrences`]
+    /// settings lists itself as an override, it is simply ignored.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, arg};
+    /// let m = Command::new("prog")
+    ///     .arg(arg!(-f --flag "some flag")
+    ///         .conflicts_with("debug"))
+    ///     .arg(arg!(-d --debug "other flag"))
+    ///     .arg(arg!(-c --color "third flag")
+    ///         .overrides_with("flag"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-f", "-d", "-c"]);
+    ///             //    ^~~~~~~~~~~~^~~~~ flag is overridden by color
+    ///
+    /// assert!(m.is_present("color"));
+    /// assert!(m.is_present("debug")); // even though flag conflicts with debug, it's as if flag
+    ///                                 // was never used because it was overridden with color
+    /// assert!(!m.is_present("flag"));
+    /// ```
+    /// Care must be taken when using this setting, and having an arg override with itself. This
+    /// is common practice when supporting things like shell aliases, config files, etc.
+    /// However, when combined with multiple values, it can get dicy.
+    /// Here is how clap handles such situations:
+    ///
+    /// When a flag overrides itself, it's as if the flag was only ever used once (essentially
+    /// preventing a "Unexpected multiple usage" error):
+    ///
+    /// ```rust
+    /// # use clap::{Command, arg};
+    /// let m = Command::new("posix")
+    ///             .arg(arg!(--flag  "some flag").overrides_with("flag"))
+    ///             .get_matches_from(vec!["posix", "--flag", "--flag"]);
+    /// assert!(m.is_present("flag"));
+    /// ```
+    ///
+    /// Making an arg [`Arg::multiple_occurrences`] and override itself
+    /// is essentially meaningless. Therefore clap ignores an override of self
+    /// if it's a flag and it already accepts multiple occurrences.
+    ///
+    /// ```
+    /// # use clap::{Command, arg};
+    /// let m = Command::new("posix")
+    ///             .arg(arg!(--flag ...  "some flag").overrides_with("flag"))
+    ///             .get_matches_from(vec!["", "--flag", "--flag", "--flag", "--flag"]);
+    /// assert!(m.is_present("flag"));
+    /// ```
+    ///
+    /// Now notice with options (which *do not* set
+    /// [`Arg::multiple_occurrences`]), it's as if only the last
+    /// occurrence happened.
+    ///
+    /// ```
+    /// # use clap::{Command, arg};
+    /// let m = Command::new("posix")
+    ///             .arg(arg!(--opt <val> "some option").overrides_with("opt"))
+    ///             .get_matches_from(vec!["", "--opt=some", "--opt=other"]);
+    /// assert!(m.is_present("opt"));
+    /// assert_eq!(m.value_of("opt"), Some("other"));
+    /// ```
+    ///
+    /// This will also work when [`Arg::multiple_values`] is enabled:
+    ///
+    /// ```
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("posix")
+    ///             .arg(
+    ///                 Arg::new("opt")
+    ///                     .long("opt")
+    ///                     .takes_value(true)
+    ///                     .multiple_values(true)
+    ///                     .overrides_with("opt")
+    ///             )
+    ///             .get_matches_from(vec!["", "--opt", "1", "2", "--opt", "3", "4", "5"]);
+    /// assert!(m.is_present("opt"));
+    /// assert_eq!(m.values_of("opt").unwrap().collect::<Vec<_>>(), &["3", "4", "5"]);
+    /// ```
+    ///
+    /// Just like flags, options with [`Arg::multiple_occurrences`] set
+    /// will ignore the "override self" setting.
+    ///
+    /// ```
+    /// # use clap::{Command, arg};
+    /// let m = Command::new("posix")
+    ///             .arg(arg!(--opt <val> ... "some option")
+    ///                 .multiple_values(true)
+    ///                 .overrides_with("opt"))
+    ///             .get_matches_from(vec!["", "--opt", "first", "over", "--opt", "other", "val"]);
+    /// assert!(m.is_present("opt"));
+    /// assert_eq!(m.values_of("opt").unwrap().collect::<Vec<_>>(), &["first", "over", "other", "val"]);
+    /// ```
+    #[must_use]
+    pub fn overrides_with<T: Key>(mut self, arg_id: T) -> Self {
+        self.overrides.push(arg_id.into());
+        self
+    }
+
+    /// Sets multiple mutually overridable arguments by name.
+    ///
+    /// i.e. this argument and the following argument will override each other in POSIX style
+    /// (whichever argument was specified at runtime **last** "wins")
+    ///
+    /// **NOTE:** When an argument is overridden it is essentially as if it never was used, any
+    /// conflicts, requirements, etc. are evaluated **after** all "overrides" have been removed
+    ///
+    /// **NOTE:** Overriding an argument implies they [conflict][Arg::conflicts_with_all`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, arg};
+    /// let m = Command::new("prog")
+    ///     .arg(arg!(-f --flag "some flag")
+    ///         .conflicts_with("color"))
+    ///     .arg(arg!(-d --debug "other flag"))
+    ///     .arg(arg!(-c --color "third flag")
+    ///         .overrides_with_all(&["flag", "debug"]))
+    ///     .get_matches_from(vec![
+    ///         "prog", "-f", "-d", "-c"]);
+    ///             //    ^~~~~~^~~~~~~~~ flag and debug are overridden by color
+    ///
+    /// assert!(m.is_present("color")); // even though flag conflicts with color, it's as if flag
+    ///                                 // and debug were never used because they were overridden
+    ///                                 // with color
+    /// assert!(!m.is_present("debug"));
+    /// assert!(!m.is_present("flag"));
+    /// ```
+    #[must_use]
+    pub fn overrides_with_all<T: Key>(mut self, names: &[T]) -> Self {
+        self.overrides.extend(names.iter().map(Id::from));
+        self
+    }
+}
+
+/// # Reflection
+impl<'help> Arg<'help> {
+    /// Get the name of the argument
+    #[inline]
+    pub fn get_id(&self) -> &'help str {
+        self.name
+    }
+
+    /// Deprecated, replaced with [`Arg::get_id`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Arg::get_id`")
+    )]
+    pub fn get_name(&self) -> &'help str {
+        self.get_id()
+    }
+
+    /// Get the help specified for this argument, if any
+    #[inline]
+    pub fn get_help(&self) -> Option<&'help str> {
+        self.help
+    }
+
+    /// Get the long help specified for this argument, if any
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// let arg = Arg::new("foo").long_help("long help");
+    /// assert_eq!(Some("long help"), arg.get_long_help());
+    /// ```
+    ///
+    #[inline]
+    pub fn get_long_help(&self) -> Option<&'help str> {
+        self.long_help
+    }
+
+    /// Get the help heading specified for this argument, if any
+    #[inline]
+    pub fn get_help_heading(&self) -> Option<&'help str> {
+        self.help_heading.unwrap_or_default()
+    }
+
+    /// Get the short option name for this argument, if any
+    #[inline]
+    pub fn get_short(&self) -> Option<char> {
+        self.short
+    }
+
+    /// Get visible short aliases for this argument, if any
+    #[inline]
+    pub fn get_visible_short_aliases(&self) -> Option<Vec<char>> {
+        if self.short_aliases.is_empty() {
+            None
+        } else {
+            Some(
+                self.short_aliases
+                    .iter()
+                    .filter_map(|(c, v)| if *v { Some(c) } else { None })
+                    .copied()
+                    .collect(),
+            )
+        }
+    }
+
+    /// Get *all* short aliases for this argument, if any, both visible and hidden.
+    #[inline]
+    pub fn get_all_short_aliases(&self) -> Option<Vec<char>> {
+        if self.short_aliases.is_empty() {
+            None
+        } else {
+            Some(self.short_aliases.iter().map(|(s, _)| s).copied().collect())
+        }
+    }
+
+    /// Get the short option name and its visible aliases, if any
+    #[inline]
+    pub fn get_short_and_visible_aliases(&self) -> Option<Vec<char>> {
+        let mut shorts = match self.short {
+            Some(short) => vec![short],
+            None => return None,
+        };
+        if let Some(aliases) = self.get_visible_short_aliases() {
+            shorts.extend(aliases);
+        }
+        Some(shorts)
+    }
+
+    /// Get the long option name for this argument, if any
+    #[inline]
+    pub fn get_long(&self) -> Option<&'help str> {
+        self.long
+    }
+
+    /// Get visible aliases for this argument, if any
+    #[inline]
+    pub fn get_visible_aliases(&self) -> Option<Vec<&'help str>> {
+        if self.aliases.is_empty() {
+            None
+        } else {
+            Some(
+                self.aliases
+                    .iter()
+                    .filter_map(|(s, v)| if *v { Some(s) } else { None })
+                    .copied()
+                    .collect(),
+            )
+        }
+    }
+
+    /// Get *all* aliases for this argument, if any, both visible and hidden.
+    #[inline]
+    pub fn get_all_aliases(&self) -> Option<Vec<&'help str>> {
+        if self.aliases.is_empty() {
+            None
+        } else {
+            Some(self.aliases.iter().map(|(s, _)| s).copied().collect())
+        }
+    }
+
+    /// Get the long option name and its visible aliases, if any
+    #[inline]
+    pub fn get_long_and_visible_aliases(&self) -> Option<Vec<&'help str>> {
+        let mut longs = match self.long {
+            Some(long) => vec![long],
+            None => return None,
+        };
+        if let Some(aliases) = self.get_visible_aliases() {
+            longs.extend(aliases);
+        }
+        Some(longs)
+    }
+
+    /// Deprecated, replaced with [`Arg::get_value_parser().possible_values()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Replaced with `Arg::get_value_parser().possible_values()`"
+        )
+    )]
+    pub fn get_possible_values(&self) -> Option<&[PossibleValue<'help>]> {
+        if self.possible_vals.is_empty() {
+            None
+        } else {
+            Some(&self.possible_vals)
+        }
+    }
+
+    pub(crate) fn get_possible_values2(&self) -> Vec<PossibleValue<'help>> {
+        #![allow(deprecated)]
+        if !self.is_takes_value_set() {
+            vec![]
+        } else if let Some(pvs) = self.get_possible_values() {
+            // Check old first in case the user explicitly set possible values and the derive inferred
+            // a `ValueParser` with some.
+            pvs.to_vec()
+        } else {
+            self.get_value_parser()
+                .possible_values()
+                .map(|pvs| pvs.collect())
+                .unwrap_or_default()
+        }
+    }
+
+    /// Get the names of values for this argument.
+    #[inline]
+    pub fn get_value_names(&self) -> Option<&[&'help str]> {
+        if self.val_names.is_empty() {
+            None
+        } else {
+            Some(&self.val_names)
+        }
+    }
+
+    /// Get the number of values for this argument.
+    #[inline]
+    pub fn get_num_vals(&self) -> Option<usize> {
+        self.num_vals
+    }
+
+    /// Get the delimiter between multiple values
+    #[inline]
+    pub fn get_value_delimiter(&self) -> Option<char> {
+        self.val_delim
+    }
+
+    /// Get the index of this argument, if any
+    #[inline]
+    pub fn get_index(&self) -> Option<usize> {
+        self.index
+    }
+
+    /// Get the value hint of this argument
+    pub fn get_value_hint(&self) -> ValueHint {
+        self.value_hint.unwrap_or_else(|| {
+            if self.is_takes_value_set() {
+                let type_id = self.get_value_parser().type_id();
+                if type_id == crate::parser::AnyValueId::of::<std::path::PathBuf>() {
+                    ValueHint::AnyPath
+                } else {
+                    ValueHint::default()
+                }
+            } else {
+                ValueHint::default()
+            }
+        })
+    }
+
+    /// Deprecated, replaced with [`Arg::is_global_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Arg::is_global_set`")
+    )]
+    pub fn get_global(&self) -> bool {
+        self.is_global_set()
+    }
+
+    /// Get the environment variable name specified for this argument, if any
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use std::ffi::OsStr;
+    /// # use clap::Arg;
+    /// let arg = Arg::new("foo").env("ENVIRONMENT");
+    /// assert_eq!(Some(OsStr::new("ENVIRONMENT")), arg.get_env());
+    /// ```
+    #[cfg(feature = "env")]
+    pub fn get_env(&self) -> Option<&OsStr> {
+        self.env.as_ref().map(|x| x.0)
+    }
+
+    /// Get the default values specified for this argument, if any
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Arg;
+    /// let arg = Arg::new("foo").default_value("default value");
+    /// assert_eq!(&["default value"], arg.get_default_values());
+    /// ```
+    pub fn get_default_values(&self) -> &[&OsStr] {
+        &self.default_vals
+    }
+
+    /// Checks whether this argument is a positional or not.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use clap::Arg;
+    /// let arg = Arg::new("foo");
+    /// assert_eq!(true, arg.is_positional());
+    ///
+    /// let arg = Arg::new("foo").long("foo");
+    /// assert_eq!(false, arg.is_positional());
+    /// ```
+    pub fn is_positional(&self) -> bool {
+        self.long.is_none() && self.short.is_none()
+    }
+
+    /// Reports whether [`Arg::required`] is set
+    pub fn is_required_set(&self) -> bool {
+        self.is_set(ArgSettings::Required)
+    }
+
+    /// Report whether [`Arg::multiple_values`] is set
+    pub fn is_multiple_values_set(&self) -> bool {
+        self.is_set(ArgSettings::MultipleValues)
+    }
+
+    /// [`Arg::multiple_occurrences`] is going away  ([Issue #3772](https://github.com/clap-rs/clap/issues/3772))
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "`multiple_occurrences` away (Issue #3772)")
+    )]
+    pub fn is_multiple_occurrences_set(&self) -> bool {
+        self.is_set(ArgSettings::MultipleOccurrences)
+    }
+
+    /// Report whether [`Arg::is_takes_value_set`] is set
+    pub fn is_takes_value_set(&self) -> bool {
+        self.is_set(ArgSettings::TakesValue)
+    }
+
+    /// Report whether [`Arg::allow_hyphen_values`] is set
+    pub fn is_allow_hyphen_values_set(&self) -> bool {
+        self.is_set(ArgSettings::AllowHyphenValues)
+    }
+
+    /// Deprecated, replaced with [`Arg::get_value_parser()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `Arg::get_value_parser()`")
+    )]
+    pub fn is_forbid_empty_values_set(&self) -> bool {
+        self.is_set(ArgSettings::ForbidEmptyValues)
+    }
+
+    /// Deprecated, replaced with [`Arg::get_value_parser()`
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `Arg::get_value_parser()`")
+    )]
+    pub fn is_allow_invalid_utf8_set(&self) -> bool {
+        self.is_set(ArgSettings::AllowInvalidUtf8)
+    }
+
+    /// Behavior when parsing the argument
+    pub fn get_action(&self) -> &super::ArgAction {
+        const DEFAULT: super::ArgAction = super::ArgAction::StoreValue;
+        self.action.as_ref().unwrap_or(&DEFAULT)
+    }
+
+    /// Configured parser for argument values
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// let cmd = clap::Command::new("raw")
+    ///     .arg(
+    ///         clap::Arg::new("port")
+    ///             .value_parser(clap::value_parser!(usize))
+    ///     );
+    /// let value_parser = cmd.get_arguments()
+    ///     .find(|a| a.get_id() == "port").unwrap()
+    ///     .get_value_parser();
+    /// println!("{:?}", value_parser);
+    /// ```
+    pub fn get_value_parser(&self) -> &super::ValueParser {
+        if let Some(value_parser) = self.value_parser.as_ref() {
+            value_parser
+        } else if self.is_allow_invalid_utf8_set() {
+            static DEFAULT: super::ValueParser = super::ValueParser::os_string();
+            &DEFAULT
+        } else {
+            static DEFAULT: super::ValueParser = super::ValueParser::string();
+            &DEFAULT
+        }
+    }
+
+    /// Report whether [`Arg::global`] is set
+    pub fn is_global_set(&self) -> bool {
+        self.is_set(ArgSettings::Global)
+    }
+
+    /// Report whether [`Arg::next_line_help`] is set
+    pub fn is_next_line_help_set(&self) -> bool {
+        self.is_set(ArgSettings::NextLineHelp)
+    }
+
+    /// Report whether [`Arg::hide`] is set
+    pub fn is_hide_set(&self) -> bool {
+        self.is_set(ArgSettings::Hidden)
+    }
+
+    /// Report whether [`Arg::hide_default_value`] is set
+    pub fn is_hide_default_value_set(&self) -> bool {
+        self.is_set(ArgSettings::HideDefaultValue)
+    }
+
+    /// Report whether [`Arg::hide_possible_values`] is set
+    pub fn is_hide_possible_values_set(&self) -> bool {
+        self.is_set(ArgSettings::HidePossibleValues)
+    }
+
+    /// Report whether [`Arg::hide_env`] is set
+    #[cfg(feature = "env")]
+    pub fn is_hide_env_set(&self) -> bool {
+        self.is_set(ArgSettings::HideEnv)
+    }
+
+    /// Report whether [`Arg::hide_env_values`] is set
+    #[cfg(feature = "env")]
+    pub fn is_hide_env_values_set(&self) -> bool {
+        self.is_set(ArgSettings::HideEnvValues)
+    }
+
+    /// Report whether [`Arg::hide_short_help`] is set
+    pub fn is_hide_short_help_set(&self) -> bool {
+        self.is_set(ArgSettings::HiddenShortHelp)
+    }
+
+    /// Report whether [`Arg::hide_long_help`] is set
+    pub fn is_hide_long_help_set(&self) -> bool {
+        self.is_set(ArgSettings::HiddenLongHelp)
+    }
+
+    /// Report whether [`Arg::use_value_delimiter`] is set
+    pub fn is_use_value_delimiter_set(&self) -> bool {
+        self.is_set(ArgSettings::UseValueDelimiter)
+    }
+
+    /// Report whether [`Arg::require_value_delimiter`] is set
+    pub fn is_require_value_delimiter_set(&self) -> bool {
+        self.is_set(ArgSettings::RequireDelimiter)
+    }
+
+    /// Report whether [`Arg::require_equals`] is set
+    pub fn is_require_equals_set(&self) -> bool {
+        self.is_set(ArgSettings::RequireEquals)
+    }
+
+    /// Reports whether [`Arg::exclusive`] is set
+    pub fn is_exclusive_set(&self) -> bool {
+        self.is_set(ArgSettings::Exclusive)
+    }
+
+    /// Reports whether [`Arg::last`] is set
+    pub fn is_last_set(&self) -> bool {
+        self.is_set(ArgSettings::Last)
+    }
+
+    /// Reports whether [`Arg::ignore_case`] is set
+    pub fn is_ignore_case_set(&self) -> bool {
+        self.is_set(ArgSettings::IgnoreCase)
+    }
+}
+
+/// # Deprecated
+impl<'help> Arg<'help> {
+    /// Deprecated, replaced with [`Arg::new`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::new`")
+    )]
+    #[doc(hidden)]
+    pub fn with_name<S: Into<&'help str>>(n: S) -> Self {
+        Self::new(n)
+    }
+
+    /// Deprecated in [Issue #3087](https://github.com/clap-rs/clap/issues/3087), maybe [`clap::Parser`][crate::Parser] would fit your use case?
+    #[cfg(feature = "yaml")]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Deprecated in Issue #3087, maybe clap::Parser would fit your use case?"
+        )
+    )]
+    #[doc(hidden)]
+    pub fn from_yaml(y: &'help Yaml) -> Self {
+        #![allow(deprecated)]
+        let yaml_file_hash = y.as_hash().expect("YAML file must be a hash");
+        // We WANT this to panic on error...so expect() is good.
+        let (name_yaml, yaml) = yaml_file_hash
+            .iter()
+            .next()
+            .expect("There must be one arg in the YAML file");
+        let name_str = name_yaml.as_str().expect("Arg name must be a string");
+        let mut a = Arg::new(name_str);
+
+        for (k, v) in yaml.as_hash().expect("Arg must be a hash") {
+            a = match k.as_str().expect("Arg fields must be strings") {
+                "short" => yaml_to_char!(a, v, short),
+                "long" => yaml_to_str!(a, v, long),
+                "aliases" => yaml_vec_or_str!(a, v, alias),
+                "help" => yaml_to_str!(a, v, help),
+                "long_help" => yaml_to_str!(a, v, long_help),
+                "required" => yaml_to_bool!(a, v, required),
+                "required_if" => yaml_tuple2!(a, v, required_if_eq),
+                "required_ifs" => yaml_tuple2!(a, v, required_if_eq),
+                "takes_value" => yaml_to_bool!(a, v, takes_value),
+                "index" => yaml_to_usize!(a, v, index),
+                "global" => yaml_to_bool!(a, v, global),
+                "multiple" => yaml_to_bool!(a, v, multiple),
+                "hidden" => yaml_to_bool!(a, v, hide),
+                "next_line_help" => yaml_to_bool!(a, v, next_line_help),
+                "group" => yaml_to_str!(a, v, group),
+                "number_of_values" => yaml_to_usize!(a, v, number_of_values),
+                "max_values" => yaml_to_usize!(a, v, max_values),
+                "min_values" => yaml_to_usize!(a, v, min_values),
+                "value_name" => yaml_to_str!(a, v, value_name),
+                "use_delimiter" => yaml_to_bool!(a, v, use_delimiter),
+                "allow_hyphen_values" => yaml_to_bool!(a, v, allow_hyphen_values),
+                "last" => yaml_to_bool!(a, v, last),
+                "require_delimiter" => yaml_to_bool!(a, v, require_delimiter),
+                "value_delimiter" => yaml_to_char!(a, v, value_delimiter),
+                "required_unless" => yaml_to_str!(a, v, required_unless_present),
+                "display_order" => yaml_to_usize!(a, v, display_order),
+                "default_value" => yaml_to_str!(a, v, default_value),
+                "default_value_if" => yaml_tuple3!(a, v, default_value_if),
+                "default_value_ifs" => yaml_tuple3!(a, v, default_value_if),
+                #[cfg(feature = "env")]
+                "env" => yaml_to_str!(a, v, env),
+                "value_names" => yaml_vec_or_str!(a, v, value_name),
+                "groups" => yaml_vec_or_str!(a, v, group),
+                "requires" => yaml_vec_or_str!(a, v, requires),
+                "requires_if" => yaml_tuple2!(a, v, requires_if),
+                "requires_ifs" => yaml_tuple2!(a, v, requires_if),
+                "conflicts_with" => yaml_vec_or_str!(a, v, conflicts_with),
+                "overrides_with" => yaml_to_str!(a, v, overrides_with),
+                "possible_values" => yaml_vec_or_str!(a, v, possible_value),
+                "case_insensitive" => yaml_to_bool!(a, v, ignore_case),
+                "required_unless_one" => yaml_vec!(a, v, required_unless_present_any),
+                "required_unless_all" => yaml_vec!(a, v, required_unless_present_all),
+                s => {
+                    panic!(
+                        "Unknown setting '{}' in YAML file for arg '{}'",
+                        s, name_str
+                    )
+                }
+            }
+        }
+
+        a
+    }
+
+    /// Deprecated in [Issue #3086](https://github.com/clap-rs/clap/issues/3086), see [`arg!`][crate::arg!].
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Deprecated in Issue #3086, see `clap::arg!")
+    )]
+    #[doc(hidden)]
+    pub fn from_usage(u: &'help str) -> Self {
+        UsageParser::from_usage(u).parse()
+    }
+
+    /// Deprecated, replaced with [`Arg::required_unless_present`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::required_unless_present`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn required_unless<T: Key>(self, arg_id: T) -> Self {
+        self.required_unless_present(arg_id)
+    }
+
+    /// Deprecated, replaced with [`Arg::required_unless_present_all`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `Arg::required_unless_present_all`"
+        )
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn required_unless_all<T, I>(self, names: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Key,
+    {
+        self.required_unless_present_all(names)
+    }
+
+    /// Deprecated, replaced with [`Arg::required_unless_present_any`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `Arg::required_unless_present_any`"
+        )
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn required_unless_one<T, I>(self, names: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Key,
+    {
+        self.required_unless_present_any(names)
+    }
+
+    /// Deprecated, replaced with [`Arg::required_if_eq`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::required_if_eq`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn required_if<T: Key>(self, arg_id: T, val: &'help str) -> Self {
+        self.required_if_eq(arg_id, val)
+    }
+
+    /// Deprecated, replaced with [`Arg::required_if_eq_any`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::required_if_eq_any`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn required_ifs<T: Key>(self, ifs: &[(T, &'help str)]) -> Self {
+        self.required_if_eq_any(ifs)
+    }
+
+    /// Deprecated, replaced with [`Arg::hide`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::hide`")
+    )]
+    #[doc(hidden)]
+    #[inline]
+    #[must_use]
+    pub fn hidden(self, yes: bool) -> Self {
+        self.hide(yes)
+    }
+
+    /// Deprecated, replaced with [`Arg::ignore_case`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::ignore_case`")
+    )]
+    #[doc(hidden)]
+    #[inline]
+    #[must_use]
+    pub fn case_insensitive(self, yes: bool) -> Self {
+        self.ignore_case(yes)
+    }
+
+    /// Deprecated, replaced with [`Arg::forbid_empty_values`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::forbid_empty_values`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn empty_values(self, yes: bool) -> Self {
+        self.forbid_empty_values(!yes)
+    }
+
+    /// Deprecated, replaced with [`Arg::multiple_occurrences`] (most likely what you want) and
+    /// [`Arg::multiple_values`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Split into `Arg::multiple_occurrences` (most likely what you want)  and `Arg::multiple_values`"
+        )
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn multiple(self, yes: bool) -> Self {
+        self.multiple_occurrences(yes).multiple_values(yes)
+    }
+
+    /// Deprecated, replaced with [`Arg::hide_short_help`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::hide_short_help`")
+    )]
+    #[doc(hidden)]
+    #[inline]
+    #[must_use]
+    pub fn hidden_short_help(self, yes: bool) -> Self {
+        self.hide_short_help(yes)
+    }
+
+    /// Deprecated, replaced with [`Arg::hide_long_help`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::hide_long_help`")
+    )]
+    #[doc(hidden)]
+    #[inline]
+    #[must_use]
+    pub fn hidden_long_help(self, yes: bool) -> Self {
+        self.hide_long_help(yes)
+    }
+
+    /// Deprecated, replaced with [`Arg::setting`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::setting`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn set(self, s: ArgSettings) -> Self {
+        self.setting(s)
+    }
+
+    /// Deprecated, replaced with [`Arg::unset_setting`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Arg::unset_setting`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn unset(self, s: ArgSettings) -> Self {
+        self.unset_setting(s)
+    }
+}
+
+/// # Internally used only
+impl<'help> Arg<'help> {
+    pub(crate) fn _build(&mut self) {
+        if self.is_positional() {
+            self.settings.set(ArgSettings::TakesValue);
+        }
+        if let Some(action) = self.action.as_ref() {
+            if let Some(default_value) = action.default_value() {
+                if self.default_vals.is_empty() {
+                    self.default_vals = vec![default_value];
+                }
+            }
+            if action.takes_values() {
+                self.settings.set(ArgSettings::TakesValue);
+            } else {
+                self.settings.unset(ArgSettings::TakesValue);
+            }
+            match action {
+                ArgAction::StoreValue
+                | ArgAction::IncOccurrence
+                | ArgAction::Help
+                | ArgAction::Version => {}
+                ArgAction::Set
+                | ArgAction::Append
+                | ArgAction::SetTrue
+                | ArgAction::SetFalse
+                | ArgAction::Count => {
+                    if !self.is_positional() {
+                        self.settings.set(ArgSettings::MultipleOccurrences);
+                    }
+                }
+            }
+        }
+
+        if self.value_parser.is_none() {
+            if let Some(default) = self.action.as_ref().and_then(|a| a.default_value_parser()) {
+                self.value_parser = Some(default);
+            } else if self.is_allow_invalid_utf8_set() {
+                self.value_parser = Some(super::ValueParser::os_string());
+            } else {
+                self.value_parser = Some(super::ValueParser::string());
+            }
+        }
+
+        if (self.is_use_value_delimiter_set() || self.is_require_value_delimiter_set())
+            && self.val_delim.is_none()
+        {
+            self.val_delim = Some(',');
+        }
+
+        let val_names_len = self.val_names.len();
+
+        if val_names_len > 1 {
+            self.settings.set(ArgSettings::MultipleValues);
+
+            if self.num_vals.is_none() {
+                self.num_vals = Some(val_names_len);
+            }
+        }
+
+        let self_id = self.id.clone();
+        if self.is_positional() || self.is_multiple_occurrences_set() {
+            // Remove self-overrides where they don't make sense.
+            //
+            // We can evaluate switching this to a debug assert at a later time (though it will
+            // require changing propagation of `AllArgsOverrideSelf`).  Being conservative for now
+            // due to where we are at in the release.
+            self.overrides.retain(|e| *e != self_id);
+        }
+    }
+
+    pub(crate) fn generated(mut self) -> Self {
+        self.provider = ArgProvider::Generated;
+        self
+    }
+
+    pub(crate) fn longest_filter(&self) -> bool {
+        self.is_takes_value_set() || self.long.is_some() || self.short.is_none()
+    }
+
+    // Used for positionals when printing
+    pub(crate) fn multiple_str(&self) -> &str {
+        let mult_vals = self.val_names.len() > 1;
+        if (self.is_multiple_values_set() || self.is_multiple_occurrences_set()) && !mult_vals {
+            "..."
+        } else {
+            ""
+        }
+    }
+
+    // Used for positionals when printing
+    pub(crate) fn name_no_brackets(&self) -> Cow<str> {
+        debug!("Arg::name_no_brackets:{}", self.name);
+        let delim = if self.is_require_value_delimiter_set() {
+            self.val_delim.expect(INTERNAL_ERROR_MSG)
+        } else {
+            ' '
+        }
+        .to_string();
+        if !self.val_names.is_empty() {
+            debug!("Arg::name_no_brackets: val_names={:#?}", self.val_names);
+
+            if self.val_names.len() > 1 {
+                Cow::Owned(
+                    self.val_names
+                        .iter()
+                        .map(|n| format!("<{}>", n))
+                        .collect::<Vec<_>>()
+                        .join(&*delim),
+                )
+            } else {
+                Cow::Borrowed(self.val_names.get(0).expect(INTERNAL_ERROR_MSG))
+            }
+        } else {
+            debug!("Arg::name_no_brackets: just name");
+            Cow::Borrowed(self.name)
+        }
+    }
+
+    /// Either multiple values or occurrences
+    pub(crate) fn is_multiple(&self) -> bool {
+        self.is_multiple_values_set() | self.is_multiple_occurrences_set()
+    }
+
+    pub(crate) fn get_display_order(&self) -> usize {
+        self.disp_ord.get_explicit()
+    }
+}
+
+impl<'help> From<&'_ Arg<'help>> for Arg<'help> {
+    fn from(a: &Arg<'help>) -> Self {
+        a.clone()
+    }
+}
+
+impl<'help> PartialEq for Arg<'help> {
+    fn eq(&self, other: &Arg<'help>) -> bool {
+        self.name == other.name
+    }
+}
+
+impl<'help> PartialOrd for Arg<'help> {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+impl<'help> Ord for Arg<'help> {
+    fn cmp(&self, other: &Arg) -> Ordering {
+        self.name.cmp(other.name)
+    }
+}
+
+impl<'help> Eq for Arg<'help> {}
+
+impl<'help> Display for Arg<'help> {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        // Write the name such --long or -l
+        if let Some(l) = self.long {
+            write!(f, "--{}", l)?;
+        } else if let Some(s) = self.short {
+            write!(f, "-{}", s)?;
+        }
+        let mut need_closing_bracket = false;
+        if !self.is_positional() && self.is_takes_value_set() {
+            let is_optional_val = self.min_vals == Some(0);
+            let sep = if self.is_require_equals_set() {
+                if is_optional_val {
+                    need_closing_bracket = true;
+                    "[="
+                } else {
+                    "="
+                }
+            } else if is_optional_val {
+                need_closing_bracket = true;
+                " ["
+            } else {
+                " "
+            };
+            f.write_str(sep)?;
+        }
+        if self.is_takes_value_set() || self.is_positional() {
+            display_arg_val(self, |s, _| f.write_str(s))?;
+        }
+        if need_closing_bracket {
+            f.write_str("]")?;
+        }
+
+        Ok(())
+    }
+}
+
+impl<'help> fmt::Debug for Arg<'help> {
+    fn fmt(&self, f: &mut Formatter) -> Result<(), fmt::Error> {
+        let mut ds = f.debug_struct("Arg");
+
+        #[allow(unused_mut)]
+        let mut ds = ds
+            .field("id", &self.id)
+            .field("provider", &self.provider)
+            .field("name", &self.name)
+            .field("help", &self.help)
+            .field("long_help", &self.long_help)
+            .field("action", &self.action)
+            .field("value_parser", &self.value_parser)
+            .field("blacklist", &self.blacklist)
+            .field("settings", &self.settings)
+            .field("overrides", &self.overrides)
+            .field("groups", &self.groups)
+            .field("requires", &self.requires)
+            .field("r_ifs", &self.r_ifs)
+            .field("r_unless", &self.r_unless)
+            .field("short", &self.short)
+            .field("long", &self.long)
+            .field("aliases", &self.aliases)
+            .field("short_aliases", &self.short_aliases)
+            .field("disp_ord", &self.disp_ord)
+            .field("possible_vals", &self.possible_vals)
+            .field("val_names", &self.val_names)
+            .field("num_vals", &self.num_vals)
+            .field("max_vals", &self.max_vals)
+            .field("min_vals", &self.min_vals)
+            .field(
+                "validator",
+                &self.validator.as_ref().map_or("None", |_| "Some(FnMut)"),
+            )
+            .field(
+                "validator_os",
+                &self.validator_os.as_ref().map_or("None", |_| "Some(FnMut)"),
+            )
+            .field("val_delim", &self.val_delim)
+            .field("default_vals", &self.default_vals)
+            .field("default_vals_ifs", &self.default_vals_ifs)
+            .field("terminator", &self.terminator)
+            .field("index", &self.index)
+            .field("help_heading", &self.help_heading)
+            .field("value_hint", &self.value_hint)
+            .field("default_missing_vals", &self.default_missing_vals);
+
+        #[cfg(feature = "env")]
+        {
+            ds = ds.field("env", &self.env);
+        }
+
+        ds.finish()
+    }
+}
+
+type Validator<'a> = dyn FnMut(&str) -> Result<(), Box<dyn Error + Send + Sync>> + Send + 'a;
+type ValidatorOs<'a> = dyn FnMut(&OsStr) -> Result<(), Box<dyn Error + Send + Sync>> + Send + 'a;
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub(crate) enum ArgProvider {
+    Generated,
+    GeneratedMutated,
+    User,
+}
+
+impl Default for ArgProvider {
+    fn default() -> Self {
+        ArgProvider::User
+    }
+}
+
+/// Write the values such as <name1> <name2>
+pub(crate) fn display_arg_val<F, T, E>(arg: &Arg, mut write: F) -> Result<(), E>
+where
+    F: FnMut(&str, bool) -> Result<T, E>,
+{
+    let mult_val = arg.is_multiple_values_set();
+    let mult_occ = arg.is_multiple_occurrences_set();
+    let delim = if arg.is_require_value_delimiter_set() {
+        arg.val_delim.expect(INTERNAL_ERROR_MSG)
+    } else {
+        ' '
+    }
+    .to_string();
+    if !arg.val_names.is_empty() {
+        // If have val_name.
+        match (arg.val_names.len(), arg.num_vals) {
+            (1, Some(num_vals)) => {
+                // If single value name with multiple num_of_vals, display all
+                // the values with the single value name.
+                let arg_name = format!("<{}>", arg.val_names.get(0).unwrap());
+                for n in 1..=num_vals {
+                    write(&arg_name, true)?;
+                    if n != num_vals {
+                        write(&delim, false)?;
+                    }
+                }
+            }
+            (num_val_names, _) => {
+                // If multiple value names, display them sequentially(ignore num of vals).
+                let mut it = arg.val_names.iter().peekable();
+                while let Some(val) = it.next() {
+                    write(&format!("<{}>", val), true)?;
+                    if it.peek().is_some() {
+                        write(&delim, false)?;
+                    }
+                }
+                if (num_val_names == 1 && mult_val)
+                    || (arg.is_positional() && mult_occ)
+                    || num_val_names < arg.num_vals.unwrap_or(0)
+                {
+                    write("...", true)?;
+                }
+            }
+        }
+    } else if let Some(num_vals) = arg.num_vals {
+        // If number_of_values is specified, display the value multiple times.
+        let arg_name = format!("<{}>", arg.name);
+        for n in 1..=num_vals {
+            write(&arg_name, true)?;
+            if n != num_vals {
+                write(&delim, false)?;
+            }
+        }
+    } else if arg.is_positional() {
+        // Value of positional argument with no num_vals and val_names.
+        write(&format!("<{}>", arg.name), true)?;
+
+        if mult_val || mult_occ {
+            write("...", true)?;
+        }
+    } else {
+        // value of flag argument with no num_vals and val_names.
+        write(&format!("<{}>", arg.name), true)?;
+        if mult_val {
+            write("...", true)?;
+        }
+    }
+    Ok(())
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
+pub(crate) enum DisplayOrder {
+    None,
+    Implicit(usize),
+    Explicit(usize),
+}
+
+impl DisplayOrder {
+    pub(crate) fn set_explicit(&mut self, explicit: usize) {
+        *self = Self::Explicit(explicit)
+    }
+
+    pub(crate) fn set_implicit(&mut self, implicit: usize) {
+        *self = (*self).max(Self::Implicit(implicit))
+    }
+
+    pub(crate) fn make_explicit(&mut self) {
+        match *self {
+            Self::None | Self::Explicit(_) => {}
+            Self::Implicit(disp) => self.set_explicit(disp),
+        }
+    }
+
+    pub(crate) fn get_explicit(self) -> usize {
+        match self {
+            Self::None | Self::Implicit(_) => 999,
+            Self::Explicit(disp) => disp,
+        }
+    }
+}
+
+impl Default for DisplayOrder {
+    fn default() -> Self {
+        Self::None
+    }
+}
+
+// Flags
+#[cfg(test)]
+mod test {
+    use super::Arg;
+
+    #[test]
+    fn flag_display() {
+        let mut f = Arg::new("flg").multiple_occurrences(true);
+        f.long = Some("flag");
+
+        assert_eq!(f.to_string(), "--flag");
+
+        let mut f2 = Arg::new("flg");
+        f2.short = Some('f');
+
+        assert_eq!(f2.to_string(), "-f");
+    }
+
+    #[test]
+    fn flag_display_single_alias() {
+        let mut f = Arg::new("flg");
+        f.long = Some("flag");
+        f.aliases = vec![("als", true)];
+
+        assert_eq!(f.to_string(), "--flag")
+    }
+
+    #[test]
+    fn flag_display_multiple_aliases() {
+        let mut f = Arg::new("flg");
+        f.short = Some('f');
+        f.aliases = vec![
+            ("alias_not_visible", false),
+            ("f2", true),
+            ("f3", true),
+            ("f4", true),
+        ];
+        assert_eq!(f.to_string(), "-f");
+    }
+
+    #[test]
+    fn flag_display_single_short_alias() {
+        let mut f = Arg::new("flg");
+        f.short = Some('a');
+        f.short_aliases = vec![('b', true)];
+
+        assert_eq!(f.to_string(), "-a")
+    }
+
+    #[test]
+    fn flag_display_multiple_short_aliases() {
+        let mut f = Arg::new("flg");
+        f.short = Some('a');
+        f.short_aliases = vec![('b', false), ('c', true), ('d', true), ('e', true)];
+        assert_eq!(f.to_string(), "-a");
+    }
+
+    // Options
+
+    #[test]
+    fn option_display_multiple_occurrences() {
+        let o = Arg::new("opt")
+            .long("option")
+            .takes_value(true)
+            .multiple_occurrences(true);
+
+        assert_eq!(o.to_string(), "--option <opt>");
+    }
+
+    #[test]
+    fn option_display_multiple_values() {
+        let o = Arg::new("opt")
+            .long("option")
+            .takes_value(true)
+            .multiple_values(true);
+
+        assert_eq!(o.to_string(), "--option <opt>...");
+    }
+
+    #[test]
+    fn option_display2() {
+        let o2 = Arg::new("opt").short('o').value_names(&["file", "name"]);
+
+        assert_eq!(o2.to_string(), "-o <file> <name>");
+    }
+
+    #[test]
+    fn option_display3() {
+        let o2 = Arg::new("opt")
+            .short('o')
+            .takes_value(true)
+            .multiple_values(true)
+            .value_names(&["file", "name"]);
+
+        assert_eq!(o2.to_string(), "-o <file> <name>");
+    }
+
+    #[test]
+    fn option_display_single_alias() {
+        let o = Arg::new("opt")
+            .takes_value(true)
+            .long("option")
+            .visible_alias("als");
+
+        assert_eq!(o.to_string(), "--option <opt>");
+    }
+
+    #[test]
+    fn option_display_multiple_aliases() {
+        let o = Arg::new("opt")
+            .long("option")
+            .takes_value(true)
+            .visible_aliases(&["als2", "als3", "als4"])
+            .alias("als_not_visible");
+
+        assert_eq!(o.to_string(), "--option <opt>");
+    }
+
+    #[test]
+    fn option_display_single_short_alias() {
+        let o = Arg::new("opt")
+            .takes_value(true)
+            .short('a')
+            .visible_short_alias('b');
+
+        assert_eq!(o.to_string(), "-a <opt>");
+    }
+
+    #[test]
+    fn option_display_multiple_short_aliases() {
+        let o = Arg::new("opt")
+            .short('a')
+            .takes_value(true)
+            .visible_short_aliases(&['b', 'c', 'd'])
+            .short_alias('e');
+
+        assert_eq!(o.to_string(), "-a <opt>");
+    }
+
+    // Positionals
+
+    #[test]
+    fn positional_display_multiple_values() {
+        let p = Arg::new("pos")
+            .index(1)
+            .takes_value(true)
+            .multiple_values(true);
+
+        assert_eq!(p.to_string(), "<pos>...");
+    }
+
+    #[test]
+    fn positional_display_multiple_occurrences() {
+        let p = Arg::new("pos")
+            .index(1)
+            .takes_value(true)
+            .multiple_occurrences(true);
+
+        assert_eq!(p.to_string(), "<pos>...");
+    }
+
+    #[test]
+    fn positional_display_required() {
+        let p2 = Arg::new("pos").index(1).required(true);
+
+        assert_eq!(p2.to_string(), "<pos>");
+    }
+
+    #[test]
+    fn positional_display_val_names() {
+        let p2 = Arg::new("pos").index(1).value_names(&["file1", "file2"]);
+
+        assert_eq!(p2.to_string(), "<file1> <file2>");
+    }
+
+    #[test]
+    fn positional_display_val_names_req() {
+        let p2 = Arg::new("pos")
+            .index(1)
+            .required(true)
+            .value_names(&["file1", "file2"]);
+
+        assert_eq!(p2.to_string(), "<file1> <file2>");
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/arg_group.rs b/vendor/clap-3.2.20/src/builder/arg_group.rs
new file mode 100644
index 000000000..0fe317109
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/arg_group.rs
@@ -0,0 +1,633 @@
+// Internal
+use crate::util::{Id, Key};
+
+#[cfg(feature = "yaml")]
+use yaml_rust::Yaml;
+
+/// Family of related [arguments].
+///
+/// By placing arguments in a logical group, you can create easier requirement and
+/// exclusion rules instead of having to list each argument individually, or when you want a rule
+/// to apply "any but not all" arguments.
+///
+/// For instance, you can make an entire `ArgGroup` required. If [`ArgGroup::multiple(true)`] is
+/// set, this means that at least one argument from that group must be present. If
+/// [`ArgGroup::multiple(false)`] is set (the default), one and *only* one must be present.
+///
+/// You can also do things such as name an entire `ArgGroup` as a [conflict] or [requirement] for
+/// another argument, meaning any of the arguments that belong to that group will cause a failure
+/// if present, or must be present respectively.
+///
+/// Perhaps the most common use of `ArgGroup`s is to require one and *only* one argument to be
+/// present out of a given set. Imagine that you had multiple arguments, and you want one of them
+/// to be required, but making all of them required isn't feasible because perhaps they conflict
+/// with each other. For example, lets say that you were building an application where one could
+/// set a given version number by supplying a string with an option argument, i.e.
+/// `--set-ver v1.2.3`, you also wanted to support automatically using a previous version number
+/// and simply incrementing one of the three numbers. So you create three flags `--major`,
+/// `--minor`, and `--patch`. All of these arguments shouldn't be used at one time but you want to
+/// specify that *at least one* of them is used. For this, you can create a group.
+///
+/// Finally, you may use `ArgGroup`s to pull a value from a group of arguments when you don't care
+/// exactly which argument was actually used at runtime.
+///
+/// # Examples
+///
+/// The following example demonstrates using an `ArgGroup` to ensure that one, and only one, of
+/// the arguments from the specified group is present at runtime.
+///
+/// ```rust
+/// # use clap::{Command, arg, ArgGroup, ErrorKind};
+/// let result = Command::new("cmd")
+///     .arg(arg!(--"set-ver" <ver> "set the version manually").required(false))
+///     .arg(arg!(--major           "auto increase major"))
+///     .arg(arg!(--minor           "auto increase minor"))
+///     .arg(arg!(--patch           "auto increase patch"))
+///     .group(ArgGroup::new("vers")
+///          .args(&["set-ver", "major", "minor", "patch"])
+///          .required(true))
+///     .try_get_matches_from(vec!["cmd", "--major", "--patch"]);
+/// // Because we used two args in the group it's an error
+/// assert!(result.is_err());
+/// let err = result.unwrap_err();
+/// assert_eq!(err.kind(), ErrorKind::ArgumentConflict);
+/// ```
+/// This next example shows a passing parse of the same scenario
+///
+/// ```rust
+/// # use clap::{Command, arg, ArgGroup};
+/// let result = Command::new("cmd")
+///     .arg(arg!(--"set-ver" <ver> "set the version manually").required(false))
+///     .arg(arg!(--major           "auto increase major"))
+///     .arg(arg!(--minor           "auto increase minor"))
+///     .arg(arg!(--patch           "auto increase patch"))
+///     .group(ArgGroup::new("vers")
+///          .args(&["set-ver", "major", "minor","patch"])
+///          .required(true))
+///     .try_get_matches_from(vec!["cmd", "--major"]);
+/// assert!(result.is_ok());
+/// let matches = result.unwrap();
+/// // We may not know which of the args was used, so we can test for the group...
+/// assert!(matches.contains_id("vers"));
+/// // we could also alternatively check each arg individually (not shown here)
+/// ```
+/// [`ArgGroup::multiple(true)`]: ArgGroup::multiple()
+///
+/// [`ArgGroup::multiple(false)`]: ArgGroup::multiple()
+/// [arguments]: crate::Arg
+/// [conflict]: crate::Arg::conflicts_with()
+/// [requirement]: crate::Arg::requires()
+#[derive(Default, Debug, PartialEq, Eq)]
+pub struct ArgGroup<'help> {
+    pub(crate) id: Id,
+    pub(crate) name: &'help str,
+    pub(crate) args: Vec<Id>,
+    pub(crate) required: bool,
+    pub(crate) requires: Vec<Id>,
+    pub(crate) conflicts: Vec<Id>,
+    pub(crate) multiple: bool,
+}
+
+impl<'help> ArgGroup<'help> {
+    pub(crate) fn with_id(id: Id) -> Self {
+        ArgGroup {
+            id,
+            ..ArgGroup::default()
+        }
+    }
+
+    /// Create a `ArgGroup` using a unique name.
+    ///
+    /// The name will be used to get values from the group or refer to the group inside of conflict
+    /// and requirement rules.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, ArgGroup};
+    /// ArgGroup::new("config")
+    /// # ;
+    /// ```
+    pub fn new<S: Into<&'help str>>(n: S) -> Self {
+        ArgGroup::default().id(n)
+    }
+
+    /// Sets the group name.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, ArgGroup};
+    /// ArgGroup::default().name("config")
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn id<S: Into<&'help str>>(mut self, n: S) -> Self {
+        self.name = n.into();
+        self.id = Id::from(self.name);
+        self
+    }
+
+    /// Deprecated, replaced with [`ArgGroup::id`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `ArgGroup::id`")
+    )]
+    pub fn name<S: Into<&'help str>>(self, n: S) -> Self {
+        self.id(n)
+    }
+
+    /// Adds an [argument] to this group by name
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgGroup};
+    /// let m = Command::new("myprog")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("color")
+    ///         .short('c'))
+    ///     .group(ArgGroup::new("req_flags")
+    ///         .arg("flag")
+    ///         .arg("color"))
+    ///     .get_matches_from(vec!["myprog", "-f"]);
+    /// // maybe we don't know which of the two flags was used...
+    /// assert!(m.contains_id("req_flags"));
+    /// // but we can also check individually if needed
+    /// assert!(m.contains_id("flag"));
+    /// ```
+    /// [argument]: crate::Arg
+    #[must_use]
+    pub fn arg<T: Key>(mut self, arg_id: T) -> Self {
+        self.args.push(arg_id.into());
+        self
+    }
+
+    /// Adds multiple [arguments] to this group by name
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgGroup};
+    /// let m = Command::new("myprog")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("color")
+    ///         .short('c'))
+    ///     .group(ArgGroup::new("req_flags")
+    ///         .args(&["flag", "color"]))
+    ///     .get_matches_from(vec!["myprog", "-f"]);
+    /// // maybe we don't know which of the two flags was used...
+    /// assert!(m.contains_id("req_flags"));
+    /// // but we can also check individually if needed
+    /// assert!(m.contains_id("flag"));
+    /// ```
+    /// [arguments]: crate::Arg
+    #[must_use]
+    pub fn args<T: Key>(mut self, ns: &[T]) -> Self {
+        for n in ns {
+            self = self.arg(n);
+        }
+        self
+    }
+
+    /// Allows more than one of the [`Arg`]s in this group to be used. (Default: `false`)
+    ///
+    /// # Examples
+    ///
+    /// Notice in this example we use *both* the `-f` and `-c` flags which are both part of the
+    /// group
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgGroup};
+    /// let m = Command::new("myprog")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("color")
+    ///         .short('c'))
+    ///     .group(ArgGroup::new("req_flags")
+    ///         .args(&["flag", "color"])
+    ///         .multiple(true))
+    ///     .get_matches_from(vec!["myprog", "-f", "-c"]);
+    /// // maybe we don't know which of the two flags was used...
+    /// assert!(m.contains_id("req_flags"));
+    /// ```
+    /// In this next example, we show the default behavior (i.e. `multiple(false)) which will throw
+    /// an error if more than one of the args in the group was used.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgGroup, ErrorKind};
+    /// let result = Command::new("myprog")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("color")
+    ///         .short('c'))
+    ///     .group(ArgGroup::new("req_flags")
+    ///         .args(&["flag", "color"]))
+    ///     .try_get_matches_from(vec!["myprog", "-f", "-c"]);
+    /// // Because we used both args in the group it's an error
+    /// assert!(result.is_err());
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), ErrorKind::ArgumentConflict);
+    /// ```
+    ///
+    /// [`Arg`]: crate::Arg
+    #[inline]
+    #[must_use]
+    pub fn multiple(mut self, yes: bool) -> Self {
+        self.multiple = yes;
+        self
+    }
+
+    /// Require an argument from the group to be present when parsing.
+    ///
+    /// This is unless conflicting with another argument.  A required group will be displayed in
+    /// the usage string of the application in the format `<arg|arg2|arg3>`.
+    ///
+    /// **NOTE:** This setting only applies to the current [`Command`] / [`Subcommand`]s, and not
+    /// globally.
+    ///
+    /// **NOTE:** By default, [`ArgGroup::multiple`] is set to `false` which when combined with
+    /// `ArgGroup::required(true)` states, "One and *only one* arg must be used from this group.
+    /// Use of more than one arg is an error." Vice setting `ArgGroup::multiple(true)` which
+    /// states, '*At least* one arg from this group must be used. Using multiple is OK."
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgGroup, ErrorKind};
+    /// let result = Command::new("myprog")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("color")
+    ///         .short('c'))
+    ///     .group(ArgGroup::new("req_flags")
+    ///         .args(&["flag", "color"])
+    ///         .required(true))
+    ///     .try_get_matches_from(vec!["myprog"]);
+    /// // Because we didn't use any of the args in the group, it's an error
+    /// assert!(result.is_err());
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    ///
+    /// [`Subcommand`]: crate::Subcommand
+    /// [`ArgGroup::multiple`]: ArgGroup::multiple()
+    /// [`Command`]: crate::Command
+    #[inline]
+    #[must_use]
+    pub fn required(mut self, yes: bool) -> Self {
+        self.required = yes;
+        self
+    }
+
+    /// Specify an argument or group that must be present when this group is.
+    ///
+    /// This is not to be confused with a [required group]. Requirement rules function just like
+    /// [argument requirement rules], you can name other arguments or groups that must be present
+    /// when any one of the arguments from this group is used.
+    ///
+    /// **NOTE:** The name provided may be an argument or group name
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgGroup, ErrorKind};
+    /// let result = Command::new("myprog")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("color")
+    ///         .short('c'))
+    ///     .arg(Arg::new("debug")
+    ///         .short('d'))
+    ///     .group(ArgGroup::new("req_flags")
+    ///         .args(&["flag", "color"])
+    ///         .requires("debug"))
+    ///     .try_get_matches_from(vec!["myprog", "-c"]);
+    /// // because we used an arg from the group, and the group requires "-d" to be used, it's an
+    /// // error
+    /// assert!(result.is_err());
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [required group]: ArgGroup::required()
+    /// [argument requirement rules]: crate::Arg::requires()
+    #[must_use]
+    pub fn requires<T: Key>(mut self, id: T) -> Self {
+        self.requires.push(id.into());
+        self
+    }
+
+    /// Specify arguments or groups that must be present when this group is.
+    ///
+    /// This is not to be confused with a [required group]. Requirement rules function just like
+    /// [argument requirement rules], you can name other arguments or groups that must be present
+    /// when one of the arguments from this group is used.
+    ///
+    /// **NOTE:** The names provided may be an argument or group name
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgGroup, ErrorKind};
+    /// let result = Command::new("myprog")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("color")
+    ///         .short('c'))
+    ///     .arg(Arg::new("debug")
+    ///         .short('d'))
+    ///     .arg(Arg::new("verb")
+    ///         .short('v'))
+    ///     .group(ArgGroup::new("req_flags")
+    ///         .args(&["flag", "color"])
+    ///         .requires_all(&["debug", "verb"]))
+    ///     .try_get_matches_from(vec!["myprog", "-c", "-d"]);
+    /// // because we used an arg from the group, and the group requires "-d" and "-v" to be used,
+    /// // yet we only used "-d" it's an error
+    /// assert!(result.is_err());
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    /// [required group]: ArgGroup::required()
+    /// [argument requirement rules]: crate::Arg::requires_all()
+    #[must_use]
+    pub fn requires_all(mut self, ns: &[&'help str]) -> Self {
+        for n in ns {
+            self = self.requires(n);
+        }
+        self
+    }
+
+    /// Specify an argument or group that must **not** be present when this group is.
+    ///
+    /// Exclusion (aka conflict) rules function just like [argument exclusion rules], you can name
+    /// other arguments or groups that must *not* be present when one of the arguments from this
+    /// group are used.
+    ///
+    /// **NOTE:** The name provided may be an argument, or group name
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgGroup, ErrorKind};
+    /// let result = Command::new("myprog")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("color")
+    ///         .short('c'))
+    ///     .arg(Arg::new("debug")
+    ///         .short('d'))
+    ///     .group(ArgGroup::new("req_flags")
+    ///         .args(&["flag", "color"])
+    ///         .conflicts_with("debug"))
+    ///     .try_get_matches_from(vec!["myprog", "-c", "-d"]);
+    /// // because we used an arg from the group, and the group conflicts with "-d", it's an error
+    /// assert!(result.is_err());
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), ErrorKind::ArgumentConflict);
+    /// ```
+    /// [argument exclusion rules]: crate::Arg::conflicts_with()
+    #[must_use]
+    pub fn conflicts_with<T: Key>(mut self, id: T) -> Self {
+        self.conflicts.push(id.into());
+        self
+    }
+
+    /// Specify arguments or groups that must **not** be present when this group is.
+    ///
+    /// Exclusion rules function just like [argument exclusion rules], you can name other arguments
+    /// or groups that must *not* be present when one of the arguments from this group are used.
+    ///
+    /// **NOTE:** The names provided may be an argument, or group name
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgGroup, ErrorKind};
+    /// let result = Command::new("myprog")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("color")
+    ///         .short('c'))
+    ///     .arg(Arg::new("debug")
+    ///         .short('d'))
+    ///     .arg(Arg::new("verb")
+    ///         .short('v'))
+    ///     .group(ArgGroup::new("req_flags")
+    ///         .args(&["flag", "color"])
+    ///         .conflicts_with_all(&["debug", "verb"]))
+    ///     .try_get_matches_from(vec!["myprog", "-c", "-v"]);
+    /// // because we used an arg from the group, and the group conflicts with either "-v" or "-d"
+    /// // it's an error
+    /// assert!(result.is_err());
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), ErrorKind::ArgumentConflict);
+    /// ```
+    ///
+    /// [argument exclusion rules]: crate::Arg::conflicts_with_all()
+    #[must_use]
+    pub fn conflicts_with_all(mut self, ns: &[&'help str]) -> Self {
+        for n in ns {
+            self = self.conflicts_with(n);
+        }
+        self
+    }
+
+    /// Deprecated, replaced with [`ArgGroup::new`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `ArgGroup::new`")
+    )]
+    #[doc(hidden)]
+    pub fn with_name<S: Into<&'help str>>(n: S) -> Self {
+        Self::new(n)
+    }
+
+    /// Deprecated in [Issue #3087](https://github.com/clap-rs/clap/issues/3087), maybe [`clap::Parser`][crate::Parser] would fit your use case?
+    #[cfg(feature = "yaml")]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Maybe clap::Parser would fit your use case? (Issue #3087)"
+        )
+    )]
+    #[doc(hidden)]
+    pub fn from_yaml(yaml: &'help Yaml) -> Self {
+        Self::from(yaml)
+    }
+}
+
+impl<'help> From<&'_ ArgGroup<'help>> for ArgGroup<'help> {
+    fn from(g: &ArgGroup<'help>) -> Self {
+        ArgGroup {
+            id: g.id.clone(),
+            name: g.name,
+            required: g.required,
+            args: g.args.clone(),
+            requires: g.requires.clone(),
+            conflicts: g.conflicts.clone(),
+            multiple: g.multiple,
+        }
+    }
+}
+
+/// Deprecated in [Issue #3087](https://github.com/clap-rs/clap/issues/3087), maybe [`clap::Parser`][crate::Parser] would fit your use case?
+#[cfg(feature = "yaml")]
+impl<'help> From<&'help Yaml> for ArgGroup<'help> {
+    /// Deprecated in [Issue #3087](https://github.com/clap-rs/clap/issues/3087), maybe [`clap::Parser`][crate::Parser] would fit your use case?
+    fn from(y: &'help Yaml) -> Self {
+        let b = y.as_hash().expect("ArgGroup::from::<Yaml> expects a table");
+        // We WANT this to panic on error...so expect() is good.
+        let mut a = ArgGroup::default();
+        let group_settings = if b.len() == 1 {
+            let name_yaml = b.keys().next().expect("failed to get name");
+            let name_str = name_yaml
+                .as_str()
+                .expect("failed to convert arg YAML name to str");
+            a.name = name_str;
+            a.id = Id::from(&a.name);
+            b.get(name_yaml)
+                .expect("failed to get name_str")
+                .as_hash()
+                .expect("failed to convert to a hash")
+        } else {
+            b
+        };
+
+        for (k, v) in group_settings {
+            a = match k.as_str().unwrap() {
+                "required" => a.required(v.as_bool().unwrap()),
+                "multiple" => a.multiple(v.as_bool().unwrap()),
+                "args" => yaml_vec_or_str!(a, v, arg),
+                "arg" => {
+                    if let Some(ys) = v.as_str() {
+                        a = a.arg(ys);
+                    }
+                    a
+                }
+                "requires" => yaml_vec_or_str!(a, v, requires),
+                "conflicts_with" => yaml_vec_or_str!(a, v, conflicts_with),
+                "name" => {
+                    if let Some(ys) = v.as_str() {
+                        a = a.id(ys);
+                    }
+                    a
+                }
+                s => panic!(
+                    "Unknown ArgGroup setting '{}' in YAML file for \
+                     ArgGroup '{}'",
+                    s, a.name
+                ),
+            }
+        }
+
+        a
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::ArgGroup;
+    #[cfg(feature = "yaml")]
+    use yaml_rust::YamlLoader;
+
+    #[test]
+    fn groups() {
+        let g = ArgGroup::new("test")
+            .arg("a1")
+            .arg("a4")
+            .args(&["a2", "a3"])
+            .required(true)
+            .conflicts_with("c1")
+            .conflicts_with_all(&["c2", "c3"])
+            .conflicts_with("c4")
+            .requires("r1")
+            .requires_all(&["r2", "r3"])
+            .requires("r4");
+
+        let args = vec!["a1".into(), "a4".into(), "a2".into(), "a3".into()];
+        let reqs = vec!["r1".into(), "r2".into(), "r3".into(), "r4".into()];
+        let confs = vec!["c1".into(), "c2".into(), "c3".into(), "c4".into()];
+
+        assert_eq!(g.args, args);
+        assert_eq!(g.requires, reqs);
+        assert_eq!(g.conflicts, confs);
+    }
+
+    #[test]
+    fn test_from() {
+        let g = ArgGroup::new("test")
+            .arg("a1")
+            .arg("a4")
+            .args(&["a2", "a3"])
+            .required(true)
+            .conflicts_with("c1")
+            .conflicts_with_all(&["c2", "c3"])
+            .conflicts_with("c4")
+            .requires("r1")
+            .requires_all(&["r2", "r3"])
+            .requires("r4");
+
+        let args = vec!["a1".into(), "a4".into(), "a2".into(), "a3".into()];
+        let reqs = vec!["r1".into(), "r2".into(), "r3".into(), "r4".into()];
+        let confs = vec!["c1".into(), "c2".into(), "c3".into(), "c4".into()];
+
+        let g2 = ArgGroup::from(&g);
+        assert_eq!(g2.args, args);
+        assert_eq!(g2.requires, reqs);
+        assert_eq!(g2.conflicts, confs);
+    }
+
+    #[cfg(feature = "yaml")]
+    #[test]
+    fn test_yaml() {
+        let g_yaml = "name: test
+args:
+- a1
+- a4
+- a2
+- a3
+conflicts_with:
+- c1
+- c2
+- c3
+- c4
+requires:
+- r1
+- r2
+- r3
+- r4";
+        let yaml = &YamlLoader::load_from_str(g_yaml).expect("failed to load YAML file")[0];
+        let g = ArgGroup::from(yaml);
+        let args = vec!["a1".into(), "a4".into(), "a2".into(), "a3".into()];
+        let reqs = vec!["r1".into(), "r2".into(), "r3".into(), "r4".into()];
+        let confs = vec!["c1".into(), "c2".into(), "c3".into(), "c4".into()];
+        assert_eq!(g.args, args);
+        assert_eq!(g.requires, reqs);
+        assert_eq!(g.conflicts, confs);
+    }
+
+    // This test will *fail to compile* if ArgGroup is not Send + Sync
+    #[test]
+    fn arg_group_send_sync() {
+        fn foo<T: Send + Sync>(_: T) {}
+        foo(ArgGroup::new("test"))
+    }
+}
+
+impl Clone for ArgGroup<'_> {
+    fn clone(&self) -> Self {
+        ArgGroup {
+            id: self.id.clone(),
+            name: self.name,
+            required: self.required,
+            args: self.args.clone(),
+            requires: self.requires.clone(),
+            conflicts: self.conflicts.clone(),
+            multiple: self.multiple,
+        }
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/arg_predicate.rs b/vendor/clap-3.2.20/src/builder/arg_predicate.rs
new file mode 100644
index 000000000..58eb5494c
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/arg_predicate.rs
@@ -0,0 +1,14 @@
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub(crate) enum ArgPredicate<'help> {
+    IsPresent,
+    Equals(&'help std::ffi::OsStr),
+}
+
+impl<'help> From<Option<&'help std::ffi::OsStr>> for ArgPredicate<'help> {
+    fn from(other: Option<&'help std::ffi::OsStr>) -> Self {
+        match other {
+            Some(other) => Self::Equals(other),
+            None => Self::IsPresent,
+        }
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/arg_settings.rs b/vendor/clap-3.2.20/src/builder/arg_settings.rs
new file mode 100644
index 000000000..ecc064caa
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/arg_settings.rs
@@ -0,0 +1,456 @@
+#![allow(deprecated)]
+
+// Std
+use std::ops::BitOr;
+#[cfg(feature = "yaml")]
+use std::str::FromStr;
+
+// Third party
+use bitflags::bitflags;
+
+#[allow(unused)]
+use crate::Arg;
+
+#[doc(hidden)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct ArgFlags(Flags);
+
+impl Default for ArgFlags {
+    fn default() -> Self {
+        Self::empty()
+    }
+}
+
+/// Various settings that apply to arguments and may be set, unset, and checked via getter/setter
+/// methods [`Arg::setting`], [`Arg::unset_setting`], and [`Arg::is_set`]. This is what the
+/// [`Arg`] methods which accept a `bool` use internally.
+///
+/// [`Arg`]: crate::Arg
+/// [`Arg::setting`]: crate::Arg::setting()
+/// [`Arg::unset_setting`]: crate::Arg::unset_setting()
+/// [`Arg::is_set`]: crate::Arg::is_set()
+#[derive(Debug, PartialEq, Copy, Clone)]
+#[non_exhaustive]
+pub enum ArgSettings {
+    /// Deprecated, replaced with [`Arg::required`] and [`Arg::is_required_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::required` and `Arg::is_required_set`"
+        )
+    )]
+    Required,
+    /// Deprecated, replaced with [`Arg::multiple_values`] and [`Arg::is_multiple_values_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::multiple_values` and `Arg::`is_multiple_values_set`"
+        )
+    )]
+    MultipleValues,
+    /// Deprecated, replaced with [`Arg::action`] ([Issue #3772](https://github.com/clap-rs/clap/issues/3772))
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Arg::action` (Issue #3772)")
+    )]
+    MultipleOccurrences,
+    /// Deprecated, see [`ArgSettings::MultipleOccurrences`] (most likely what you want) and
+    /// [`ArgSettings::MultipleValues`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Split into `Arg::multiple_occurrences` (most likely what you want)  and `Arg::multiple_values`"
+        )
+    )]
+    #[doc(hidden)]
+    Multiple,
+    /// Deprecated, replaced with [`Arg::value_parser(NonEmptyStringValueParser::new())`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::value_parser(NonEmptyStringValueParser::new())`"
+        )
+    )]
+    ForbidEmptyValues,
+    /// Deprecated, replaced with [`Arg::global`] and [`Arg::is_global_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::global` and `Arg::is_global_set`"
+        )
+    )]
+    Global,
+    /// Deprecated, replaced with [`Arg::hide`] and [`Arg::is_hide_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::hide` and `Arg::is_hide_set`"
+        )
+    )]
+    Hidden,
+    /// Deprecated, replaced with [`Arg::takes_value`] and [`Arg::is_takes_value_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::takes_value` and `Arg::is_takes_value_set`"
+        )
+    )]
+    TakesValue,
+    /// Deprecated, replaced with [`Arg::use_value_delimiter`] and
+    /// [`Arg::is_use_value_delimiter_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::use_value_delimiter` and `Arg::is_use_value_delimiter_set`"
+        )
+    )]
+    UseValueDelimiter,
+    /// Deprecated, replaced with [`Arg::next_line_help`] and [`Arg::is_next_line_help_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::next_line_help` and `Arg::is_next_line_help_set`"
+        )
+    )]
+    NextLineHelp,
+    /// Deprecated, replaced with [`Arg::require_value_delimiter`] and
+    /// [`Arg::is_require_value_delimiter_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::require_value_delimiter` and `Arg::is_require_value_delimiter_set`"
+        )
+    )]
+    RequireDelimiter,
+    /// Deprecated, replaced with [`Arg::hide_possible_values`] and
+    /// [`Arg::is_hide_possible_values_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::hide_possible_values` and `Arg::is_hide_possible_values_set`"
+        )
+    )]
+    HidePossibleValues,
+    /// Deprecated, replaced with [`Arg::allow_hyphen_values`] and
+    /// [`Arg::is_allow_hyphen_values_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::allow_hyphen_values` and `Arg::is_allow_hyphen_values_set`"
+        )
+    )]
+    AllowHyphenValues,
+    /// Deprecated, replaced with [`Arg::allow_hyphen_values`] and
+    /// [`Arg::is_allow_hyphen_values_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `Arg::allow_hyphen_values` and `Arg::is_allow_hyphen_values_set`"
+        )
+    )]
+    #[doc(hidden)]
+    AllowLeadingHyphen,
+    /// Deprecated, replaced with [`Arg::require_equals`] and [`Arg::is_require_equals_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::require_equals` and `Arg::is_require_equals_set`"
+        )
+    )]
+    RequireEquals,
+    /// Deprecated, replaced with [`Arg::last`] and [`Arg::is_last_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::last` and `Arg::is_last_set`"
+        )
+    )]
+    Last,
+    /// Deprecated, replaced with [`Arg::hide_default_value`] and [`Arg::is_hide_default_value_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::hide_default_value` and `Arg::is_hide_default_value_set`"
+        )
+    )]
+    HideDefaultValue,
+    /// Deprecated, replaced with [`Arg::ignore_case`] and [`Arg::is_ignore_case_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::ignore_case` and `Arg::is_ignore_case_set`"
+        )
+    )]
+    IgnoreCase,
+    /// Deprecated, replaced with [`Arg::ignore_case`] and [`Arg::is_ignore_case_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `Arg::ignore_case` and `Arg::is_ignore_case_set`"
+        )
+    )]
+    #[doc(hidden)]
+    CaseInsensitive,
+    /// Deprecated, replaced with [`Arg::hide_env`] and [`Arg::is_hide_env_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::hide_env` and `Arg::is_hide_env_set`"
+        )
+    )]
+    #[cfg(feature = "env")]
+    HideEnv,
+    /// Deprecated, replaced with [`Arg::hide_env_values`] and [`Arg::is_hide_env_values_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::hide_env_values` and `Arg::is_hide_env_values_set`"
+        )
+    )]
+    #[cfg(feature = "env")]
+    HideEnvValues,
+    /// Deprecated, replaced with [`Arg::hide_short_help`] and [`Arg::is_hide_short_help_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::hide_short_help` and `Arg::is_hide_short_help_set`"
+        )
+    )]
+    HiddenShortHelp,
+    /// Deprecated, replaced with [`Arg::hide_long_help`] and [`Arg::is_hide_long_help_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::hide_long_help` and `Arg::is_hide_long_help_set`"
+        )
+    )]
+    HiddenLongHelp,
+    /// Deprecated, replaced with [`Arg::allow_invalid_utf8`] and [`Arg::is_allow_invalid_utf8_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::allow_invalid_utf8` and `Arg::is_allow_invalid_utf8_set`"
+        )
+    )]
+    AllowInvalidUtf8,
+    /// Deprecated, replaced with [`Arg::exclusive`] and [`Arg::is_exclusive_set`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `Arg::exclusive` and `Arg::is_exclusive_set`"
+        )
+    )]
+    Exclusive,
+}
+
+bitflags! {
+    struct Flags: u32 {
+        const REQUIRED         = 1;
+        const MULTIPLE_OCC     = 1 << 1;
+        const NO_EMPTY_VALS    = 1 << 2;
+        const GLOBAL           = 1 << 3;
+        const HIDDEN           = 1 << 4;
+        const TAKES_VAL        = 1 << 5;
+        const USE_DELIM        = 1 << 6;
+        const NEXT_LINE_HELP   = 1 << 7;
+        const REQ_DELIM        = 1 << 9;
+        const DELIM_NOT_SET    = 1 << 10;
+        const HIDE_POS_VALS    = 1 << 11;
+        const ALLOW_TAC_VALS   = 1 << 12;
+        const REQUIRE_EQUALS   = 1 << 13;
+        const LAST             = 1 << 14;
+        const HIDE_DEFAULT_VAL = 1 << 15;
+        const CASE_INSENSITIVE = 1 << 16;
+        #[cfg(feature = "env")]
+        const HIDE_ENV_VALS    = 1 << 17;
+        const HIDDEN_SHORT_H   = 1 << 18;
+        const HIDDEN_LONG_H    = 1 << 19;
+        const MULTIPLE_VALS    = 1 << 20;
+        const MULTIPLE         = Self::MULTIPLE_OCC.bits | Self::MULTIPLE_VALS.bits;
+        #[cfg(feature = "env")]
+        const HIDE_ENV         = 1 << 21;
+        const UTF8_NONE        = 1 << 22;
+        const EXCLUSIVE        = 1 << 23;
+        const NO_OP            = 0;
+    }
+}
+
+impl_settings! { ArgSettings, ArgFlags,
+    Required => Flags::REQUIRED,
+    MultipleOccurrences => Flags::MULTIPLE_OCC,
+    MultipleValues => Flags::MULTIPLE_VALS,
+    Multiple => Flags::MULTIPLE,
+    ForbidEmptyValues => Flags::NO_EMPTY_VALS,
+    Global => Flags::GLOBAL,
+    Hidden => Flags::HIDDEN,
+    TakesValue => Flags::TAKES_VAL,
+    UseValueDelimiter => Flags::USE_DELIM,
+    NextLineHelp => Flags::NEXT_LINE_HELP,
+    RequireDelimiter => Flags::REQ_DELIM,
+    HidePossibleValues => Flags::HIDE_POS_VALS,
+    AllowHyphenValues => Flags::ALLOW_TAC_VALS,
+    AllowLeadingHyphen => Flags::ALLOW_TAC_VALS,
+    RequireEquals => Flags::REQUIRE_EQUALS,
+    Last => Flags::LAST,
+    IgnoreCase => Flags::CASE_INSENSITIVE,
+    CaseInsensitive => Flags::CASE_INSENSITIVE,
+    #[cfg(feature = "env")]
+    HideEnv => Flags::HIDE_ENV,
+    #[cfg(feature = "env")]
+    HideEnvValues => Flags::HIDE_ENV_VALS,
+    HideDefaultValue => Flags::HIDE_DEFAULT_VAL,
+    HiddenShortHelp => Flags::HIDDEN_SHORT_H,
+    HiddenLongHelp => Flags::HIDDEN_LONG_H,
+    AllowInvalidUtf8 => Flags::UTF8_NONE,
+    Exclusive => Flags::EXCLUSIVE
+}
+
+/// Deprecated in [Issue #3087](https://github.com/clap-rs/clap/issues/3087), maybe [`clap::Parser`][crate::Parser] would fit your use case?
+#[cfg(feature = "yaml")]
+impl FromStr for ArgSettings {
+    type Err = String;
+    fn from_str(s: &str) -> Result<Self, <Self as FromStr>::Err> {
+        #[allow(deprecated)]
+        #[allow(unreachable_patterns)]
+        match &*s.to_ascii_lowercase() {
+            "required" => Ok(ArgSettings::Required),
+            "multipleoccurrences" => Ok(ArgSettings::MultipleOccurrences),
+            "multiplevalues" => Ok(ArgSettings::MultipleValues),
+            "multiple" => Ok(ArgSettings::Multiple),
+            "forbidemptyvalues" => Ok(ArgSettings::ForbidEmptyValues),
+            "global" => Ok(ArgSettings::Global),
+            "hidden" => Ok(ArgSettings::Hidden),
+            "takesvalue" => Ok(ArgSettings::TakesValue),
+            "usevaluedelimiter" => Ok(ArgSettings::UseValueDelimiter),
+            "nextlinehelp" => Ok(ArgSettings::NextLineHelp),
+            "requiredelimiter" => Ok(ArgSettings::RequireDelimiter),
+            "hidepossiblevalues" => Ok(ArgSettings::HidePossibleValues),
+            "allowhyphenvalues" => Ok(ArgSettings::AllowHyphenValues),
+            "allowleadinghypyhen" => Ok(ArgSettings::AllowLeadingHyphen),
+            "requireequals" => Ok(ArgSettings::RequireEquals),
+            "last" => Ok(ArgSettings::Last),
+            "ignorecase" => Ok(ArgSettings::IgnoreCase),
+            "caseinsensitive" => Ok(ArgSettings::CaseInsensitive),
+            #[cfg(feature = "env")]
+            "hideenv" => Ok(ArgSettings::HideEnv),
+            #[cfg(feature = "env")]
+            "hideenvvalues" => Ok(ArgSettings::HideEnvValues),
+            "hidedefaultvalue" => Ok(ArgSettings::HideDefaultValue),
+            "hiddenshorthelp" => Ok(ArgSettings::HiddenShortHelp),
+            "hiddenlonghelp" => Ok(ArgSettings::HiddenLongHelp),
+            "allowinvalidutf8" => Ok(ArgSettings::AllowInvalidUtf8),
+            "exclusive" => Ok(ArgSettings::Exclusive),
+            _ => Err(format!("unknown AppSetting: `{}`", s)),
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    #[test]
+    #[cfg(feature = "yaml")]
+    fn arg_settings_fromstr() {
+        use super::ArgSettings;
+
+        assert_eq!(
+            "allowhyphenvalues".parse::<ArgSettings>().unwrap(),
+            ArgSettings::AllowHyphenValues
+        );
+        assert_eq!(
+            "forbidemptyvalues".parse::<ArgSettings>().unwrap(),
+            ArgSettings::ForbidEmptyValues
+        );
+        assert_eq!(
+            "hidepossiblevalues".parse::<ArgSettings>().unwrap(),
+            ArgSettings::HidePossibleValues
+        );
+        assert_eq!(
+            "hidden".parse::<ArgSettings>().unwrap(),
+            ArgSettings::Hidden
+        );
+        assert_eq!(
+            "nextlinehelp".parse::<ArgSettings>().unwrap(),
+            ArgSettings::NextLineHelp
+        );
+        assert_eq!(
+            "requiredelimiter".parse::<ArgSettings>().unwrap(),
+            ArgSettings::RequireDelimiter
+        );
+        assert_eq!(
+            "required".parse::<ArgSettings>().unwrap(),
+            ArgSettings::Required
+        );
+        assert_eq!(
+            "takesvalue".parse::<ArgSettings>().unwrap(),
+            ArgSettings::TakesValue
+        );
+        assert_eq!(
+            "usevaluedelimiter".parse::<ArgSettings>().unwrap(),
+            ArgSettings::UseValueDelimiter
+        );
+        assert_eq!(
+            "requireequals".parse::<ArgSettings>().unwrap(),
+            ArgSettings::RequireEquals
+        );
+        assert_eq!("last".parse::<ArgSettings>().unwrap(), ArgSettings::Last);
+        assert_eq!(
+            "hidedefaultvalue".parse::<ArgSettings>().unwrap(),
+            ArgSettings::HideDefaultValue
+        );
+        assert_eq!(
+            "ignorecase".parse::<ArgSettings>().unwrap(),
+            ArgSettings::IgnoreCase
+        );
+        #[cfg(feature = "env")]
+        assert_eq!(
+            "hideenv".parse::<ArgSettings>().unwrap(),
+            ArgSettings::HideEnv
+        );
+        #[cfg(feature = "env")]
+        assert_eq!(
+            "hideenvvalues".parse::<ArgSettings>().unwrap(),
+            ArgSettings::HideEnvValues
+        );
+        assert_eq!(
+            "hiddenshorthelp".parse::<ArgSettings>().unwrap(),
+            ArgSettings::HiddenShortHelp
+        );
+        assert_eq!(
+            "hiddenlonghelp".parse::<ArgSettings>().unwrap(),
+            ArgSettings::HiddenLongHelp
+        );
+        assert_eq!(
+            "allowinvalidutf8".parse::<ArgSettings>().unwrap(),
+            ArgSettings::AllowInvalidUtf8
+        );
+        assert_eq!(
+            "exclusive".parse::<ArgSettings>().unwrap(),
+            ArgSettings::Exclusive
+        );
+        assert!("hahahaha".parse::<ArgSettings>().is_err());
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/command.rs b/vendor/clap-3.2.20/src/builder/command.rs
new file mode 100644
index 000000000..de59ad8cd
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/command.rs
@@ -0,0 +1,5189 @@
+#![allow(deprecated)]
+
+// Std
+use std::collections::HashMap;
+use std::env;
+use std::ffi::OsString;
+use std::fmt;
+use std::io;
+use std::ops::Index;
+use std::path::Path;
+
+// Third Party
+#[cfg(feature = "yaml")]
+use yaml_rust::Yaml;
+
+// Internal
+use crate::builder::app_settings::{AppFlags, AppSettings};
+use crate::builder::arg_settings::ArgSettings;
+use crate::builder::{arg::ArgProvider, Arg, ArgGroup, ArgPredicate};
+use crate::error::ErrorKind;
+use crate::error::Result as ClapResult;
+use crate::mkeymap::MKeyMap;
+use crate::output::fmt::Stream;
+use crate::output::{fmt::Colorizer, Help, HelpWriter, Usage};
+use crate::parser::{ArgMatcher, ArgMatches, Parser};
+use crate::util::ChildGraph;
+use crate::util::{color::ColorChoice, Id, Key};
+use crate::PossibleValue;
+use crate::{Error, INTERNAL_ERROR_MSG};
+
+#[cfg(debug_assertions)]
+use crate::builder::debug_asserts::assert_app;
+
+/// Build a command-line interface.
+///
+/// This includes defining arguments, subcommands, parser behavior, and help output.
+/// Once all configuration is complete,
+/// the [`Command::get_matches`] family of methods starts the runtime-parsing
+/// process. These methods then return information about the user supplied
+/// arguments (or lack thereof).
+///
+/// When deriving a [`Parser`][crate::Parser], you can use
+/// [`CommandFactory::command`][crate::CommandFactory::command] to access the
+/// `Command`.
+///
+/// - [Basic API][crate::App#basic-api]
+/// - [Application-wide Settings][crate::App#application-wide-settings]
+/// - [Command-specific Settings][crate::App#command-specific-settings]
+/// - [Subcommand-specific Settings][crate::App#subcommand-specific-settings]
+/// - [Reflection][crate::App#reflection]
+///
+/// # Examples
+///
+/// ```no_run
+/// # use clap::{Command, Arg};
+/// let m = Command::new("My Program")
+///     .author("Me, me@mail.com")
+///     .version("1.0.2")
+///     .about("Explains in brief what the program does")
+///     .arg(
+///         Arg::new("in_file")
+///     )
+///     .after_help("Longer explanation to appear after the options when \
+///                  displaying the help information from --help or -h")
+///     .get_matches();
+///
+/// // Your program logic starts here...
+/// ```
+/// [`App::get_matches`]: Command::get_matches()
+pub type Command<'help> = App<'help>;
+
+/// Deprecated, replaced with [`Command`]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.1.0", note = "Replaced with `Command`")
+)]
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct App<'help> {
+    id: Id,
+    name: String,
+    long_flag: Option<&'help str>,
+    short_flag: Option<char>,
+    display_name: Option<String>,
+    bin_name: Option<String>,
+    author: Option<&'help str>,
+    version: Option<&'help str>,
+    long_version: Option<&'help str>,
+    about: Option<&'help str>,
+    long_about: Option<&'help str>,
+    before_help: Option<&'help str>,
+    before_long_help: Option<&'help str>,
+    after_help: Option<&'help str>,
+    after_long_help: Option<&'help str>,
+    aliases: Vec<(&'help str, bool)>,           // (name, visible)
+    short_flag_aliases: Vec<(char, bool)>,      // (name, visible)
+    long_flag_aliases: Vec<(&'help str, bool)>, // (name, visible)
+    usage_str: Option<&'help str>,
+    usage_name: Option<String>,
+    help_str: Option<&'help str>,
+    disp_ord: Option<usize>,
+    term_w: Option<usize>,
+    max_w: Option<usize>,
+    template: Option<&'help str>,
+    settings: AppFlags,
+    g_settings: AppFlags,
+    args: MKeyMap<'help>,
+    subcommands: Vec<App<'help>>,
+    replacers: HashMap<&'help str, &'help [&'help str]>,
+    groups: Vec<ArgGroup<'help>>,
+    current_help_heading: Option<&'help str>,
+    current_disp_ord: Option<usize>,
+    subcommand_value_name: Option<&'help str>,
+    subcommand_heading: Option<&'help str>,
+}
+
+/// # Basic API
+impl<'help> App<'help> {
+    /// Creates a new instance of an `Command`.
+    ///
+    /// It is common, but not required, to use binary name as the `name`. This
+    /// name will only be displayed to the user when they request to print
+    /// version or help and usage information.
+    ///
+    /// See also [`command!`](crate::command!) and [`crate_name!`](crate::crate_name!).
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("My Program")
+    /// # ;
+    /// ```
+    pub fn new<S: Into<String>>(name: S) -> Self {
+        /// The actual implementation of `new`, non-generic to save code size.
+        ///
+        /// If we don't do this rustc will unnecessarily generate multiple versions
+        /// of this code.
+        fn new_inner<'help>(name: String) -> App<'help> {
+            App {
+                id: Id::from(&*name),
+                name,
+                ..Default::default()
+            }
+            .arg(
+                Arg::new("help")
+                    .long("help")
+                    .help("Print help information")
+                    .global(true)
+                    .generated(),
+            )
+            .arg(
+                Arg::new("version")
+                    .long("version")
+                    .help("Print version information")
+                    .global(true)
+                    .generated(),
+            )
+        }
+
+        new_inner(name.into())
+    }
+
+    /// Adds an [argument] to the list of valid possibilities.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, arg, Arg};
+    /// Command::new("myprog")
+    ///     // Adding a single "flag" argument with a short and help text, using Arg::new()
+    ///     .arg(
+    ///         Arg::new("debug")
+    ///            .short('d')
+    ///            .help("turns on debugging mode")
+    ///     )
+    ///     // Adding a single "option" argument with a short, a long, and help text using the less
+    ///     // verbose Arg::from()
+    ///     .arg(
+    ///         arg!(-c --config <CONFIG> "Optionally sets a config file to use")
+    ///     )
+    /// # ;
+    /// ```
+    /// [argument]: Arg
+    #[must_use]
+    pub fn arg<A: Into<Arg<'help>>>(mut self, a: A) -> Self {
+        let mut arg = a.into();
+        if let Some(current_disp_ord) = self.current_disp_ord.as_mut() {
+            if !arg.is_positional() && arg.provider != ArgProvider::Generated {
+                let current = *current_disp_ord;
+                arg.disp_ord.set_implicit(current);
+                *current_disp_ord = current + 1;
+            }
+        }
+
+        arg.help_heading.get_or_insert(self.current_help_heading);
+        self.args.push(arg);
+        self
+    }
+
+    /// Adds multiple [arguments] to the list of valid possibilities.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, arg, Arg};
+    /// Command::new("myprog")
+    ///     .args(&[
+    ///         arg!("[debug] -d 'turns on debugging info'"),
+    ///         Arg::new("input").help("the input file to use")
+    ///     ])
+    /// # ;
+    /// ```
+    /// [arguments]: Arg
+    #[must_use]
+    pub fn args<I, T>(mut self, args: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<Arg<'help>>,
+    {
+        let args = args.into_iter();
+        let (lower, _) = args.size_hint();
+        self.args.reserve(lower);
+
+        for arg in args {
+            self = self.arg(arg);
+        }
+        self
+    }
+
+    /// Allows one to mutate an [`Arg`] after it's been added to a [`Command`].
+    ///
+    /// This can be useful for modifying the auto-generated help or version arguments.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    ///
+    /// let mut cmd = Command::new("foo")
+    ///     .arg(Arg::new("bar")
+    ///         .short('b'))
+    ///     .mut_arg("bar", |a| a.short('B'));
+    ///
+    /// let res = cmd.try_get_matches_from_mut(vec!["foo", "-b"]);
+    ///
+    /// // Since we changed `bar`'s short to "B" this should err as there
+    /// // is no `-b` anymore, only `-B`
+    ///
+    /// assert!(res.is_err());
+    ///
+    /// let res = cmd.try_get_matches_from_mut(vec!["foo", "-B"]);
+    /// assert!(res.is_ok());
+    /// ```
+    #[must_use]
+    pub fn mut_arg<T, F>(mut self, arg_id: T, f: F) -> Self
+    where
+        F: FnOnce(Arg<'help>) -> Arg<'help>,
+        T: Key + Into<&'help str>,
+    {
+        let arg_id: &str = arg_id.into();
+        let id = Id::from(arg_id);
+
+        let mut a = self.args.remove_by_name(&id).unwrap_or_else(|| Arg {
+            id,
+            name: arg_id,
+            ..Arg::default()
+        });
+
+        if a.provider == ArgProvider::Generated {
+            a.provider = ArgProvider::GeneratedMutated;
+        }
+
+        self.args.push(f(a));
+        self
+    }
+
+    /// Allows one to mutate a [`Command`] after it's been added as a subcommand.
+    ///
+    /// This can be useful for modifying auto-generated arguments of nested subcommands with
+    /// [`Command::mut_arg`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    ///
+    /// let mut cmd = Command::new("foo")
+    ///         .subcommand(Command::new("bar"))
+    ///         .mut_subcommand("bar", |subcmd| subcmd.disable_help_flag(true));
+    ///
+    /// let res = cmd.try_get_matches_from_mut(vec!["foo", "bar", "--help"]);
+    ///
+    /// // Since we disabled the help flag on the "bar" subcommand, this should err.
+    ///
+    /// assert!(res.is_err());
+    ///
+    /// let res = cmd.try_get_matches_from_mut(vec!["foo", "bar"]);
+    /// assert!(res.is_ok());
+    /// ```
+    #[must_use]
+    pub fn mut_subcommand<'a, T, F>(mut self, subcmd_id: T, f: F) -> Self
+    where
+        F: FnOnce(App<'help>) -> App<'help>,
+        T: Into<&'a str>,
+    {
+        let subcmd_id: &str = subcmd_id.into();
+        let id = Id::from(subcmd_id);
+
+        let pos = self.subcommands.iter().position(|s| s.id == id);
+
+        let subcmd = if let Some(idx) = pos {
+            self.subcommands.remove(idx)
+        } else {
+            App::new(subcmd_id)
+        };
+
+        self.subcommands.push(f(subcmd));
+        self
+    }
+
+    /// Adds an [`ArgGroup`] to the application.
+    ///
+    /// [`ArgGroup`]s are a family of related arguments.
+    /// By placing them in a logical group, you can build easier requirement and exclusion rules.
+    ///
+    /// Example use cases:
+    /// - Make an entire [`ArgGroup`] required, meaning that one (and *only*
+    ///   one) argument from that group must be present at runtime.
+    /// - Name an [`ArgGroup`] as a conflict to another argument.
+    ///   Meaning any of the arguments that belong to that group will cause a failure if present with
+    ///   the conflicting argument.
+    /// - Ensure exclusion between arguments.
+    /// - Extract a value from a group instead of determining exactly which argument was used.
+    ///
+    /// # Examples
+    ///
+    /// The following example demonstrates using an [`ArgGroup`] to ensure that one, and only one,
+    /// of the arguments from the specified group is present at runtime.
+    ///
+    /// ```no_run
+    /// # use clap::{Command, arg, ArgGroup};
+    /// Command::new("cmd")
+    ///     .arg(arg!("--set-ver [ver] 'set the version manually'"))
+    ///     .arg(arg!("--major 'auto increase major'"))
+    ///     .arg(arg!("--minor 'auto increase minor'"))
+    ///     .arg(arg!("--patch 'auto increase patch'"))
+    ///     .group(ArgGroup::new("vers")
+    ///          .args(&["set-ver", "major", "minor","patch"])
+    ///          .required(true))
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn group<G: Into<ArgGroup<'help>>>(mut self, group: G) -> Self {
+        self.groups.push(group.into());
+        self
+    }
+
+    /// Adds multiple [`ArgGroup`]s to the [`Command`] at once.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, arg, ArgGroup};
+    /// Command::new("cmd")
+    ///     .arg(arg!("--set-ver [ver] 'set the version manually'"))
+    ///     .arg(arg!("--major         'auto increase major'"))
+    ///     .arg(arg!("--minor         'auto increase minor'"))
+    ///     .arg(arg!("--patch         'auto increase patch'"))
+    ///     .arg(arg!("-c [FILE]       'a config file'"))
+    ///     .arg(arg!("-i [IFACE]      'an interface'"))
+    ///     .groups(&[
+    ///         ArgGroup::new("vers")
+    ///             .args(&["set-ver", "major", "minor","patch"])
+    ///             .required(true),
+    ///         ArgGroup::new("input")
+    ///             .args(&["c", "i"])
+    ///     ])
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn groups<I, T>(mut self, groups: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<ArgGroup<'help>>,
+    {
+        for g in groups.into_iter() {
+            self = self.group(g.into());
+        }
+        self
+    }
+
+    /// Adds a subcommand to the list of valid possibilities.
+    ///
+    /// Subcommands are effectively sub-[`Command`]s, because they can contain their own arguments,
+    /// subcommands, version, usage, etc. They also function just like [`Command`]s, in that they get
+    /// their own auto generated help, version, and usage.
+    ///
+    /// A subcommand's [`Command::name`] will be used for:
+    /// - The argument the user passes in
+    /// - Programmatically looking up the subcommand
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, arg};
+    /// Command::new("myprog")
+    ///     .subcommand(Command::new("config")
+    ///         .about("Controls configuration features")
+    ///         .arg(arg!("<config> 'Required configuration file to use'")))
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn subcommand<S: Into<App<'help>>>(mut self, subcmd: S) -> Self {
+        self.subcommands.push(subcmd.into());
+        self
+    }
+
+    /// Adds multiple subcommands to the list of valid possibilities.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, };
+    /// # Command::new("myprog")
+    /// .subcommands( vec![
+    ///        Command::new("config").about("Controls configuration functionality")
+    ///                                 .arg(Arg::new("config_file")),
+    ///        Command::new("debug").about("Controls debug functionality")])
+    /// # ;
+    /// ```
+    /// [`IntoIterator`]: std::iter::IntoIterator
+    #[must_use]
+    pub fn subcommands<I, T>(mut self, subcmds: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<App<'help>>,
+    {
+        for subcmd in subcmds.into_iter() {
+            self.subcommands.push(subcmd.into());
+        }
+        self
+    }
+
+    /// Catch problems earlier in the development cycle.
+    ///
+    /// Most error states are handled as asserts under the assumption they are programming mistake
+    /// and not something to handle at runtime.  Rather than relying on tests (manual or automated)
+    /// that exhaustively test your CLI to ensure the asserts are evaluated, this will run those
+    /// asserts in a way convenient for running as a test.
+    ///
+    /// **Note::** This will not help with asserts in [`ArgMatches`], those will need exhaustive
+    /// testing of your CLI.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// fn cmd() -> Command<'static> {
+    ///     Command::new("foo")
+    ///         .arg(
+    ///             Arg::new("bar").short('b').action(ArgAction::SetTrue)
+    ///         )
+    /// }
+    ///
+    /// #[test]
+    /// fn verify_app() {
+    ///     cmd().debug_assert();
+    /// }
+    ///
+    /// fn main() {
+    ///     let m = cmd().get_matches_from(vec!["foo", "-b"]);
+    ///     println!("{}", *m.get_one::<bool>("bar").expect("defaulted by clap"));
+    /// }
+    /// ```
+    pub fn debug_assert(mut self) {
+        self._build_all();
+    }
+
+    /// Custom error message for post-parsing validation
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, ErrorKind};
+    /// let mut cmd = Command::new("myprog");
+    /// let err = cmd.error(ErrorKind::InvalidValue, "Some failure case");
+    /// ```
+    pub fn error(&mut self, kind: ErrorKind, message: impl std::fmt::Display) -> Error {
+        Error::raw(kind, message).format(self)
+    }
+
+    /// Parse [`env::args_os`], exiting on failure.
+    ///
+    /// # Panics
+    ///
+    /// If contradictory arguments or settings exist.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// let matches = Command::new("myprog")
+    ///     // Args and options go here...
+    ///     .get_matches();
+    /// ```
+    /// [`env::args_os`]: std::env::args_os()
+    /// [`App::try_get_matches_from_mut`]: Command::try_get_matches_from_mut()
+    #[inline]
+    pub fn get_matches(self) -> ArgMatches {
+        self.get_matches_from(&mut env::args_os())
+    }
+
+    /// Parse [`env::args_os`], exiting on failure.
+    ///
+    /// Like [`App::get_matches`] but doesn't consume the `Command`.
+    ///
+    /// # Panics
+    ///
+    /// If contradictory arguments or settings exist.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// let mut cmd = Command::new("myprog")
+    ///     // Args and options go here...
+    ///     ;
+    /// let matches = cmd.get_matches_mut();
+    /// ```
+    /// [`env::args_os`]: std::env::args_os()
+    /// [`App::get_matches`]: Command::get_matches()
+    pub fn get_matches_mut(&mut self) -> ArgMatches {
+        self.try_get_matches_from_mut(&mut env::args_os())
+            .unwrap_or_else(|e| e.exit())
+    }
+
+    /// Parse [`env::args_os`], returning a [`clap::Result`] on failure.
+    ///
+    /// **NOTE:** This method WILL NOT exit when `--help` or `--version` (or short versions) are
+    /// used. It will return a [`clap::Error`], where the [`kind`] is a
+    /// [`ErrorKind::DisplayHelp`] or [`ErrorKind::DisplayVersion`] respectively. You must call
+    /// [`Error::exit`] or perform a [`std::process::exit`].
+    ///
+    /// # Panics
+    ///
+    /// If contradictory arguments or settings exist.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// let matches = Command::new("myprog")
+    ///     // Args and options go here...
+    ///     .try_get_matches()
+    ///     .unwrap_or_else(|e| e.exit());
+    /// ```
+    /// [`env::args_os`]: std::env::args_os()
+    /// [`Error::exit`]: crate::Error::exit()
+    /// [`std::process::exit`]: std::process::exit()
+    /// [`clap::Result`]: Result
+    /// [`clap::Error`]: crate::Error
+    /// [`kind`]: crate::Error
+    /// [`ErrorKind::DisplayHelp`]: crate::ErrorKind::DisplayHelp
+    /// [`ErrorKind::DisplayVersion`]: crate::ErrorKind::DisplayVersion
+    #[inline]
+    pub fn try_get_matches(self) -> ClapResult<ArgMatches> {
+        // Start the parsing
+        self.try_get_matches_from(&mut env::args_os())
+    }
+
+    /// Parse the specified arguments, exiting on failure.
+    ///
+    /// **NOTE:** The first argument will be parsed as the binary name unless
+    /// [`Command::no_binary_name`] is used.
+    ///
+    /// # Panics
+    ///
+    /// If contradictory arguments or settings exist.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// let arg_vec = vec!["my_prog", "some", "args", "to", "parse"];
+    ///
+    /// let matches = Command::new("myprog")
+    ///     // Args and options go here...
+    ///     .get_matches_from(arg_vec);
+    /// ```
+    /// [`App::get_matches`]: Command::get_matches()
+    /// [`clap::Result`]: Result
+    /// [`Vec`]: std::vec::Vec
+    pub fn get_matches_from<I, T>(mut self, itr: I) -> ArgMatches
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        self.try_get_matches_from_mut(itr).unwrap_or_else(|e| {
+            drop(self);
+            e.exit()
+        })
+    }
+
+    /// Parse the specified arguments, returning a [`clap::Result`] on failure.
+    ///
+    /// **NOTE:** This method WILL NOT exit when `--help` or `--version` (or short versions) are
+    /// used. It will return a [`clap::Error`], where the [`kind`] is a [`ErrorKind::DisplayHelp`]
+    /// or [`ErrorKind::DisplayVersion`] respectively. You must call [`Error::exit`] or
+    /// perform a [`std::process::exit`] yourself.
+    ///
+    /// **NOTE:** The first argument will be parsed as the binary name unless
+    /// [`Command::no_binary_name`] is used.
+    ///
+    /// # Panics
+    ///
+    /// If contradictory arguments or settings exist.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// let arg_vec = vec!["my_prog", "some", "args", "to", "parse"];
+    ///
+    /// let matches = Command::new("myprog")
+    ///     // Args and options go here...
+    ///     .try_get_matches_from(arg_vec)
+    ///     .unwrap_or_else(|e| e.exit());
+    /// ```
+    /// [`App::get_matches_from`]: Command::get_matches_from()
+    /// [`App::try_get_matches`]: Command::try_get_matches()
+    /// [`Error::exit`]: crate::Error::exit()
+    /// [`std::process::exit`]: std::process::exit()
+    /// [`clap::Error`]: crate::Error
+    /// [`Error::exit`]: crate::Error::exit()
+    /// [`kind`]: crate::Error
+    /// [`ErrorKind::DisplayHelp`]: crate::ErrorKind::DisplayHelp
+    /// [`ErrorKind::DisplayVersion`]: crate::ErrorKind::DisplayVersion
+    /// [`clap::Result`]: Result
+    pub fn try_get_matches_from<I, T>(mut self, itr: I) -> ClapResult<ArgMatches>
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        self.try_get_matches_from_mut(itr)
+    }
+
+    /// Parse the specified arguments, returning a [`clap::Result`] on failure.
+    ///
+    /// Like [`App::try_get_matches_from`] but doesn't consume the `Command`.
+    ///
+    /// **NOTE:** This method WILL NOT exit when `--help` or `--version` (or short versions) are
+    /// used. It will return a [`clap::Error`], where the [`kind`] is a [`ErrorKind::DisplayHelp`]
+    /// or [`ErrorKind::DisplayVersion`] respectively. You must call [`Error::exit`] or
+    /// perform a [`std::process::exit`] yourself.
+    ///
+    /// **NOTE:** The first argument will be parsed as the binary name unless
+    /// [`Command::no_binary_name`] is used.
+    ///
+    /// # Panics
+    ///
+    /// If contradictory arguments or settings exist.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// let arg_vec = vec!["my_prog", "some", "args", "to", "parse"];
+    ///
+    /// let mut cmd = Command::new("myprog");
+    ///     // Args and options go here...
+    /// let matches = cmd.try_get_matches_from_mut(arg_vec)
+    ///     .unwrap_or_else(|e| e.exit());
+    /// ```
+    /// [`App::try_get_matches_from`]: Command::try_get_matches_from()
+    /// [`clap::Result`]: Result
+    /// [`clap::Error`]: crate::Error
+    /// [`kind`]: crate::Error
+    pub fn try_get_matches_from_mut<I, T>(&mut self, itr: I) -> ClapResult<ArgMatches>
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        let mut raw_args = clap_lex::RawArgs::new(itr.into_iter());
+        let mut cursor = raw_args.cursor();
+
+        if self.settings.is_set(AppSettings::Multicall) {
+            if let Some(argv0) = raw_args.next_os(&mut cursor) {
+                let argv0 = Path::new(&argv0);
+                if let Some(command) = argv0.file_stem().and_then(|f| f.to_str()) {
+                    // Stop borrowing command so we can get another mut ref to it.
+                    let command = command.to_owned();
+                    debug!(
+                        "Command::try_get_matches_from_mut: Parsed command {} from argv",
+                        command
+                    );
+
+                    debug!("Command::try_get_matches_from_mut: Reinserting command into arguments so subcommand parser matches it");
+                    raw_args.insert(&cursor, &[&command]);
+                    debug!("Command::try_get_matches_from_mut: Clearing name and bin_name so that displayed command name starts with applet name");
+                    self.name.clear();
+                    self.bin_name = None;
+                    return self._do_parse(&mut raw_args, cursor);
+                }
+            }
+        };
+
+        // Get the name of the program (argument 1 of env::args()) and determine the
+        // actual file
+        // that was used to execute the program. This is because a program called
+        // ./target/release/my_prog -a
+        // will have two arguments, './target/release/my_prog', '-a' but we don't want
+        // to display
+        // the full path when displaying help messages and such
+        if !self.settings.is_set(AppSettings::NoBinaryName) {
+            if let Some(name) = raw_args.next_os(&mut cursor) {
+                let p = Path::new(name);
+
+                if let Some(f) = p.file_name() {
+                    if let Some(s) = f.to_str() {
+                        if self.bin_name.is_none() {
+                            self.bin_name = Some(s.to_owned());
+                        }
+                    }
+                }
+            }
+        }
+
+        self._do_parse(&mut raw_args, cursor)
+    }
+
+    /// Prints the short help message (`-h`) to [`io::stdout()`].
+    ///
+    /// See also [`Command::print_long_help`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// let mut cmd = Command::new("myprog");
+    /// cmd.print_help();
+    /// ```
+    /// [`io::stdout()`]: std::io::stdout()
+    pub fn print_help(&mut self) -> io::Result<()> {
+        self._build_self();
+        let color = self.color_help();
+
+        let mut c = Colorizer::new(Stream::Stdout, color);
+        let usage = Usage::new(self);
+        Help::new(HelpWriter::Buffer(&mut c), self, &usage, false).write_help()?;
+        c.print()
+    }
+
+    /// Prints the long help message (`--help`) to [`io::stdout()`].
+    ///
+    /// See also [`Command::print_help`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// let mut cmd = Command::new("myprog");
+    /// cmd.print_long_help();
+    /// ```
+    /// [`io::stdout()`]: std::io::stdout()
+    /// [`BufWriter`]: std::io::BufWriter
+    /// [`-h` (short)]: Arg::help()
+    /// [`--help` (long)]: Arg::long_help()
+    pub fn print_long_help(&mut self) -> io::Result<()> {
+        self._build_self();
+        let color = self.color_help();
+
+        let mut c = Colorizer::new(Stream::Stdout, color);
+        let usage = Usage::new(self);
+        Help::new(HelpWriter::Buffer(&mut c), self, &usage, true).write_help()?;
+        c.print()
+    }
+
+    /// Writes the short help message (`-h`) to a [`io::Write`] object.
+    ///
+    /// See also [`Command::write_long_help`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// use std::io;
+    /// let mut cmd = Command::new("myprog");
+    /// let mut out = io::stdout();
+    /// cmd.write_help(&mut out).expect("failed to write to stdout");
+    /// ```
+    /// [`io::Write`]: std::io::Write
+    /// [`-h` (short)]: Arg::help()
+    /// [`--help` (long)]: Arg::long_help()
+    pub fn write_help<W: io::Write>(&mut self, w: &mut W) -> io::Result<()> {
+        self._build_self();
+
+        let usage = Usage::new(self);
+        Help::new(HelpWriter::Normal(w), self, &usage, false).write_help()?;
+        w.flush()
+    }
+
+    /// Writes the long help message (`--help`) to a [`io::Write`] object.
+    ///
+    /// See also [`Command::write_help`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// use std::io;
+    /// let mut cmd = Command::new("myprog");
+    /// let mut out = io::stdout();
+    /// cmd.write_long_help(&mut out).expect("failed to write to stdout");
+    /// ```
+    /// [`io::Write`]: std::io::Write
+    /// [`-h` (short)]: Arg::help()
+    /// [`--help` (long)]: Arg::long_help()
+    pub fn write_long_help<W: io::Write>(&mut self, w: &mut W) -> io::Result<()> {
+        self._build_self();
+
+        let usage = Usage::new(self);
+        Help::new(HelpWriter::Normal(w), self, &usage, true).write_help()?;
+        w.flush()
+    }
+
+    /// Version message rendered as if the user ran `-V`.
+    ///
+    /// See also [`Command::render_long_version`].
+    ///
+    /// ### Coloring
+    ///
+    /// This function does not try to color the message nor it inserts any [ANSI escape codes].
+    ///
+    /// ### Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// use std::io;
+    /// let cmd = Command::new("myprog");
+    /// println!("{}", cmd.render_version());
+    /// ```
+    /// [`io::Write`]: std::io::Write
+    /// [`-V` (short)]: Command::version()
+    /// [`--version` (long)]: Command::long_version()
+    /// [ANSI escape codes]: https://en.wikipedia.org/wiki/ANSI_escape_code
+    pub fn render_version(&self) -> String {
+        self._render_version(false)
+    }
+
+    /// Version message rendered as if the user ran `--version`.
+    ///
+    /// See also [`Command::render_version`].
+    ///
+    /// ### Coloring
+    ///
+    /// This function does not try to color the message nor it inserts any [ANSI escape codes].
+    ///
+    /// ### Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// use std::io;
+    /// let cmd = Command::new("myprog");
+    /// println!("{}", cmd.render_long_version());
+    /// ```
+    /// [`io::Write`]: std::io::Write
+    /// [`-V` (short)]: Command::version()
+    /// [`--version` (long)]: Command::long_version()
+    /// [ANSI escape codes]: https://en.wikipedia.org/wiki/ANSI_escape_code
+    pub fn render_long_version(&self) -> String {
+        self._render_version(true)
+    }
+
+    /// Usage statement
+    ///
+    /// ### Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// use std::io;
+    /// let mut cmd = Command::new("myprog");
+    /// println!("{}", cmd.render_usage());
+    /// ```
+    pub fn render_usage(&mut self) -> String {
+        // If there are global arguments, or settings we need to propagate them down to subcommands
+        // before parsing incase we run into a subcommand
+        self._build_self();
+
+        Usage::new(self).create_usage_with_title(&[])
+    }
+}
+
+/// # Application-wide Settings
+///
+/// These settings will apply to the top-level command and all subcommands, by default.  Some
+/// settings can be overridden in subcommands.
+impl<'help> App<'help> {
+    /// Specifies that the parser should not assume the first argument passed is the binary name.
+    ///
+    /// This is normally the case when using a "daemon" style mode.  For shells / REPLs, see
+    /// [`Command::multicall`][App::multicall].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, arg};
+    /// let m = Command::new("myprog")
+    ///     .no_binary_name(true)
+    ///     .arg(arg!(<cmd> ... "commands to run"))
+    ///     .get_matches_from(vec!["command", "set"]);
+    ///
+    /// let cmds: Vec<&str> = m.values_of("cmd").unwrap().collect();
+    /// assert_eq!(cmds, ["command", "set"]);
+    /// ```
+    /// [`try_get_matches_from_mut`]: crate::Command::try_get_matches_from_mut()
+    #[inline]
+    pub fn no_binary_name(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::NoBinaryName)
+        } else {
+            self.unset_global_setting(AppSettings::NoBinaryName)
+        }
+    }
+
+    /// Try not to fail on parse errors, like missing option values.
+    ///
+    /// **Note:** Make sure you apply it as `global_setting` if you want this setting
+    /// to be propagated to subcommands and sub-subcommands!
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, arg};
+    /// let cmd = Command::new("cmd")
+    ///   .ignore_errors(true)
+    ///   .arg(arg!(-c --config <FILE> "Sets a custom config file").required(false))
+    ///   .arg(arg!(-x --stuff <FILE> "Sets a custom stuff file").required(false))
+    ///   .arg(arg!(f: -f "Flag"));
+    ///
+    /// let r = cmd.try_get_matches_from(vec!["cmd", "-c", "file", "-f", "-x"]);
+    ///
+    /// assert!(r.is_ok(), "unexpected error: {:?}", r);
+    /// let m = r.unwrap();
+    /// assert_eq!(m.value_of("config"), Some("file"));
+    /// assert!(m.is_present("f"));
+    /// assert_eq!(m.value_of("stuff"), None);
+    /// ```
+    #[inline]
+    pub fn ignore_errors(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::IgnoreErrors)
+        } else {
+            self.unset_global_setting(AppSettings::IgnoreErrors)
+        }
+    }
+
+    /// Deprecated, replaced with [`ArgAction::Set`][super::ArgAction::Set]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `Arg::action(ArgAction::Set)`")
+    )]
+    pub fn args_override_self(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::AllArgsOverrideSelf)
+        } else {
+            self.unset_global_setting(AppSettings::AllArgsOverrideSelf)
+        }
+    }
+
+    /// Disables the automatic delimiting of values after `--` or when [`Command::trailing_var_arg`]
+    /// was used.
+    ///
+    /// **NOTE:** The same thing can be done manually by setting the final positional argument to
+    /// [`Arg::use_value_delimiter(false)`]. Using this setting is safer, because it's easier to locate
+    /// when making changes.
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .dont_delimit_trailing_values(true)
+    ///     .get_matches();
+    /// ```
+    ///
+    /// [`Arg::use_value_delimiter(false)`]: crate::Arg::use_value_delimiter()
+    #[inline]
+    pub fn dont_delimit_trailing_values(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::DontDelimitTrailingValues)
+        } else {
+            self.unset_global_setting(AppSettings::DontDelimitTrailingValues)
+        }
+    }
+
+    /// Sets when to color output.
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// **NOTE:** Default behaviour is [`ColorChoice::Auto`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, ColorChoice};
+    /// Command::new("myprog")
+    ///     .color(ColorChoice::Never)
+    ///     .get_matches();
+    /// ```
+    /// [`ColorChoice::Auto`]: crate::ColorChoice::Auto
+    #[cfg(feature = "color")]
+    #[inline]
+    #[must_use]
+    pub fn color(self, color: ColorChoice) -> Self {
+        #![allow(deprecated)]
+        let cmd = self
+            .unset_global_setting(AppSettings::ColorAuto)
+            .unset_global_setting(AppSettings::ColorAlways)
+            .unset_global_setting(AppSettings::ColorNever);
+        match color {
+            ColorChoice::Auto => cmd.global_setting(AppSettings::ColorAuto),
+            ColorChoice::Always => cmd.global_setting(AppSettings::ColorAlways),
+            ColorChoice::Never => cmd.global_setting(AppSettings::ColorNever),
+        }
+    }
+
+    /// Sets the terminal width at which to wrap help messages.
+    ///
+    /// Using `0` will ignore terminal widths and use source formatting.
+    ///
+    /// Defaults to current terminal width when `wrap_help` feature flag is enabled.  If the flag
+    /// is disabled or it cannot be determined, the default is 100.
+    ///
+    /// **NOTE:** This setting applies globally and *not* on a per-command basis.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .term_width(80)
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn term_width(mut self, width: usize) -> Self {
+        self.term_w = Some(width);
+        self
+    }
+
+    /// Sets the maximum terminal width at which to wrap help messages.
+    ///
+    /// This only applies when setting the current terminal width.  See [`Command::term_width`] for
+    /// more details.
+    ///
+    /// Using `0` will ignore terminal widths and use source formatting.
+    ///
+    /// **NOTE:** This setting applies globally and *not* on a per-command basis.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .max_term_width(100)
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn max_term_width(mut self, w: usize) -> Self {
+        self.max_w = Some(w);
+        self
+    }
+
+    /// Disables `-V` and `--version` flag.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, ErrorKind};
+    /// let res = Command::new("myprog")
+    ///     .disable_version_flag(true)
+    ///     .try_get_matches_from(vec![
+    ///         "myprog", "-V"
+    ///     ]);
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::UnknownArgument);
+    /// ```
+    #[inline]
+    pub fn disable_version_flag(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::DisableVersionFlag)
+        } else {
+            self.unset_global_setting(AppSettings::DisableVersionFlag)
+        }
+    }
+
+    /// Specifies to use the version of the current command for all [`subcommands`].
+    ///
+    /// Defaults to `false`; subcommands have independent version strings from their parents.
+    ///
+    /// **Note:** Make sure you apply it as `global_setting` if you want this setting
+    /// to be propagated to subcommands and sub-subcommands!
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .version("v1.1")
+    ///     .propagate_version(true)
+    ///     .subcommand(Command::new("test"))
+    ///     .get_matches();
+    /// // running `$ myprog test --version` will display
+    /// // "myprog-test v1.1"
+    /// ```
+    ///
+    /// [`subcommands`]: crate::Command::subcommand()
+    #[inline]
+    pub fn propagate_version(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::PropagateVersion)
+        } else {
+            self.unset_global_setting(AppSettings::PropagateVersion)
+        }
+    }
+
+    /// Places the help string for all arguments and subcommands on the line after them.
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .next_line_help(true)
+    ///     .get_matches();
+    /// ```
+    #[inline]
+    pub fn next_line_help(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::NextLineHelp)
+        } else {
+            self.unset_global_setting(AppSettings::NextLineHelp)
+        }
+    }
+
+    /// Disables `-h` and `--help` flag.
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, ErrorKind};
+    /// let res = Command::new("myprog")
+    ///     .disable_help_flag(true)
+    ///     .try_get_matches_from(vec![
+    ///         "myprog", "-h"
+    ///     ]);
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::UnknownArgument);
+    /// ```
+    #[inline]
+    pub fn disable_help_flag(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::DisableHelpFlag)
+        } else {
+            self.unset_global_setting(AppSettings::DisableHelpFlag)
+        }
+    }
+
+    /// Disables the `help` [`subcommand`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, ErrorKind};
+    /// let res = Command::new("myprog")
+    ///     .disable_help_subcommand(true)
+    ///     // Normally, creating a subcommand causes a `help` subcommand to automatically
+    ///     // be generated as well
+    ///     .subcommand(Command::new("test"))
+    ///     .try_get_matches_from(vec![
+    ///         "myprog", "help"
+    ///     ]);
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::UnknownArgument);
+    /// ```
+    ///
+    /// [`subcommand`]: crate::Command::subcommand()
+    #[inline]
+    pub fn disable_help_subcommand(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::DisableHelpSubcommand)
+        } else {
+            self.unset_global_setting(AppSettings::DisableHelpSubcommand)
+        }
+    }
+
+    /// Disables colorized help messages.
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .disable_colored_help(true)
+    ///     .get_matches();
+    /// ```
+    #[inline]
+    pub fn disable_colored_help(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::DisableColoredHelp)
+        } else {
+            self.unset_global_setting(AppSettings::DisableColoredHelp)
+        }
+    }
+
+    /// Panic if help descriptions are omitted.
+    ///
+    /// **NOTE:** When deriving [`Parser`][crate::Parser], you could instead check this at
+    /// compile-time with `#![deny(missing_docs)]`
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .help_expected(true)
+    ///     .arg(
+    ///         Arg::new("foo").help("It does foo stuff")
+    ///         // As required via `help_expected`, a help message was supplied
+    ///      )
+    /// #    .get_matches();
+    /// ```
+    ///
+    /// # Panics
+    ///
+    /// ```rust,no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myapp")
+    ///     .help_expected(true)
+    ///     .arg(
+    ///         Arg::new("foo")
+    ///         // Someone forgot to put .about("...") here
+    ///         // Since the setting `help_expected` is activated, this will lead to
+    ///         // a panic (if you are in debug mode)
+    ///     )
+    /// #   .get_matches();
+    ///```
+    #[inline]
+    pub fn help_expected(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::HelpExpected)
+        } else {
+            self.unset_global_setting(AppSettings::HelpExpected)
+        }
+    }
+
+    /// Disables the automatic collapsing of positional args into `[ARGS]` inside the usage string.
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .dont_collapse_args_in_usage(true)
+    ///     .get_matches();
+    /// ```
+    #[inline]
+    pub fn dont_collapse_args_in_usage(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::DontCollapseArgsInUsage)
+        } else {
+            self.unset_global_setting(AppSettings::DontCollapseArgsInUsage)
+        }
+    }
+
+    /// Tells `clap` *not* to print possible values when displaying help information.
+    ///
+    /// This can be useful if there are many values, or they are explained elsewhere.
+    ///
+    /// To set this per argument, see
+    /// [`Arg::hide_possible_values`][crate::Arg::hide_possible_values].
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    #[inline]
+    pub fn hide_possible_values(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::HidePossibleValues)
+        } else {
+            self.unset_global_setting(AppSettings::HidePossibleValues)
+        }
+    }
+
+    /// Allow partial matches of long arguments or their [aliases].
+    ///
+    /// For example, to match an argument named `--test`, one could use `--t`, `--te`, `--tes`, and
+    /// `--test`.
+    ///
+    /// **NOTE:** The match *must not* be ambiguous at all in order to succeed. i.e. to match
+    /// `--te` to `--test` there could not also be another argument or alias `--temp` because both
+    /// start with `--te`
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// [aliases]: crate::Command::aliases()
+    #[inline]
+    pub fn infer_long_args(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::InferLongArgs)
+        } else {
+            self.unset_global_setting(AppSettings::InferLongArgs)
+        }
+    }
+
+    /// Allow partial matches of [subcommand] names and their [aliases].
+    ///
+    /// For example, to match a subcommand named `test`, one could use `t`, `te`, `tes`, and
+    /// `test`.
+    ///
+    /// **NOTE:** The match *must not* be ambiguous at all in order to succeed. i.e. to match `te`
+    /// to `test` there could not also be a subcommand or alias `temp` because both start with `te`
+    ///
+    /// **CAUTION:** This setting can interfere with [positional/free arguments], take care when
+    /// designing CLIs which allow inferred subcommands and have potential positional/free
+    /// arguments whose values could start with the same characters as subcommands. If this is the
+    /// case, it's recommended to use settings such as [`Command::args_conflicts_with_subcommands`] in
+    /// conjunction with this setting.
+    ///
+    /// **NOTE:** This choice is propagated to all child subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("prog")
+    ///     .infer_subcommands(true)
+    ///     .subcommand(Command::new("test"))
+    ///     .get_matches_from(vec![
+    ///         "prog", "te"
+    ///     ]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    ///
+    /// [subcommand]: crate::Command::subcommand()
+    /// [positional/free arguments]: crate::Arg::index()
+    /// [aliases]: crate::Command::aliases()
+    #[inline]
+    pub fn infer_subcommands(self, yes: bool) -> Self {
+        if yes {
+            self.global_setting(AppSettings::InferSubcommands)
+        } else {
+            self.unset_global_setting(AppSettings::InferSubcommands)
+        }
+    }
+}
+
+/// # Command-specific Settings
+///
+/// These apply only to the current command and are not inherited by subcommands.
+impl<'help> App<'help> {
+    /// (Re)Sets the program's name.
+    ///
+    /// See [`Command::new`] for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```ignore
+    /// # use clap::{Command, load_yaml};
+    /// let yaml = load_yaml!("cmd.yaml");
+    /// let cmd = Command::from(yaml)
+    ///     .name(crate_name!());
+    ///
+    /// // continued logic goes here, such as `cmd.get_matches()` etc.
+    /// ```
+    #[must_use]
+    pub fn name<S: Into<String>>(mut self, name: S) -> Self {
+        self.name = name.into();
+        self
+    }
+
+    /// Overrides the runtime-determined name of the binary for help and error messages.
+    ///
+    /// This should only be used when absolutely necessary, such as when the binary name for your
+    /// application is misleading, or perhaps *not* how the user should invoke your program.
+    ///
+    /// **Pro-tip:** When building things such as third party `cargo`
+    /// subcommands, this setting **should** be used!
+    ///
+    /// **NOTE:** This *does not* change or set the name of the binary file on
+    /// disk. It only changes what clap thinks the name is for the purposes of
+    /// error or help messages.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("My Program")
+    ///      .bin_name("my_binary")
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn bin_name<S: Into<String>>(mut self, name: S) -> Self {
+        self.bin_name = Some(name.into());
+        self
+    }
+
+    /// Overrides the runtime-determined display name of the program for help and error messages.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("My Program")
+    ///      .display_name("my_program")
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn display_name<S: Into<String>>(mut self, name: S) -> Self {
+        self.display_name = Some(name.into());
+        self
+    }
+
+    /// Sets the author(s) for the help message.
+    ///
+    /// **Pro-tip:** Use `clap`s convenience macro [`crate_authors!`] to
+    /// automatically set your application's author(s) to the same thing as your
+    /// crate at compile time.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///      .author("Me, me@mymain.com")
+    /// # ;
+    /// ```
+    /// [`crate_authors!`]: ./macro.crate_authors!.html
+    #[must_use]
+    pub fn author<S: Into<&'help str>>(mut self, author: S) -> Self {
+        self.author = Some(author.into());
+        self
+    }
+
+    /// Sets the program's description for the short help (`-h`).
+    ///
+    /// If [`Command::long_about`] is not specified, this message will be displayed for `--help`.
+    ///
+    /// **NOTE:** Only `Command::about` (short format) is used in completion
+    /// script generation in order to be concise.
+    ///
+    /// See also [`crate_description!`](crate::crate_description!).
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .about("Does really amazing things for great people")
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn about<O: Into<Option<&'help str>>>(mut self, about: O) -> Self {
+        self.about = about.into();
+        self
+    }
+
+    /// Sets the program's description for the long help (`--help`).
+    ///
+    /// If [`Command::about`] is not specified, this message will be displayed for `-h`.
+    ///
+    /// **NOTE:** Only [`Command::about`] (short format) is used in completion
+    /// script generation in order to be concise.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .long_about(
+    /// "Does really amazing things to great people. Now let's talk a little
+    ///  more in depth about how this subcommand really works. It may take about
+    ///  a few lines of text, but that's ok!")
+    /// # ;
+    /// ```
+    /// [`App::about`]: Command::about()
+    #[must_use]
+    pub fn long_about<O: Into<Option<&'help str>>>(mut self, long_about: O) -> Self {
+        self.long_about = long_about.into();
+        self
+    }
+
+    /// Free-form help text for after auto-generated short help (`-h`).
+    ///
+    /// This is often used to describe how to use the arguments, caveats to be noted, or license
+    /// and contact information.
+    ///
+    /// If [`Command::after_long_help`] is not specified, this message will be displayed for `--help`.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .after_help("Does really amazing things for great people... but be careful with -R!")
+    /// # ;
+    /// ```
+    ///
+    #[must_use]
+    pub fn after_help<S: Into<&'help str>>(mut self, help: S) -> Self {
+        self.after_help = Some(help.into());
+        self
+    }
+
+    /// Free-form help text for after auto-generated long help (`--help`).
+    ///
+    /// This is often used to describe how to use the arguments, caveats to be noted, or license
+    /// and contact information.
+    ///
+    /// If [`Command::after_help`] is not specified, this message will be displayed for `-h`.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .after_long_help("Does really amazing things to great people... but be careful with -R, \
+    ///                      like, for real, be careful with this!")
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn after_long_help<S: Into<&'help str>>(mut self, help: S) -> Self {
+        self.after_long_help = Some(help.into());
+        self
+    }
+
+    /// Free-form help text for before auto-generated short help (`-h`).
+    ///
+    /// This is often used for header, copyright, or license information.
+    ///
+    /// If [`Command::before_long_help`] is not specified, this message will be displayed for `--help`.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .before_help("Some info I'd like to appear before the help info")
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn before_help<S: Into<&'help str>>(mut self, help: S) -> Self {
+        self.before_help = Some(help.into());
+        self
+    }
+
+    /// Free-form help text for before auto-generated long help (`--help`).
+    ///
+    /// This is often used for header, copyright, or license information.
+    ///
+    /// If [`Command::before_help`] is not specified, this message will be displayed for `-h`.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .before_long_help("Some verbose and long info I'd like to appear before the help info")
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn before_long_help<S: Into<&'help str>>(mut self, help: S) -> Self {
+        self.before_long_help = Some(help.into());
+        self
+    }
+
+    /// Sets the version for the short version (`-V`) and help messages.
+    ///
+    /// If [`Command::long_version`] is not specified, this message will be displayed for `--version`.
+    ///
+    /// **Pro-tip:** Use `clap`s convenience macro [`crate_version!`] to
+    /// automatically set your application's version to the same thing as your
+    /// crate at compile time.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .version("v0.1.24")
+    /// # ;
+    /// ```
+    /// [`crate_version!`]: ./macro.crate_version!.html
+    #[must_use]
+    pub fn version<S: Into<&'help str>>(mut self, ver: S) -> Self {
+        self.version = Some(ver.into());
+        self
+    }
+
+    /// Sets the version for the long version (`--version`) and help messages.
+    ///
+    /// If [`Command::version`] is not specified, this message will be displayed for `-V`.
+    ///
+    /// **Pro-tip:** Use `clap`s convenience macro [`crate_version!`] to
+    /// automatically set your application's version to the same thing as your
+    /// crate at compile time.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .long_version(
+    /// "v0.1.24
+    ///  commit: abcdef89726d
+    ///  revision: 123
+    ///  release: 2
+    ///  binary: myprog")
+    /// # ;
+    /// ```
+    /// [`crate_version!`]: ./macro.crate_version!.html
+    #[must_use]
+    pub fn long_version<S: Into<&'help str>>(mut self, ver: S) -> Self {
+        self.long_version = Some(ver.into());
+        self
+    }
+
+    /// Overrides the `clap` generated usage string for help and error messages.
+    ///
+    /// **NOTE:** Using this setting disables `clap`s "context-aware" usage
+    /// strings. After this setting is set, this will be *the only* usage string
+    /// displayed to the user!
+    ///
+    /// **NOTE:** Multiple usage lines may be present in the usage argument, but
+    /// some rules need to be followed to ensure the usage lines are formatted
+    /// correctly by the default help formatter:
+    ///
+    /// - Do not indent the first usage line.
+    /// - Indent all subsequent usage lines with four spaces.
+    /// - The last line must not end with a newline.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .override_usage("myapp [-clDas] <some_file>")
+    /// # ;
+    /// ```
+    ///
+    /// Or for multiple usage lines:
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .override_usage(
+    ///         "myapp -X [-a] [-b] <file>\n    \
+    ///          myapp -Y [-c] <file1> <file2>\n    \
+    ///          myapp -Z [-d|-e]"
+    ///     )
+    /// # ;
+    /// ```
+    ///
+    /// [`ArgMatches::usage`]: ArgMatches::usage()
+    #[must_use]
+    pub fn override_usage<S: Into<&'help str>>(mut self, usage: S) -> Self {
+        self.usage_str = Some(usage.into());
+        self
+    }
+
+    /// Overrides the `clap` generated help message (both `-h` and `--help`).
+    ///
+    /// This should only be used when the auto-generated message does not suffice.
+    ///
+    /// **NOTE:** This **only** replaces the help message for the current
+    /// command, meaning if you are using subcommands, those help messages will
+    /// still be auto-generated unless you specify a [`Command::override_help`] for
+    /// them as well.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myapp")
+    ///     .override_help("myapp v1.0\n\
+    ///            Does awesome things\n\
+    ///            (C) me@mail.com\n\n\
+    ///
+    ///            USAGE: myapp <opts> <command>\n\n\
+    ///
+    ///            Options:\n\
+    ///            -h, --help       Display this message\n\
+    ///            -V, --version    Display version info\n\
+    ///            -s <stuff>       Do something with stuff\n\
+    ///            -v               Be verbose\n\n\
+    ///
+    ///            Commands:\n\
+    ///            help             Print this message\n\
+    ///            work             Do some work")
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn override_help<S: Into<&'help str>>(mut self, help: S) -> Self {
+        self.help_str = Some(help.into());
+        self
+    }
+
+    /// Sets the help template to be used, overriding the default format.
+    ///
+    /// **NOTE:** The template system is by design very simple. Therefore, the
+    /// tags have to be written in the lowercase and without spacing.
+    ///
+    /// Tags are given inside curly brackets.
+    ///
+    /// Valid tags are:
+    ///
+    ///   * `{name}`                - Display name for the (sub-)command.
+    ///   * `{bin}`                 - Binary name.
+    ///   * `{version}`             - Version number.
+    ///   * `{author}`              - Author information.
+    ///   * `{author-with-newline}` - Author followed by `\n`.
+    ///   * `{author-section}`      - Author preceded and followed by `\n`.
+    ///   * `{about}`               - General description (from [`Command::about`] or
+    ///                               [`Command::long_about`]).
+    ///   * `{about-with-newline}`  - About followed by `\n`.
+    ///   * `{about-section}`       - About preceded and followed by '\n'.
+    ///   * `{usage-heading}`       - Automatically generated usage heading.
+    ///   * `{usage}`               - Automatically generated or given usage string.
+    ///   * `{all-args}`            - Help for all arguments (options, flags, positional
+    ///                               arguments, and subcommands) including titles.
+    ///   * `{options}`             - Help for options.
+    ///   * `{positionals}`         - Help for positional arguments.
+    ///   * `{subcommands}`         - Help for subcommands.
+    ///   * `{after-help}`          - Help from [`App::after_help`] or [`Command::after_long_help`].
+    ///   * `{before-help}`         - Help from [`App::before_help`] or [`Command::before_long_help`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .version("1.0")
+    ///     .help_template("{bin} ({version}) - {usage}")
+    /// # ;
+    /// ```
+    /// [`App::about`]: Command::about()
+    /// [`App::long_about`]: Command::long_about()
+    /// [`App::after_help`]: Command::after_help()
+    /// [`App::after_long_help`]: Command::after_long_help()
+    /// [`App::before_help`]: Command::before_help()
+    /// [`App::before_long_help`]: Command::before_long_help()
+    #[must_use]
+    pub fn help_template<S: Into<&'help str>>(mut self, s: S) -> Self {
+        self.template = Some(s.into());
+        self
+    }
+
+    /// Apply a setting for the current command or subcommand.
+    ///
+    /// See [`Command::global_setting`] to apply a setting to this command and all subcommands.
+    ///
+    /// See [`AppSettings`] for a full list of possibilities and examples.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, AppSettings};
+    /// Command::new("myprog")
+    ///     .setting(AppSettings::SubcommandRequired)
+    ///     .setting(AppSettings::AllowLeadingHyphen)
+    /// # ;
+    /// ```
+    /// or
+    /// ```no_run
+    /// # use clap::{Command, AppSettings};
+    /// Command::new("myprog")
+    ///     .setting(AppSettings::SubcommandRequired | AppSettings::AllowLeadingHyphen)
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn setting<F>(mut self, setting: F) -> Self
+    where
+        F: Into<AppFlags>,
+    {
+        self.settings.insert(setting.into());
+        self
+    }
+
+    /// Remove a setting for the current command or subcommand.
+    ///
+    /// See [`AppSettings`] for a full list of possibilities and examples.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, AppSettings};
+    /// Command::new("myprog")
+    ///     .unset_setting(AppSettings::SubcommandRequired)
+    ///     .setting(AppSettings::AllowLeadingHyphen)
+    /// # ;
+    /// ```
+    /// or
+    /// ```no_run
+    /// # use clap::{Command, AppSettings};
+    /// Command::new("myprog")
+    ///     .unset_setting(AppSettings::SubcommandRequired | AppSettings::AllowLeadingHyphen)
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn unset_setting<F>(mut self, setting: F) -> Self
+    where
+        F: Into<AppFlags>,
+    {
+        self.settings.remove(setting.into());
+        self
+    }
+
+    /// Apply a setting for the current command and all subcommands.
+    ///
+    /// See [`Command::setting`] to apply a setting only to this command.
+    ///
+    /// See [`AppSettings`] for a full list of possibilities and examples.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, AppSettings};
+    /// Command::new("myprog")
+    ///     .global_setting(AppSettings::AllowNegativeNumbers)
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn global_setting(mut self, setting: AppSettings) -> Self {
+        self.settings.set(setting);
+        self.g_settings.set(setting);
+        self
+    }
+
+    /// Remove a setting and stop propagating down to subcommands.
+    ///
+    /// See [`AppSettings`] for a full list of possibilities and examples.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, AppSettings};
+    /// Command::new("myprog")
+    ///     .unset_global_setting(AppSettings::AllowNegativeNumbers)
+    /// # ;
+    /// ```
+    /// [global]: Command::global_setting()
+    #[inline]
+    #[must_use]
+    pub fn unset_global_setting(mut self, setting: AppSettings) -> Self {
+        self.settings.unset(setting);
+        self.g_settings.unset(setting);
+        self
+    }
+
+    /// Deprecated, replaced with [`Command::next_help_heading`]
+    #[inline]
+    #[must_use]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `App::next_help_heading`")
+    )]
+    pub fn help_heading<O>(self, heading: O) -> Self
+    where
+        O: Into<Option<&'help str>>,
+    {
+        self.next_help_heading(heading)
+    }
+
+    /// Set the default section heading for future args.
+    ///
+    /// This will be used for any arg that hasn't had [`Arg::help_heading`] called.
+    ///
+    /// This is useful if the default `OPTIONS` or `ARGS` headings are
+    /// not specific enough for one's use case.
+    ///
+    /// For subcommands, see [`Command::subcommand_help_heading`]
+    ///
+    /// [`App::arg`]: Command::arg()
+    /// [`Arg::help_heading`]: crate::Arg::help_heading()
+    #[inline]
+    #[must_use]
+    pub fn next_help_heading<O>(mut self, heading: O) -> Self
+    where
+        O: Into<Option<&'help str>>,
+    {
+        self.current_help_heading = heading.into();
+        self
+    }
+
+    /// Change the starting value for assigning future display orders for ags.
+    ///
+    /// This will be used for any arg that hasn't had [`Arg::display_order`] called.
+    #[inline]
+    #[must_use]
+    pub fn next_display_order(mut self, disp_ord: impl Into<Option<usize>>) -> Self {
+        self.current_disp_ord = disp_ord.into();
+        self
+    }
+
+    /// Replaces an argument or subcommand used on the CLI at runtime with other arguments or subcommands.
+    ///
+    /// **Note:** This is gated behind [`unstable-replace`](https://github.com/clap-rs/clap/issues/2836)
+    ///
+    /// When this method is used, `name` is removed from the CLI, and `target`
+    /// is inserted in its place. Parsing continues as if the user typed
+    /// `target` instead of `name`.
+    ///
+    /// This can be used to create "shortcuts" for subcommands, or if a
+    /// particular argument has the semantic meaning of several other specific
+    /// arguments and values.
+    ///
+    /// # Examples
+    ///
+    /// We'll start with the "subcommand short" example. In this example, let's
+    /// assume we have a program with a subcommand `module` which can be invoked
+    /// via `cmd module`. Now let's also assume `module` also has a subcommand
+    /// called `install` which can be invoked `cmd module install`. If for some
+    /// reason users needed to be able to reach `cmd module install` via the
+    /// short-hand `cmd install`, we'd have several options.
+    ///
+    /// We *could* create another sibling subcommand to `module` called
+    /// `install`, but then we would need to manage another subcommand and manually
+    /// dispatch to `cmd module install` handling code. This is error prone and
+    /// tedious.
+    ///
+    /// We could instead use [`Command::replace`] so that, when the user types `cmd
+    /// install`, `clap` will replace `install` with `module install` which will
+    /// end up getting parsed as if the user typed the entire incantation.
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// let m = Command::new("cmd")
+    ///     .subcommand(Command::new("module")
+    ///         .subcommand(Command::new("install")))
+    ///     .replace("install", &["module", "install"])
+    ///     .get_matches_from(vec!["cmd", "install"]);
+    ///
+    /// assert!(m.subcommand_matches("module").is_some());
+    /// assert!(m.subcommand_matches("module").unwrap().subcommand_matches("install").is_some());
+    /// ```
+    ///
+    /// Now let's show an argument example!
+    ///
+    /// Let's assume we have an application with two flags `--save-context` and
+    /// `--save-runtime`. But often users end up needing to do *both* at the
+    /// same time. We can add a third flag `--save-all` which semantically means
+    /// the same thing as `cmd --save-context --save-runtime`. To implement that,
+    /// we have several options.
+    ///
+    /// We could create this third argument and manually check if that argument
+    /// and in our own consumer code handle the fact that both `--save-context`
+    /// and `--save-runtime` *should* have been used. But again this is error
+    /// prone and tedious. If we had code relying on checking `--save-context`
+    /// and we forgot to update that code to *also* check `--save-all` it'd mean
+    /// an error!
+    ///
+    /// Luckily we can use [`Command::replace`] so that when the user types
+    /// `--save-all`, `clap` will replace that argument with `--save-context
+    /// --save-runtime`, and parsing will continue like normal. Now all our code
+    /// that was originally checking for things like `--save-context` doesn't
+    /// need to change!
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let m = Command::new("cmd")
+    ///     .arg(Arg::new("save-context")
+    ///         .long("save-context")
+    ///         .action(ArgAction::SetTrue))
+    ///     .arg(Arg::new("save-runtime")
+    ///         .long("save-runtime")
+    ///         .action(ArgAction::SetTrue))
+    ///     .replace("--save-all", &["--save-context", "--save-runtime"])
+    ///     .get_matches_from(vec!["cmd", "--save-all"]);
+    ///
+    /// assert!(*m.get_one::<bool>("save-context").expect("defaulted by clap"));
+    /// assert!(*m.get_one::<bool>("save-runtime").expect("defaulted by clap"));
+    /// ```
+    ///
+    /// This can also be used with options, for example if our application with
+    /// `--save-*` above also had a `--format=TYPE` option. Let's say it
+    /// accepted `txt` or `json` values. However, when `--save-all` is used,
+    /// only `--format=json` is allowed, or valid. We could change the example
+    /// above to enforce this:
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let m = Command::new("cmd")
+    ///     .arg(Arg::new("save-context")
+    ///         .long("save-context")
+    ///         .action(ArgAction::SetTrue))
+    ///     .arg(Arg::new("save-runtime")
+    ///         .long("save-runtime")
+    ///         .action(ArgAction::SetTrue))
+    ///     .arg(Arg::new("format")
+    ///         .long("format")
+    ///         .takes_value(true)
+    ///         .value_parser(["txt", "json"]))
+    ///     .replace("--save-all", &["--save-context", "--save-runtime", "--format=json"])
+    ///     .get_matches_from(vec!["cmd", "--save-all"]);
+    ///
+    /// assert!(*m.get_one::<bool>("save-context").expect("defaulted by clap"));
+    /// assert!(*m.get_one::<bool>("save-runtime").expect("defaulted by clap"));
+    /// assert_eq!(m.value_of("format"), Some("json"));
+    /// ```
+    ///
+    /// [`App::replace`]: Command::replace()
+    #[inline]
+    #[cfg(feature = "unstable-replace")]
+    #[must_use]
+    pub fn replace(mut self, name: &'help str, target: &'help [&'help str]) -> Self {
+        self.replacers.insert(name, target);
+        self
+    }
+
+    /// Exit gracefully if no arguments are present (e.g. `$ myprog`).
+    ///
+    /// **NOTE:** [`subcommands`] count as arguments
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command};
+    /// Command::new("myprog")
+    ///     .arg_required_else_help(true);
+    /// ```
+    ///
+    /// [`subcommands`]: crate::Command::subcommand()
+    /// [`Arg::default_value`]: crate::Arg::default_value()
+    #[inline]
+    pub fn arg_required_else_help(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::ArgRequiredElseHelp)
+        } else {
+            self.unset_setting(AppSettings::ArgRequiredElseHelp)
+        }
+    }
+
+    /// Specifies that leading hyphens are allowed in all argument *values* (e.g. `-10`).
+    ///
+    /// Otherwise they will be parsed as another flag or option.  See also
+    /// [`Command::allow_negative_numbers`].
+    ///
+    /// **NOTE:** Use this setting with caution as it silences certain circumstances which would
+    /// otherwise be an error (such as accidentally forgetting to specify a value for leading
+    /// option). It is preferred to set this on a per argument basis, via [`Arg::allow_hyphen_values`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Arg, Command};
+    /// // Imagine you needed to represent negative numbers as well, such as -10
+    /// let m = Command::new("nums")
+    ///     .allow_hyphen_values(true)
+    ///     .arg(Arg::new("neg"))
+    ///     .get_matches_from(vec![
+    ///         "nums", "-20"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("neg"), Some("-20"));
+    /// # ;
+    /// ```
+    /// [`Arg::allow_hyphen_values`]: crate::Arg::allow_hyphen_values()
+    #[inline]
+    pub fn allow_hyphen_values(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::AllowHyphenValues)
+        } else {
+            self.unset_setting(AppSettings::AllowHyphenValues)
+        }
+    }
+
+    /// Allows negative numbers to pass as values.
+    ///
+    /// This is similar to [`Command::allow_hyphen_values`] except that it only allows numbers,
+    /// all other undefined leading hyphens will fail to parse.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let res = Command::new("myprog")
+    ///     .allow_negative_numbers(true)
+    ///     .arg(Arg::new("num"))
+    ///     .try_get_matches_from(vec![
+    ///         "myprog", "-20"
+    ///     ]);
+    /// assert!(res.is_ok());
+    /// let m = res.unwrap();
+    /// assert_eq!(m.value_of("num").unwrap(), "-20");
+    /// ```
+    #[inline]
+    pub fn allow_negative_numbers(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::AllowNegativeNumbers)
+        } else {
+            self.unset_setting(AppSettings::AllowNegativeNumbers)
+        }
+    }
+
+    /// Specifies that the final positional argument is a "VarArg" and that `clap` should not
+    /// attempt to parse any further args.
+    ///
+    /// The values of the trailing positional argument will contain all args from itself on.
+    ///
+    /// **NOTE:** The final positional argument **must** have [`Arg::multiple_values(true)`] or the usage
+    /// string equivalent.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, arg};
+    /// let m = Command::new("myprog")
+    ///     .trailing_var_arg(true)
+    ///     .arg(arg!(<cmd> ... "commands to run"))
+    ///     .get_matches_from(vec!["myprog", "arg1", "-r", "val1"]);
+    ///
+    /// let trail: Vec<&str> = m.values_of("cmd").unwrap().collect();
+    /// assert_eq!(trail, ["arg1", "-r", "val1"]);
+    /// ```
+    /// [`Arg::multiple_values(true)`]: crate::Arg::multiple_values()
+    pub fn trailing_var_arg(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::TrailingVarArg)
+        } else {
+            self.unset_setting(AppSettings::TrailingVarArg)
+        }
+    }
+
+    /// Allows one to implement two styles of CLIs where positionals can be used out of order.
+    ///
+    /// The first example is a CLI where the second to last positional argument is optional, but
+    /// the final positional argument is required. Such as `$ prog [optional] <required>` where one
+    /// of the two following usages is allowed:
+    ///
+    /// * `$ prog [optional] <required>`
+    /// * `$ prog <required>`
+    ///
+    /// This would otherwise not be allowed. This is useful when `[optional]` has a default value.
+    ///
+    /// **Note:** when using this style of "missing positionals" the final positional *must* be
+    /// [required] if `--` will not be used to skip to the final positional argument.
+    ///
+    /// **Note:** This style also only allows a single positional argument to be "skipped" without
+    /// the use of `--`. To skip more than one, see the second example.
+    ///
+    /// The second example is when one wants to skip multiple optional positional arguments, and use
+    /// of the `--` operator is OK (but not required if all arguments will be specified anyways).
+    ///
+    /// For example, imagine a CLI which has three positional arguments `[foo] [bar] [baz]...` where
+    /// `baz` accepts multiple values (similar to man `ARGS...` style training arguments).
+    ///
+    /// With this setting the following invocations are posisble:
+    ///
+    /// * `$ prog foo bar baz1 baz2 baz3`
+    /// * `$ prog foo -- baz1 baz2 baz3`
+    /// * `$ prog -- baz1 baz2 baz3`
+    ///
+    /// # Examples
+    ///
+    /// Style number one from above:
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// // Assume there is an external subcommand named "subcmd"
+    /// let m = Command::new("myprog")
+    ///     .allow_missing_positional(true)
+    ///     .arg(Arg::new("arg1"))
+    ///     .arg(Arg::new("arg2")
+    ///         .required(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "other"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("arg1"), None);
+    /// assert_eq!(m.value_of("arg2"), Some("other"));
+    /// ```
+    ///
+    /// Now the same example, but using a default value for the first optional positional argument
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// // Assume there is an external subcommand named "subcmd"
+    /// let m = Command::new("myprog")
+    ///     .allow_missing_positional(true)
+    ///     .arg(Arg::new("arg1")
+    ///         .default_value("something"))
+    ///     .arg(Arg::new("arg2")
+    ///         .required(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "other"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("arg1"), Some("something"));
+    /// assert_eq!(m.value_of("arg2"), Some("other"));
+    /// ```
+    ///
+    /// Style number two from above:
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// // Assume there is an external subcommand named "subcmd"
+    /// let m = Command::new("myprog")
+    ///     .allow_missing_positional(true)
+    ///     .arg(Arg::new("foo"))
+    ///     .arg(Arg::new("bar"))
+    ///     .arg(Arg::new("baz").takes_value(true).multiple_values(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "foo", "bar", "baz1", "baz2", "baz3"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("foo"), Some("foo"));
+    /// assert_eq!(m.value_of("bar"), Some("bar"));
+    /// assert_eq!(m.values_of("baz").unwrap().collect::<Vec<_>>(), &["baz1", "baz2", "baz3"]);
+    /// ```
+    ///
+    /// Now nofice if we don't specify `foo` or `baz` but use the `--` operator.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// // Assume there is an external subcommand named "subcmd"
+    /// let m = Command::new("myprog")
+    ///     .allow_missing_positional(true)
+    ///     .arg(Arg::new("foo"))
+    ///     .arg(Arg::new("bar"))
+    ///     .arg(Arg::new("baz").takes_value(true).multiple_values(true))
+    ///     .get_matches_from(vec![
+    ///         "prog", "--", "baz1", "baz2", "baz3"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_of("foo"), None);
+    /// assert_eq!(m.value_of("bar"), None);
+    /// assert_eq!(m.values_of("baz").unwrap().collect::<Vec<_>>(), &["baz1", "baz2", "baz3"]);
+    /// ```
+    ///
+    /// [required]: crate::Arg::required()
+    #[inline]
+    pub fn allow_missing_positional(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::AllowMissingPositional)
+        } else {
+            self.unset_setting(AppSettings::AllowMissingPositional)
+        }
+    }
+}
+
+/// # Subcommand-specific Settings
+impl<'help> App<'help> {
+    /// Sets the short version of the subcommand flag without the preceding `-`.
+    ///
+    /// Allows the subcommand to be used as if it were an [`Arg::short`].
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let matches = Command::new("pacman")
+    ///     .subcommand(
+    ///         Command::new("sync").short_flag('S').arg(
+    ///             Arg::new("search")
+    ///                 .short('s')
+    ///                 .long("search")
+    ///                 .action(ArgAction::SetTrue)
+    ///                 .help("search remote repositories for matching strings"),
+    ///         ),
+    ///     )
+    ///     .get_matches_from(vec!["pacman", "-Ss"]);
+    ///
+    /// assert_eq!(matches.subcommand_name().unwrap(), "sync");
+    /// let sync_matches = matches.subcommand_matches("sync").unwrap();
+    /// assert!(*sync_matches.get_one::<bool>("search").expect("defaulted by clap"));
+    /// ```
+    /// [`Arg::short`]: Arg::short()
+    #[must_use]
+    pub fn short_flag(mut self, short: char) -> Self {
+        self.short_flag = Some(short);
+        self
+    }
+
+    /// Sets the long version of the subcommand flag without the preceding `--`.
+    ///
+    /// Allows the subcommand to be used as if it were an [`Arg::long`].
+    ///
+    /// **NOTE:** Any leading `-` characters will be stripped.
+    ///
+    /// # Examples
+    ///
+    /// To set `long_flag` use a word containing valid UTF-8 codepoints. If you supply a double leading
+    /// `--` such as `--sync` they will be stripped. Hyphens in the middle of the word; however,
+    /// will *not* be stripped (i.e. `sync-file` is allowed).
+    ///
+    /// ```
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let matches = Command::new("pacman")
+    ///     .subcommand(
+    ///         Command::new("sync").long_flag("sync").arg(
+    ///             Arg::new("search")
+    ///                 .short('s')
+    ///                 .long("search")
+    ///                 .action(ArgAction::SetTrue)
+    ///                 .help("search remote repositories for matching strings"),
+    ///         ),
+    ///     )
+    ///     .get_matches_from(vec!["pacman", "--sync", "--search"]);
+    ///
+    /// assert_eq!(matches.subcommand_name().unwrap(), "sync");
+    /// let sync_matches = matches.subcommand_matches("sync").unwrap();
+    /// assert!(*sync_matches.get_one::<bool>("search").expect("defaulted by clap"));
+    /// ```
+    ///
+    /// [`Arg::long`]: Arg::long()
+    #[must_use]
+    pub fn long_flag(mut self, long: &'help str) -> Self {
+        #[cfg(feature = "unstable-v4")]
+        {
+            self.long_flag = Some(long);
+        }
+        #[cfg(not(feature = "unstable-v4"))]
+        {
+            self.long_flag = Some(long.trim_start_matches(|c| c == '-'));
+        }
+        self
+    }
+
+    /// Sets a hidden alias to this subcommand.
+    ///
+    /// This allows the subcommand to be accessed via *either* the original name, or this given
+    /// alias. This is more efficient and easier than creating multiple hidden subcommands as one
+    /// only needs to check for the existence of this command, and not all aliased variants.
+    ///
+    /// **NOTE:** Aliases defined with this method are *hidden* from the help
+    /// message. If you're looking for aliases that will be displayed in the help
+    /// message, see [`Command::visible_alias`].
+    ///
+    /// **NOTE:** When using aliases and checking for the existence of a
+    /// particular subcommand within an [`ArgMatches`] struct, one only needs to
+    /// search for the original name and not all aliases.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///     .subcommand(Command::new("test")
+    ///         .alias("do-stuff"))
+    ///     .get_matches_from(vec!["myprog", "do-stuff"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    /// [`App::visible_alias`]: Command::visible_alias()
+    #[must_use]
+    pub fn alias<S: Into<&'help str>>(mut self, name: S) -> Self {
+        self.aliases.push((name.into(), false));
+        self
+    }
+
+    /// Add an alias, which functions as  "hidden" short flag subcommand
+    ///
+    /// This will automatically dispatch as if this subcommand was used. This is more efficient,
+    /// and easier than creating multiple hidden subcommands as one only needs to check for the
+    /// existence of this command, and not all variants.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///             .subcommand(Command::new("test").short_flag('t')
+    ///                 .short_flag_alias('d'))
+    ///             .get_matches_from(vec!["myprog", "-d"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    #[must_use]
+    pub fn short_flag_alias(mut self, name: char) -> Self {
+        assert!(name != '-', "short alias name cannot be `-`");
+        self.short_flag_aliases.push((name, false));
+        self
+    }
+
+    /// Add an alias, which functions as a "hidden" long flag subcommand.
+    ///
+    /// This will automatically dispatch as if this subcommand was used. This is more efficient,
+    /// and easier than creating multiple hidden subcommands as one only needs to check for the
+    /// existence of this command, and not all variants.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///             .subcommand(Command::new("test").long_flag("test")
+    ///                 .long_flag_alias("testing"))
+    ///             .get_matches_from(vec!["myprog", "--testing"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    #[must_use]
+    pub fn long_flag_alias(mut self, name: &'help str) -> Self {
+        self.long_flag_aliases.push((name, false));
+        self
+    }
+
+    /// Sets multiple hidden aliases to this subcommand.
+    ///
+    /// This allows the subcommand to be accessed via *either* the original name or any of the
+    /// given aliases. This is more efficient, and easier than creating multiple hidden subcommands
+    /// as one only needs to check for the existence of this command and not all aliased variants.
+    ///
+    /// **NOTE:** Aliases defined with this method are *hidden* from the help
+    /// message. If looking for aliases that will be displayed in the help
+    /// message, see [`Command::visible_aliases`].
+    ///
+    /// **NOTE:** When using aliases and checking for the existence of a
+    /// particular subcommand within an [`ArgMatches`] struct, one only needs to
+    /// search for the original name and not all aliases.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myprog")
+    ///     .subcommand(Command::new("test")
+    ///         .aliases(&["do-stuff", "do-tests", "tests"]))
+    ///         .arg(Arg::new("input")
+    ///             .help("the file to add")
+    ///             .required(false))
+    ///     .get_matches_from(vec!["myprog", "do-tests"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    /// [`App::visible_aliases`]: Command::visible_aliases()
+    #[must_use]
+    pub fn aliases(mut self, names: &[&'help str]) -> Self {
+        self.aliases.extend(names.iter().map(|n| (*n, false)));
+        self
+    }
+
+    /// Add aliases, which function as "hidden" short flag subcommands.
+    ///
+    /// These will automatically dispatch as if this subcommand was used. This is more efficient,
+    /// and easier than creating multiple hidden subcommands as one only needs to check for the
+    /// existence of this command, and not all variants.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///     .subcommand(Command::new("test").short_flag('t')
+    ///         .short_flag_aliases(&['a', 'b', 'c']))
+    ///         .arg(Arg::new("input")
+    ///             .help("the file to add")
+    ///             .required(false))
+    ///     .get_matches_from(vec!["myprog", "-a"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    #[must_use]
+    pub fn short_flag_aliases(mut self, names: &[char]) -> Self {
+        for s in names {
+            assert!(s != &'-', "short alias name cannot be `-`");
+            self.short_flag_aliases.push((*s, false));
+        }
+        self
+    }
+
+    /// Add aliases, which function as "hidden" long flag subcommands.
+    ///
+    /// These will automatically dispatch as if this subcommand was used. This is more efficient,
+    /// and easier than creating multiple hidden subcommands as one only needs to check for the
+    /// existence of this command, and not all variants.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///             .subcommand(Command::new("test").long_flag("test")
+    ///                 .long_flag_aliases(&["testing", "testall", "test_all"]))
+    ///                 .arg(Arg::new("input")
+    ///                             .help("the file to add")
+    ///                             .required(false))
+    ///             .get_matches_from(vec!["myprog", "--testing"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    #[must_use]
+    pub fn long_flag_aliases(mut self, names: &[&'help str]) -> Self {
+        for s in names {
+            self.long_flag_aliases.push((s, false));
+        }
+        self
+    }
+
+    /// Sets a visible alias to this subcommand.
+    ///
+    /// This allows the subcommand to be accessed via *either* the
+    /// original name or the given alias. This is more efficient and easier
+    /// than creating hidden subcommands as one only needs to check for
+    /// the existence of this command and not all aliased variants.
+    ///
+    /// **NOTE:** The alias defined with this method is *visible* from the help
+    /// message and displayed as if it were just another regular subcommand. If
+    /// looking for an alias that will not be displayed in the help message, see
+    /// [`Command::alias`].
+    ///
+    /// **NOTE:** When using aliases and checking for the existence of a
+    /// particular subcommand within an [`ArgMatches`] struct, one only needs to
+    /// search for the original name and not all aliases.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myprog")
+    ///     .subcommand(Command::new("test")
+    ///         .visible_alias("do-stuff"))
+    ///     .get_matches_from(vec!["myprog", "do-stuff"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    /// [`App::alias`]: Command::alias()
+    #[must_use]
+    pub fn visible_alias<S: Into<&'help str>>(mut self, name: S) -> Self {
+        self.aliases.push((name.into(), true));
+        self
+    }
+
+    /// Add an alias, which functions as  "visible" short flag subcommand
+    ///
+    /// This will automatically dispatch as if this subcommand was used. This is more efficient,
+    /// and easier than creating multiple hidden subcommands as one only needs to check for the
+    /// existence of this command, and not all variants.
+    ///
+    /// See also [`Command::short_flag_alias`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///             .subcommand(Command::new("test").short_flag('t')
+    ///                 .visible_short_flag_alias('d'))
+    ///             .get_matches_from(vec!["myprog", "-d"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    /// [`App::short_flag_alias`]: Command::short_flag_alias()
+    #[must_use]
+    pub fn visible_short_flag_alias(mut self, name: char) -> Self {
+        assert!(name != '-', "short alias name cannot be `-`");
+        self.short_flag_aliases.push((name, true));
+        self
+    }
+
+    /// Add an alias, which functions as a "visible" long flag subcommand.
+    ///
+    /// This will automatically dispatch as if this subcommand was used. This is more efficient,
+    /// and easier than creating multiple hidden subcommands as one only needs to check for the
+    /// existence of this command, and not all variants.
+    ///
+    /// See also [`Command::long_flag_alias`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///             .subcommand(Command::new("test").long_flag("test")
+    ///                 .visible_long_flag_alias("testing"))
+    ///             .get_matches_from(vec!["myprog", "--testing"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    /// [`App::long_flag_alias`]: Command::long_flag_alias()
+    #[must_use]
+    pub fn visible_long_flag_alias(mut self, name: &'help str) -> Self {
+        self.long_flag_aliases.push((name, true));
+        self
+    }
+
+    /// Sets multiple visible aliases to this subcommand.
+    ///
+    /// This allows the subcommand to be accessed via *either* the
+    /// original name or any of the given aliases. This is more efficient and easier
+    /// than creating multiple hidden subcommands as one only needs to check for
+    /// the existence of this command and not all aliased variants.
+    ///
+    /// **NOTE:** The alias defined with this method is *visible* from the help
+    /// message and displayed as if it were just another regular subcommand. If
+    /// looking for an alias that will not be displayed in the help message, see
+    /// [`Command::alias`].
+    ///
+    /// **NOTE:** When using aliases, and checking for the existence of a
+    /// particular subcommand within an [`ArgMatches`] struct, one only needs to
+    /// search for the original name and not all aliases.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///     .subcommand(Command::new("test")
+    ///         .visible_aliases(&["do-stuff", "tests"]))
+    ///     .get_matches_from(vec!["myprog", "do-stuff"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    /// [`App::alias`]: Command::alias()
+    #[must_use]
+    pub fn visible_aliases(mut self, names: &[&'help str]) -> Self {
+        self.aliases.extend(names.iter().map(|n| (*n, true)));
+        self
+    }
+
+    /// Add aliases, which function as *visible* short flag subcommands.
+    ///
+    /// See [`Command::short_flag_aliases`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///             .subcommand(Command::new("test").short_flag('b')
+    ///                 .visible_short_flag_aliases(&['t']))
+    ///             .get_matches_from(vec!["myprog", "-t"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    /// [`App::short_flag_aliases`]: Command::short_flag_aliases()
+    #[must_use]
+    pub fn visible_short_flag_aliases(mut self, names: &[char]) -> Self {
+        for s in names {
+            assert!(s != &'-', "short alias name cannot be `-`");
+            self.short_flag_aliases.push((*s, true));
+        }
+        self
+    }
+
+    /// Add aliases, which function as *visible* long flag subcommands.
+    ///
+    /// See [`Command::long_flag_aliases`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    /// let m = Command::new("myprog")
+    ///             .subcommand(Command::new("test").long_flag("test")
+    ///                 .visible_long_flag_aliases(&["testing", "testall", "test_all"]))
+    ///             .get_matches_from(vec!["myprog", "--testing"]);
+    /// assert_eq!(m.subcommand_name(), Some("test"));
+    /// ```
+    /// [`App::long_flag_aliases`]: Command::long_flag_aliases()
+    #[must_use]
+    pub fn visible_long_flag_aliases(mut self, names: &[&'help str]) -> Self {
+        for s in names {
+            self.long_flag_aliases.push((s, true));
+        }
+        self
+    }
+
+    /// Set the placement of this subcommand within the help.
+    ///
+    /// Subcommands with a lower value will be displayed first in the help message.  Subcommands
+    /// with duplicate display orders will be displayed in alphabetical order.
+    ///
+    /// This is helpful when one would like to emphasize frequently used subcommands, or prioritize
+    /// those towards the top of the list.
+    ///
+    /// **NOTE:** The default is 999 for all subcommands.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, };
+    /// let m = Command::new("cust-ord")
+    ///     .subcommand(Command::new("alpha") // typically subcommands are grouped
+    ///                                                // alphabetically by name. Subcommands
+    ///                                                // without a display_order have a value of
+    ///                                                // 999 and are displayed alphabetically with
+    ///                                                // all other 999 subcommands
+    ///         .about("Some help and text"))
+    ///     .subcommand(Command::new("beta")
+    ///         .display_order(1)   // In order to force this subcommand to appear *first*
+    ///                             // all we have to do is give it a value lower than 999.
+    ///                             // Any other subcommands with a value of 1 will be displayed
+    ///                             // alphabetically with this one...then 2 values, then 3, etc.
+    ///         .about("I should be first!"))
+    ///     .get_matches_from(vec![
+    ///         "cust-ord", "--help"
+    ///     ]);
+    /// ```
+    ///
+    /// The above example displays the following help message
+    ///
+    /// ```text
+    /// cust-ord
+    ///
+    /// USAGE:
+    ///     cust-ord [OPTIONS]
+    ///
+    /// OPTIONS:
+    ///     -h, --help       Print help information
+    ///     -V, --version    Print version information
+    ///
+    /// SUBCOMMANDS:
+    ///     beta    I should be first!
+    ///     alpha   Some help and text
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn display_order(mut self, ord: usize) -> Self {
+        self.disp_ord = Some(ord);
+        self
+    }
+
+    /// Specifies that this [`subcommand`] should be hidden from help messages
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .subcommand(
+    ///         Command::new("test").hide(true)
+    ///     )
+    /// # ;
+    /// ```
+    ///
+    /// [`subcommand`]: crate::Command::subcommand()
+    #[inline]
+    pub fn hide(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::Hidden)
+        } else {
+            self.unset_setting(AppSettings::Hidden)
+        }
+    }
+
+    /// If no [`subcommand`] is present at runtime, error and exit gracefully.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, ErrorKind};
+    /// let err = Command::new("myprog")
+    ///     .subcommand_required(true)
+    ///     .subcommand(Command::new("test"))
+    ///     .try_get_matches_from(vec![
+    ///         "myprog",
+    ///     ]);
+    /// assert!(err.is_err());
+    /// assert_eq!(err.unwrap_err().kind(), ErrorKind::MissingSubcommand);
+    /// # ;
+    /// ```
+    ///
+    /// [`subcommand`]: crate::Command::subcommand()
+    pub fn subcommand_required(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::SubcommandRequired)
+        } else {
+            self.unset_setting(AppSettings::SubcommandRequired)
+        }
+    }
+
+    /// Assume unexpected positional arguments are a [`subcommand`].
+    ///
+    /// Arguments will be stored in the `""` argument in the [`ArgMatches`]
+    ///
+    /// **NOTE:** Use this setting with caution,
+    /// as a truly unexpected argument (i.e. one that is *NOT* an external subcommand)
+    /// will **not** cause an error and instead be treated as a potential subcommand.
+    /// One should check for such cases manually and inform the user appropriately.
+    ///
+    /// **NOTE:** A built-in subcommand will be parsed as an external subcommand when escaped with
+    /// `--`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// // Assume there is an external subcommand named "subcmd"
+    /// let m = Command::new("myprog")
+    ///     .allow_external_subcommands(true)
+    ///     .get_matches_from(vec![
+    ///         "myprog", "subcmd", "--option", "value", "-fff", "--flag"
+    ///     ]);
+    ///
+    /// // All trailing arguments will be stored under the subcommand's sub-matches using an empty
+    /// // string argument name
+    /// match m.subcommand() {
+    ///     Some((external, ext_m)) => {
+    ///          let ext_args: Vec<&str> = ext_m.values_of("").unwrap().collect();
+    ///          assert_eq!(external, "subcmd");
+    ///          assert_eq!(ext_args, ["--option", "value", "-fff", "--flag"]);
+    ///     },
+    ///     _ => {},
+    /// }
+    /// ```
+    ///
+    /// [`subcommand`]: crate::Command::subcommand()
+    /// [`ArgMatches`]: crate::ArgMatches
+    /// [`ErrorKind::UnknownArgument`]: crate::ErrorKind::UnknownArgument
+    pub fn allow_external_subcommands(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::AllowExternalSubcommands)
+        } else {
+            self.unset_setting(AppSettings::AllowExternalSubcommands)
+        }
+    }
+
+    /// Specifies that external subcommands that are invalid UTF-8 should *not* be treated as an error.
+    ///
+    /// **NOTE:** Using external subcommand argument values with invalid UTF-8 requires using
+    /// [`ArgMatches::values_of_os`] or [`ArgMatches::values_of_lossy`] for those particular
+    /// arguments which may contain invalid UTF-8 values
+    ///
+    /// **NOTE:** Setting this requires [`Command::allow_external_subcommands`]
+    ///
+    /// # Platform Specific
+    ///
+    /// Non Windows systems only
+    ///
+    /// # Examples
+    ///
+    #[cfg_attr(not(unix), doc = " ```ignore")]
+    #[cfg_attr(unix, doc = " ```")]
+    /// # use clap::Command;
+    /// // Assume there is an external subcommand named "subcmd"
+    /// let m = Command::new("myprog")
+    ///     .allow_invalid_utf8_for_external_subcommands(true)
+    ///     .allow_external_subcommands(true)
+    ///     .get_matches_from(vec![
+    ///         "myprog", "subcmd", "--option", "value", "-fff", "--flag"
+    ///     ]);
+    ///
+    /// // All trailing arguments will be stored under the subcommand's sub-matches using an empty
+    /// // string argument name
+    /// match m.subcommand() {
+    ///     Some((external, ext_m)) => {
+    ///          let ext_args: Vec<&std::ffi::OsStr> = ext_m.values_of_os("").unwrap().collect();
+    ///          assert_eq!(external, "subcmd");
+    ///          assert_eq!(ext_args, ["--option", "value", "-fff", "--flag"]);
+    ///     },
+    ///     _ => {},
+    /// }
+    /// ```
+    ///
+    /// [`ArgMatches::values_of_os`]: crate::ArgMatches::values_of_os()
+    /// [`ArgMatches::values_of_lossy`]: crate::ArgMatches::values_of_lossy()
+    /// [`subcommands`]: crate::Command::subcommand()
+    pub fn allow_invalid_utf8_for_external_subcommands(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::AllowInvalidUtf8ForExternalSubcommands)
+        } else {
+            self.unset_setting(AppSettings::AllowInvalidUtf8ForExternalSubcommands)
+        }
+    }
+
+    /// Specifies that use of an argument prevents the use of [`subcommands`].
+    ///
+    /// By default `clap` allows arguments between subcommands such
+    /// as `<cmd> [cmd_args] <subcmd> [subcmd_args] <subsubcmd> [subsubcmd_args]`.
+    ///
+    /// This setting disables that functionality and says that arguments can
+    /// only follow the *final* subcommand. For instance using this setting
+    /// makes only the following invocations possible:
+    ///
+    /// * `<cmd> <subcmd> <subsubcmd> [subsubcmd_args]`
+    /// * `<cmd> <subcmd> [subcmd_args]`
+    /// * `<cmd> [cmd_args]`
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// Command::new("myprog")
+    ///     .args_conflicts_with_subcommands(true);
+    /// ```
+    ///
+    /// [`subcommands`]: crate::Command::subcommand()
+    pub fn args_conflicts_with_subcommands(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::ArgsNegateSubcommands)
+        } else {
+            self.unset_setting(AppSettings::ArgsNegateSubcommands)
+        }
+    }
+
+    /// Prevent subcommands from being consumed as an arguments value.
+    ///
+    /// By default, if an option taking multiple values is followed by a subcommand, the
+    /// subcommand will be parsed as another value.
+    ///
+    /// ```text
+    /// cmd --foo val1 val2 subcommand
+    ///           --------- ----------
+    ///             values   another value
+    /// ```
+    ///
+    /// This setting instructs the parser to stop when encountering a subcommand instead of
+    /// greedily consuming arguments.
+    ///
+    /// ```text
+    /// cmd --foo val1 val2 subcommand
+    ///           --------- ----------
+    ///             values   subcommand
+    /// ```
+    ///
+    /// **Note:** Make sure you apply it as `global_setting` if you want this setting
+    /// to be propagated to subcommands and sub-subcommands!
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let cmd = Command::new("cmd").subcommand(Command::new("sub")).arg(
+    ///     Arg::new("arg")
+    ///         .long("arg")
+    ///         .multiple_values(true)
+    ///         .takes_value(true),
+    /// );
+    ///
+    /// let matches = cmd
+    ///     .clone()
+    ///     .try_get_matches_from(&["cmd", "--arg", "1", "2", "3", "sub"])
+    ///     .unwrap();
+    /// assert_eq!(
+    ///     matches.values_of("arg").unwrap().collect::<Vec<_>>(),
+    ///     &["1", "2", "3", "sub"]
+    /// );
+    /// assert!(matches.subcommand_matches("sub").is_none());
+    ///
+    /// let matches = cmd
+    ///     .subcommand_precedence_over_arg(true)
+    ///     .try_get_matches_from(&["cmd", "--arg", "1", "2", "3", "sub"])
+    ///     .unwrap();
+    /// assert_eq!(
+    ///     matches.values_of("arg").unwrap().collect::<Vec<_>>(),
+    ///     &["1", "2", "3"]
+    /// );
+    /// assert!(matches.subcommand_matches("sub").is_some());
+    /// ```
+    pub fn subcommand_precedence_over_arg(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::SubcommandPrecedenceOverArg)
+        } else {
+            self.unset_setting(AppSettings::SubcommandPrecedenceOverArg)
+        }
+    }
+
+    /// Allows [`subcommands`] to override all requirements of the parent command.
+    ///
+    /// For example, if you had a subcommand or top level application with a required argument
+    /// that is only required as long as there is no subcommand present,
+    /// using this setting would allow you to set those arguments to [`Arg::required(true)`]
+    /// and yet receive no error so long as the user uses a valid subcommand instead.
+    ///
+    /// **NOTE:** This defaults to false (using subcommand does *not* negate requirements)
+    ///
+    /// # Examples
+    ///
+    /// This first example shows that it is an error to not use a required argument
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let err = Command::new("myprog")
+    ///     .subcommand_negates_reqs(true)
+    ///     .arg(Arg::new("opt").required(true))
+    ///     .subcommand(Command::new("test"))
+    ///     .try_get_matches_from(vec![
+    ///         "myprog"
+    ///     ]);
+    /// assert!(err.is_err());
+    /// assert_eq!(err.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// # ;
+    /// ```
+    ///
+    /// This next example shows that it is no longer error to not use a required argument if a
+    /// valid subcommand is used.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let noerr = Command::new("myprog")
+    ///     .subcommand_negates_reqs(true)
+    ///     .arg(Arg::new("opt").required(true))
+    ///     .subcommand(Command::new("test"))
+    ///     .try_get_matches_from(vec![
+    ///         "myprog", "test"
+    ///     ]);
+    /// assert!(noerr.is_ok());
+    /// # ;
+    /// ```
+    ///
+    /// [`Arg::required(true)`]: crate::Arg::required()
+    /// [`subcommands`]: crate::Command::subcommand()
+    pub fn subcommand_negates_reqs(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::SubcommandsNegateReqs)
+        } else {
+            self.unset_setting(AppSettings::SubcommandsNegateReqs)
+        }
+    }
+
+    /// Multiple-personality program dispatched on the binary name (`argv[0]`)
+    ///
+    /// A "multicall" executable is a single executable
+    /// that contains a variety of applets,
+    /// and decides which applet to run based on the name of the file.
+    /// The executable can be called from different names by creating hard links
+    /// or symbolic links to it.
+    ///
+    /// This is desirable for:
+    /// - Easy distribution, a single binary that can install hardlinks to access the different
+    ///   personalities.
+    /// - Minimal binary size by sharing common code (e.g. standard library, clap)
+    /// - Custom shells or REPLs where there isn't a single top-level command
+    ///
+    /// Setting `multicall` will cause
+    /// - `argv[0]` to be stripped to the base name and parsed as the first argument, as if
+    ///   [`Command::no_binary_name`][App::no_binary_name] was set.
+    /// - Help and errors to report subcommands as if they were the top-level command
+    ///
+    /// When the subcommand is not present, there are several strategies you may employ, depending
+    /// on your needs:
+    /// - Let the error percolate up normally
+    /// - Print a specialized error message using the
+    ///   [`Error::context`][crate::Error::context]
+    /// - Print the [help][App::write_help] but this might be ambiguous
+    /// - Disable `multicall` and re-parse it
+    /// - Disable `multicall` and re-parse it with a specific subcommand
+    ///
+    /// When detecting the error condition, the [`ErrorKind`] isn't sufficient as a sub-subcommand
+    /// might report the same error.  Enable
+    /// [`allow_external_subcommands`][App::allow_external_subcommands] if you want to specifically
+    /// get the unrecognized binary name.
+    ///
+    /// **NOTE:** Multicall can't be used with [`no_binary_name`] since they interpret
+    /// the command name in incompatible ways.
+    ///
+    /// **NOTE:** The multicall command cannot have arguments.
+    ///
+    /// **NOTE:** Applets are slightly semantically different from subcommands,
+    /// so it's recommended to use [`Command::subcommand_help_heading`] and
+    /// [`Command::subcommand_value_name`] to change the descriptive text as above.
+    ///
+    /// # Examples
+    ///
+    /// `hostname` is an example of a multicall executable.
+    /// Both `hostname` and `dnsdomainname` are provided by the same executable
+    /// and which behaviour to use is based on the executable file name.
+    ///
+    /// This is desirable when the executable has a primary purpose
+    /// but there is related functionality that would be convenient to provide
+    /// and implement it to be in the same executable.
+    ///
+    /// The name of the cmd is essentially unused
+    /// and may be the same as the name of a subcommand.
+    ///
+    /// The names of the immediate subcommands of the Command
+    /// are matched against the basename of the first argument,
+    /// which is conventionally the path of the executable.
+    ///
+    /// This does not allow the subcommand to be passed as the first non-path argument.
+    ///
+    /// ```rust
+    /// # use clap::{Command, ErrorKind};
+    /// let mut cmd = Command::new("hostname")
+    ///     .multicall(true)
+    ///     .subcommand(Command::new("hostname"))
+    ///     .subcommand(Command::new("dnsdomainname"));
+    /// let m = cmd.try_get_matches_from_mut(&["/usr/bin/hostname", "dnsdomainname"]);
+    /// assert!(m.is_err());
+    /// assert_eq!(m.unwrap_err().kind(), ErrorKind::UnknownArgument);
+    /// let m = cmd.get_matches_from(&["/usr/bin/dnsdomainname"]);
+    /// assert_eq!(m.subcommand_name(), Some("dnsdomainname"));
+    /// ```
+    ///
+    /// Busybox is another common example of a multicall executable
+    /// with a subcommmand for each applet that can be run directly,
+    /// e.g. with the `cat` applet being run by running `busybox cat`,
+    /// or with `cat` as a link to the `busybox` binary.
+    ///
+    /// This is desirable when the launcher program has additional options
+    /// or it is useful to run the applet without installing a symlink
+    /// e.g. to test the applet without installing it
+    /// or there may already be a command of that name installed.
+    ///
+    /// To make an applet usable as both a multicall link and a subcommand
+    /// the subcommands must be defined both in the top-level Command
+    /// and as subcommands of the "main" applet.
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// fn applet_commands() -> [Command<'static>; 2] {
+    ///     [Command::new("true"), Command::new("false")]
+    /// }
+    /// let mut cmd = Command::new("busybox")
+    ///     .multicall(true)
+    ///     .subcommand(
+    ///         Command::new("busybox")
+    ///             .subcommand_value_name("APPLET")
+    ///             .subcommand_help_heading("APPLETS")
+    ///             .subcommands(applet_commands()),
+    ///     )
+    ///     .subcommands(applet_commands());
+    /// // When called from the executable's canonical name
+    /// // its applets can be matched as subcommands.
+    /// let m = cmd.try_get_matches_from_mut(&["/usr/bin/busybox", "true"]).unwrap();
+    /// assert_eq!(m.subcommand_name(), Some("busybox"));
+    /// assert_eq!(m.subcommand().unwrap().1.subcommand_name(), Some("true"));
+    /// // When called from a link named after an applet that applet is matched.
+    /// let m = cmd.get_matches_from(&["/usr/bin/true"]);
+    /// assert_eq!(m.subcommand_name(), Some("true"));
+    /// ```
+    ///
+    /// [`no_binary_name`]: crate::Command::no_binary_name
+    /// [`App::subcommand_value_name`]: crate::Command::subcommand_value_name
+    /// [`App::subcommand_help_heading`]: crate::Command::subcommand_help_heading
+    #[inline]
+    pub fn multicall(self, yes: bool) -> Self {
+        if yes {
+            self.setting(AppSettings::Multicall)
+        } else {
+            self.unset_setting(AppSettings::Multicall)
+        }
+    }
+
+    /// Sets the value name used for subcommands when printing usage and help.
+    ///
+    /// By default, this is "SUBCOMMAND".
+    ///
+    /// See also [`Command::subcommand_help_heading`]
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .subcommand(Command::new("sub1"))
+    ///     .print_help()
+    /// # ;
+    /// ```
+    ///
+    /// will produce
+    ///
+    /// ```text
+    /// myprog
+    ///
+    /// USAGE:
+    ///     myprog [SUBCOMMAND]
+    ///
+    /// OPTIONS:
+    ///     -h, --help       Print help information
+    ///     -V, --version    Print version information
+    ///
+    /// SUBCOMMANDS:
+    ///     help    Print this message or the help of the given subcommand(s)
+    ///     sub1
+    /// ```
+    ///
+    /// but usage of `subcommand_value_name`
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .subcommand(Command::new("sub1"))
+    ///     .subcommand_value_name("THING")
+    ///     .print_help()
+    /// # ;
+    /// ```
+    ///
+    /// will produce
+    ///
+    /// ```text
+    /// myprog
+    ///
+    /// USAGE:
+    ///     myprog [THING]
+    ///
+    /// OPTIONS:
+    ///     -h, --help       Print help information
+    ///     -V, --version    Print version information
+    ///
+    /// SUBCOMMANDS:
+    ///     help    Print this message or the help of the given subcommand(s)
+    ///     sub1
+    /// ```
+    #[must_use]
+    pub fn subcommand_value_name<S>(mut self, value_name: S) -> Self
+    where
+        S: Into<&'help str>,
+    {
+        self.subcommand_value_name = Some(value_name.into());
+        self
+    }
+
+    /// Sets the help heading used for subcommands when printing usage and help.
+    ///
+    /// By default, this is "SUBCOMMANDS".
+    ///
+    /// See also [`Command::subcommand_value_name`]
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .subcommand(Command::new("sub1"))
+    ///     .print_help()
+    /// # ;
+    /// ```
+    ///
+    /// will produce
+    ///
+    /// ```text
+    /// myprog
+    ///
+    /// USAGE:
+    ///     myprog [SUBCOMMAND]
+    ///
+    /// OPTIONS:
+    ///     -h, --help       Print help information
+    ///     -V, --version    Print version information
+    ///
+    /// SUBCOMMANDS:
+    ///     help    Print this message or the help of the given subcommand(s)
+    ///     sub1
+    /// ```
+    ///
+    /// but usage of `subcommand_help_heading`
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg};
+    /// Command::new("myprog")
+    ///     .subcommand(Command::new("sub1"))
+    ///     .subcommand_help_heading("THINGS")
+    ///     .print_help()
+    /// # ;
+    /// ```
+    ///
+    /// will produce
+    ///
+    /// ```text
+    /// myprog
+    ///
+    /// USAGE:
+    ///     myprog [SUBCOMMAND]
+    ///
+    /// OPTIONS:
+    ///     -h, --help       Print help information
+    ///     -V, --version    Print version information
+    ///
+    /// THINGS:
+    ///     help    Print this message or the help of the given subcommand(s)
+    ///     sub1
+    /// ```
+    #[must_use]
+    pub fn subcommand_help_heading<T>(mut self, heading: T) -> Self
+    where
+        T: Into<&'help str>,
+    {
+        self.subcommand_heading = Some(heading.into());
+        self
+    }
+}
+
+/// # Reflection
+impl<'help> App<'help> {
+    #[inline]
+    pub(crate) fn get_usage_name(&self) -> Option<&str> {
+        self.usage_name.as_deref()
+    }
+
+    /// Get the name of the binary.
+    #[inline]
+    pub fn get_display_name(&self) -> Option<&str> {
+        self.display_name.as_deref()
+    }
+
+    /// Get the name of the binary.
+    #[inline]
+    pub fn get_bin_name(&self) -> Option<&str> {
+        self.bin_name.as_deref()
+    }
+
+    /// Set binary name. Uses `&mut self` instead of `self`.
+    pub fn set_bin_name<S: Into<String>>(&mut self, name: S) {
+        self.bin_name = Some(name.into());
+    }
+
+    /// Get the name of the cmd.
+    #[inline]
+    pub fn get_name(&self) -> &str {
+        &self.name
+    }
+
+    /// Get the version of the cmd.
+    #[inline]
+    pub fn get_version(&self) -> Option<&'help str> {
+        self.version
+    }
+
+    /// Get the long version of the cmd.
+    #[inline]
+    pub fn get_long_version(&self) -> Option<&'help str> {
+        self.long_version
+    }
+
+    /// Get the authors of the cmd.
+    #[inline]
+    pub fn get_author(&self) -> Option<&'help str> {
+        self.author
+    }
+
+    /// Get the short flag of the subcommand.
+    #[inline]
+    pub fn get_short_flag(&self) -> Option<char> {
+        self.short_flag
+    }
+
+    /// Get the long flag of the subcommand.
+    #[inline]
+    pub fn get_long_flag(&self) -> Option<&'help str> {
+        self.long_flag
+    }
+
+    /// Get the help message specified via [`Command::about`].
+    ///
+    /// [`App::about`]: Command::about()
+    #[inline]
+    pub fn get_about(&self) -> Option<&'help str> {
+        self.about
+    }
+
+    /// Get the help message specified via [`Command::long_about`].
+    ///
+    /// [`App::long_about`]: Command::long_about()
+    #[inline]
+    pub fn get_long_about(&self) -> Option<&'help str> {
+        self.long_about
+    }
+
+    /// Deprecated, replaced with [`Command::get_next_help_heading`]
+    #[inline]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `App::get_next_help_heading`")
+    )]
+    pub fn get_help_heading(&self) -> Option<&'help str> {
+        self.get_next_help_heading()
+    }
+
+    /// Get the custom section heading specified via [`Command::help_heading`].
+    ///
+    /// [`App::help_heading`]: Command::help_heading()
+    #[inline]
+    pub fn get_next_help_heading(&self) -> Option<&'help str> {
+        self.current_help_heading
+    }
+
+    /// Iterate through the *visible* aliases for this subcommand.
+    #[inline]
+    pub fn get_visible_aliases(&self) -> impl Iterator<Item = &'help str> + '_ {
+        self.aliases.iter().filter(|(_, vis)| *vis).map(|a| a.0)
+    }
+
+    /// Iterate through the *visible* short aliases for this subcommand.
+    #[inline]
+    pub fn get_visible_short_flag_aliases(&self) -> impl Iterator<Item = char> + '_ {
+        self.short_flag_aliases
+            .iter()
+            .filter(|(_, vis)| *vis)
+            .map(|a| a.0)
+    }
+
+    /// Iterate through the *visible* long aliases for this subcommand.
+    #[inline]
+    pub fn get_visible_long_flag_aliases(&self) -> impl Iterator<Item = &'help str> + '_ {
+        self.long_flag_aliases
+            .iter()
+            .filter(|(_, vis)| *vis)
+            .map(|a| a.0)
+    }
+
+    /// Iterate through the set of *all* the aliases for this subcommand, both visible and hidden.
+    #[inline]
+    pub fn get_all_aliases(&self) -> impl Iterator<Item = &str> + '_ {
+        self.aliases.iter().map(|a| a.0)
+    }
+
+    /// Iterate through the set of *all* the short aliases for this subcommand, both visible and hidden.
+    #[inline]
+    pub fn get_all_short_flag_aliases(&self) -> impl Iterator<Item = char> + '_ {
+        self.short_flag_aliases.iter().map(|a| a.0)
+    }
+
+    /// Iterate through the set of *all* the long aliases for this subcommand, both visible and hidden.
+    #[inline]
+    pub fn get_all_long_flag_aliases(&self) -> impl Iterator<Item = &'help str> + '_ {
+        self.long_flag_aliases.iter().map(|a| a.0)
+    }
+
+    /// Check if the given [`AppSettings`] variant is currently set on the `Command`.
+    ///
+    /// This checks both [local] and [global settings].
+    ///
+    /// [local]: Command::setting()
+    /// [global settings]: Command::global_setting()
+    #[inline]
+    pub fn is_set(&self, s: AppSettings) -> bool {
+        self.settings.is_set(s) || self.g_settings.is_set(s)
+    }
+
+    /// Should we color the output?
+    #[inline(never)]
+    pub fn get_color(&self) -> ColorChoice {
+        debug!("Command::color: Color setting...");
+
+        if cfg!(feature = "color") {
+            #[allow(deprecated)]
+            if self.is_set(AppSettings::ColorNever) {
+                debug!("Never");
+                ColorChoice::Never
+            } else if self.is_set(AppSettings::ColorAlways) {
+                debug!("Always");
+                ColorChoice::Always
+            } else {
+                debug!("Auto");
+                ColorChoice::Auto
+            }
+        } else {
+            ColorChoice::Never
+        }
+    }
+
+    /// Iterate through the set of subcommands, getting a reference to each.
+    #[inline]
+    pub fn get_subcommands(&self) -> impl Iterator<Item = &App<'help>> {
+        self.subcommands.iter()
+    }
+
+    /// Iterate through the set of subcommands, getting a mutable reference to each.
+    #[inline]
+    pub fn get_subcommands_mut(&mut self) -> impl Iterator<Item = &mut App<'help>> {
+        self.subcommands.iter_mut()
+    }
+
+    /// Returns `true` if this `Command` has subcommands.
+    #[inline]
+    pub fn has_subcommands(&self) -> bool {
+        !self.subcommands.is_empty()
+    }
+
+    /// Returns the help heading for listing subcommands.
+    #[inline]
+    pub fn get_subcommand_help_heading(&self) -> Option<&str> {
+        self.subcommand_heading
+    }
+
+    /// Deprecated, replaced with [`App::get_subcommand_help_heading`]
+    #[inline]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `App::get_subcommand_help_heading`"
+        )
+    )]
+    pub fn get_subommand_help_heading(&self) -> Option<&str> {
+        self.get_subcommand_help_heading()
+    }
+
+    /// Returns the subcommand value name.
+    #[inline]
+    pub fn get_subcommand_value_name(&self) -> Option<&str> {
+        self.subcommand_value_name
+    }
+
+    /// Returns the help heading for listing subcommands.
+    #[inline]
+    pub fn get_before_help(&self) -> Option<&str> {
+        self.before_help
+    }
+
+    /// Returns the help heading for listing subcommands.
+    #[inline]
+    pub fn get_before_long_help(&self) -> Option<&str> {
+        self.before_long_help
+    }
+
+    /// Returns the help heading for listing subcommands.
+    #[inline]
+    pub fn get_after_help(&self) -> Option<&str> {
+        self.after_help
+    }
+
+    /// Returns the help heading for listing subcommands.
+    #[inline]
+    pub fn get_after_long_help(&self) -> Option<&str> {
+        self.after_long_help
+    }
+
+    /// Find subcommand such that its name or one of aliases equals `name`.
+    ///
+    /// This does not recurse through subcommands of subcommands.
+    #[inline]
+    pub fn find_subcommand<T>(&self, name: &T) -> Option<&App<'help>>
+    where
+        T: PartialEq<str> + ?Sized,
+    {
+        self.get_subcommands().find(|s| s.aliases_to(name))
+    }
+
+    /// Find subcommand such that its name or one of aliases equals `name`, returning
+    /// a mutable reference to the subcommand.
+    ///
+    /// This does not recurse through subcommands of subcommands.
+    #[inline]
+    pub fn find_subcommand_mut<T>(&mut self, name: &T) -> Option<&mut App<'help>>
+    where
+        T: PartialEq<str> + ?Sized,
+    {
+        self.get_subcommands_mut().find(|s| s.aliases_to(name))
+    }
+
+    /// Iterate through the set of groups.
+    #[inline]
+    pub fn get_groups(&self) -> impl Iterator<Item = &ArgGroup<'help>> {
+        self.groups.iter()
+    }
+
+    /// Iterate through the set of arguments.
+    #[inline]
+    pub fn get_arguments(&self) -> impl Iterator<Item = &Arg<'help>> {
+        self.args.args()
+    }
+
+    /// Iterate through the *positionals* arguments.
+    #[inline]
+    pub fn get_positionals(&self) -> impl Iterator<Item = &Arg<'help>> {
+        self.get_arguments().filter(|a| a.is_positional())
+    }
+
+    /// Iterate through the *options*.
+    pub fn get_opts(&self) -> impl Iterator<Item = &Arg<'help>> {
+        self.get_arguments()
+            .filter(|a| a.is_takes_value_set() && !a.is_positional())
+    }
+
+    /// Get a list of all arguments the given argument conflicts with.
+    ///
+    /// If the provided argument is declared as global, the conflicts will be determined
+    /// based on the propagation rules of global arguments.
+    ///
+    /// ### Panics
+    ///
+    /// If the given arg contains a conflict with an argument that is unknown to
+    /// this `Command`.
+    pub fn get_arg_conflicts_with(&self, arg: &Arg) -> Vec<&Arg<'help>> // FIXME: This could probably have been an iterator
+    {
+        if arg.is_global_set() {
+            self.get_global_arg_conflicts_with(arg)
+        } else {
+            let mut result = Vec::new();
+            for id in arg.blacklist.iter() {
+                if let Some(arg) = self.find(id) {
+                    result.push(arg);
+                } else if let Some(group) = self.find_group(id) {
+                    result.extend(
+                        self.unroll_args_in_group(&group.id)
+                            .iter()
+                            .map(|id| self.find(id).expect(INTERNAL_ERROR_MSG)),
+                    );
+                } else {
+                    panic!("Command::get_arg_conflicts_with: The passed arg conflicts with an arg unknown to the cmd");
+                }
+            }
+            result
+        }
+    }
+
+    // Get a unique list of all arguments of all commands and continuous subcommands the given argument conflicts with.
+    //
+    // This behavior follows the propagation rules of global arguments.
+    // It is useful for finding conflicts for arguments declared as global.
+    //
+    // ### Panics
+    //
+    // If the given arg contains a conflict with an argument that is unknown to
+    // this `App`.
+    fn get_global_arg_conflicts_with(&self, arg: &Arg) -> Vec<&Arg<'help>> // FIXME: This could probably have been an iterator
+    {
+        arg.blacklist
+            .iter()
+            .map(|id| {
+                self.args
+                    .args()
+                    .chain(
+                        self.get_subcommands_containing(arg)
+                            .iter()
+                            .flat_map(|x| x.args.args()),
+                    )
+                    .find(|arg| arg.id == *id)
+                    .expect(
+                        "Command::get_arg_conflicts_with: \
+                    The passed arg conflicts with an arg unknown to the cmd",
+                    )
+            })
+            .collect()
+    }
+
+    // Get a list of subcommands which contain the provided Argument
+    //
+    // This command will only include subcommands in its list for which the subcommands
+    // parent also contains the Argument.
+    //
+    // This search follows the propagation rules of global arguments.
+    // It is useful to finding subcommands, that have inherited a global argument.
+    //
+    // **NOTE:** In this case only Sucommand_1 will be included
+    //   Subcommand_1 (contains Arg)
+    //     Subcommand_1.1 (doesn't contain Arg)
+    //       Subcommand_1.1.1 (contains Arg)
+    //
+    fn get_subcommands_containing(&self, arg: &Arg) -> Vec<&App<'help>> {
+        let mut vec = std::vec::Vec::new();
+        for idx in 0..self.subcommands.len() {
+            if self.subcommands[idx].args.args().any(|ar| ar.id == arg.id) {
+                vec.push(&self.subcommands[idx]);
+                vec.append(&mut self.subcommands[idx].get_subcommands_containing(arg));
+            }
+        }
+        vec
+    }
+
+    /// Report whether [`Command::no_binary_name`] is set
+    pub fn is_no_binary_name_set(&self) -> bool {
+        self.is_set(AppSettings::NoBinaryName)
+    }
+
+    /// Report whether [`Command::ignore_errors`] is set
+    pub(crate) fn is_ignore_errors_set(&self) -> bool {
+        self.is_set(AppSettings::IgnoreErrors)
+    }
+
+    /// Report whether [`Command::dont_delimit_trailing_values`] is set
+    pub fn is_dont_delimit_trailing_values_set(&self) -> bool {
+        self.is_set(AppSettings::DontDelimitTrailingValues)
+    }
+
+    /// Report whether [`Command::disable_version_flag`] is set
+    pub fn is_disable_version_flag_set(&self) -> bool {
+        self.is_set(AppSettings::DisableVersionFlag)
+    }
+
+    /// Report whether [`Command::propagate_version`] is set
+    pub fn is_propagate_version_set(&self) -> bool {
+        self.is_set(AppSettings::PropagateVersion)
+    }
+
+    /// Report whether [`Command::next_line_help`] is set
+    pub fn is_next_line_help_set(&self) -> bool {
+        self.is_set(AppSettings::NextLineHelp)
+    }
+
+    /// Report whether [`Command::disable_help_flag`] is set
+    pub fn is_disable_help_flag_set(&self) -> bool {
+        self.is_set(AppSettings::DisableHelpFlag)
+    }
+
+    /// Report whether [`Command::disable_help_subcommand`] is set
+    pub fn is_disable_help_subcommand_set(&self) -> bool {
+        self.is_set(AppSettings::DisableHelpSubcommand)
+    }
+
+    /// Report whether [`Command::disable_colored_help`] is set
+    pub fn is_disable_colored_help_set(&self) -> bool {
+        self.is_set(AppSettings::DisableColoredHelp)
+    }
+
+    /// Report whether [`Command::help_expected`] is set
+    #[cfg(debug_assertions)]
+    pub(crate) fn is_help_expected_set(&self) -> bool {
+        self.is_set(AppSettings::HelpExpected)
+    }
+
+    /// Report whether [`Command::dont_collapse_args_in_usage`] is set
+    pub fn is_dont_collapse_args_in_usage_set(&self) -> bool {
+        self.is_set(AppSettings::DontCollapseArgsInUsage)
+    }
+
+    /// Report whether [`Command::infer_long_args`] is set
+    pub(crate) fn is_infer_long_args_set(&self) -> bool {
+        self.is_set(AppSettings::InferLongArgs)
+    }
+
+    /// Report whether [`Command::infer_subcommands`] is set
+    pub(crate) fn is_infer_subcommands_set(&self) -> bool {
+        self.is_set(AppSettings::InferSubcommands)
+    }
+
+    /// Report whether [`Command::arg_required_else_help`] is set
+    pub fn is_arg_required_else_help_set(&self) -> bool {
+        self.is_set(AppSettings::ArgRequiredElseHelp)
+    }
+
+    /// Report whether [`Command::allow_hyphen_values`] is set
+    pub(crate) fn is_allow_hyphen_values_set(&self) -> bool {
+        self.is_set(AppSettings::AllowHyphenValues)
+    }
+
+    /// Report whether [`Command::allow_negative_numbers`] is set
+    pub fn is_allow_negative_numbers_set(&self) -> bool {
+        self.is_set(AppSettings::AllowNegativeNumbers)
+    }
+
+    /// Report whether [`Command::trailing_var_arg`] is set
+    pub fn is_trailing_var_arg_set(&self) -> bool {
+        self.is_set(AppSettings::TrailingVarArg)
+    }
+
+    /// Report whether [`Command::allow_missing_positional`] is set
+    pub fn is_allow_missing_positional_set(&self) -> bool {
+        self.is_set(AppSettings::AllowMissingPositional)
+    }
+
+    /// Report whether [`Command::hide`] is set
+    pub fn is_hide_set(&self) -> bool {
+        self.is_set(AppSettings::Hidden)
+    }
+
+    /// Report whether [`Command::subcommand_required`] is set
+    pub fn is_subcommand_required_set(&self) -> bool {
+        self.is_set(AppSettings::SubcommandRequired)
+    }
+
+    /// Report whether [`Command::allow_external_subcommands`] is set
+    pub fn is_allow_external_subcommands_set(&self) -> bool {
+        self.is_set(AppSettings::AllowExternalSubcommands)
+    }
+
+    /// Report whether [`Command::allow_invalid_utf8_for_external_subcommands`] is set
+    pub fn is_allow_invalid_utf8_for_external_subcommands_set(&self) -> bool {
+        self.is_set(AppSettings::AllowInvalidUtf8ForExternalSubcommands)
+    }
+
+    /// Configured parser for values passed to an external subcommand
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// let cmd = clap::Command::new("raw")
+    ///     .allow_external_subcommands(true)
+    ///     .allow_invalid_utf8_for_external_subcommands(true);
+    /// let value_parser = cmd.get_external_subcommand_value_parser();
+    /// println!("{:?}", value_parser);
+    /// ```
+    pub fn get_external_subcommand_value_parser(&self) -> Option<&super::ValueParser> {
+        if !self.is_allow_external_subcommands_set() {
+            None
+        } else if self.is_allow_invalid_utf8_for_external_subcommands_set() {
+            static DEFAULT: super::ValueParser = super::ValueParser::os_string();
+            Some(&DEFAULT)
+        } else {
+            static DEFAULT: super::ValueParser = super::ValueParser::string();
+            Some(&DEFAULT)
+        }
+    }
+
+    /// Report whether [`Command::args_conflicts_with_subcommands`] is set
+    pub fn is_args_conflicts_with_subcommands_set(&self) -> bool {
+        self.is_set(AppSettings::ArgsNegateSubcommands)
+    }
+
+    /// Report whether [`Command::subcommand_precedence_over_arg`] is set
+    pub fn is_subcommand_precedence_over_arg_set(&self) -> bool {
+        self.is_set(AppSettings::SubcommandPrecedenceOverArg)
+    }
+
+    /// Report whether [`Command::subcommand_negates_reqs`] is set
+    pub fn is_subcommand_negates_reqs_set(&self) -> bool {
+        self.is_set(AppSettings::SubcommandsNegateReqs)
+    }
+
+    /// Report whether [`Command::multicall`] is set
+    pub fn is_multicall_set(&self) -> bool {
+        self.is_set(AppSettings::Multicall)
+    }
+}
+
+/// Deprecated
+impl<'help> App<'help> {
+    /// Deprecated in [Issue #3087](https://github.com/clap-rs/clap/issues/3087), maybe [`clap::Parser`][crate::Parser] would fit your use case?
+    #[cfg(feature = "yaml")]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Deprecated in Issue #3087, maybe clap::Parser would fit your use case?"
+        )
+    )]
+    #[doc(hidden)]
+    pub fn from_yaml(y: &'help Yaml) -> Self {
+        #![allow(deprecated)]
+        let yaml_file_hash = y.as_hash().expect("YAML file must be a hash");
+        // We WANT this to panic on error...so expect() is good.
+        let (mut a, yaml, err) = if let Some(name) = y["name"].as_str() {
+            (App::new(name), yaml_file_hash, "cmd".into())
+        } else {
+            let (name_yaml, value_yaml) = yaml_file_hash
+                .iter()
+                .next()
+                .expect("There must be one subcommand in the YAML file");
+            let name_str = name_yaml
+                .as_str()
+                .expect("Subcommand name must be a string");
+
+            (
+                App::new(name_str),
+                value_yaml.as_hash().expect("Subcommand must be a hash"),
+                format!("subcommand '{}'", name_str),
+            )
+        };
+
+        for (k, v) in yaml {
+            a = match k.as_str().expect("App fields must be strings") {
+                "version" => yaml_to_str!(a, v, version),
+                "long_version" => yaml_to_str!(a, v, long_version),
+                "author" => yaml_to_str!(a, v, author),
+                "bin_name" => yaml_to_str!(a, v, bin_name),
+                "about" => yaml_to_str!(a, v, about),
+                "long_about" => yaml_to_str!(a, v, long_about),
+                "before_help" => yaml_to_str!(a, v, before_help),
+                "after_help" => yaml_to_str!(a, v, after_help),
+                "template" => yaml_to_str!(a, v, help_template),
+                "usage" => yaml_to_str!(a, v, override_usage),
+                "help" => yaml_to_str!(a, v, override_help),
+                "help_message" => yaml_to_str!(a, v, help_message),
+                "version_message" => yaml_to_str!(a, v, version_message),
+                "alias" => yaml_to_str!(a, v, alias),
+                "aliases" => yaml_vec_or_str!(a, v, alias),
+                "visible_alias" => yaml_to_str!(a, v, visible_alias),
+                "visible_aliases" => yaml_vec_or_str!(a, v, visible_alias),
+                "display_order" => yaml_to_usize!(a, v, display_order),
+                "args" => {
+                    if let Some(vec) = v.as_vec() {
+                        for arg_yaml in vec {
+                            a = a.arg(Arg::from_yaml(arg_yaml));
+                        }
+                    } else {
+                        panic!("Failed to convert YAML value {:?} to a vec", v);
+                    }
+                    a
+                }
+                "subcommands" => {
+                    if let Some(vec) = v.as_vec() {
+                        for sc_yaml in vec {
+                            a = a.subcommand(App::from_yaml(sc_yaml));
+                        }
+                    } else {
+                        panic!("Failed to convert YAML value {:?} to a vec", v);
+                    }
+                    a
+                }
+                "groups" => {
+                    if let Some(vec) = v.as_vec() {
+                        for ag_yaml in vec {
+                            a = a.group(ArgGroup::from(ag_yaml));
+                        }
+                    } else {
+                        panic!("Failed to convert YAML value {:?} to a vec", v);
+                    }
+                    a
+                }
+                "setting" | "settings" => {
+                    yaml_to_setting!(a, v, setting, AppSettings, "AppSetting", err)
+                }
+                "global_setting" | "global_settings" => {
+                    yaml_to_setting!(a, v, global_setting, AppSettings, "AppSetting", err)
+                }
+                _ => a,
+            }
+        }
+
+        a
+    }
+
+    /// Deprecated, replaced with [`Command::override_usage`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::override_usage`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn usage<S: Into<&'help str>>(self, usage: S) -> Self {
+        self.override_usage(usage)
+    }
+
+    /// Deprecated, replaced with [`Command::override_help`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::override_help`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn help<S: Into<&'help str>>(self, help: S) -> Self {
+        self.override_help(help)
+    }
+
+    /// Deprecated, replaced with [`Command::mut_arg`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::mut_arg`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn help_short(self, c: char) -> Self {
+        self.mut_arg("help", |a| a.short(c))
+    }
+
+    /// Deprecated, replaced with [`Command::mut_arg`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::mut_arg`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn version_short(self, c: char) -> Self {
+        self.mut_arg("version", |a| a.short(c))
+    }
+
+    /// Deprecated, replaced with [`Command::mut_arg`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::mut_arg`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn help_message(self, s: impl Into<&'help str>) -> Self {
+        self.mut_arg("help", |a| a.help(s.into()))
+    }
+
+    /// Deprecated, replaced with [`Command::mut_arg`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::mut_arg`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn version_message(self, s: impl Into<&'help str>) -> Self {
+        self.mut_arg("version", |a| a.help(s.into()))
+    }
+
+    /// Deprecated, replaced with [`Command::help_template`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::help_template`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn template<S: Into<&'help str>>(self, s: S) -> Self {
+        self.help_template(s)
+    }
+
+    /// Deprecated, replaced with [`Command::setting(a| b)`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::setting(a | b)`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn settings(mut self, settings: &[AppSettings]) -> Self {
+        for s in settings {
+            self.settings.insert((*s).into());
+        }
+        self
+    }
+
+    /// Deprecated, replaced with [`Command::unset_setting(a| b)`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::unset_setting(a | b)`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn unset_settings(mut self, settings: &[AppSettings]) -> Self {
+        for s in settings {
+            self.settings.remove((*s).into());
+        }
+        self
+    }
+
+    /// Deprecated, replaced with [`Command::global_setting(a| b)`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::global_setting(a | b)`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn global_settings(mut self, settings: &[AppSettings]) -> Self {
+        for s in settings {
+            self.settings.insert((*s).into());
+            self.g_settings.insert((*s).into());
+        }
+        self
+    }
+
+    /// Deprecated, replaced with [`Command::term_width`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::term_width`")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn set_term_width(self, width: usize) -> Self {
+        self.term_width(width)
+    }
+
+    /// Deprecated in [Issue #3086](https://github.com/clap-rs/clap/issues/3086), see [`arg!`][crate::arg!].
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Deprecated in Issue #3086, see `clap::arg!")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn arg_from_usage(self, usage: &'help str) -> Self {
+        #![allow(deprecated)]
+        self.arg(Arg::from_usage(usage))
+    }
+
+    /// Deprecated in [Issue #3086](https://github.com/clap-rs/clap/issues/3086), see [`arg!`][crate::arg!].
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Deprecated in Issue #3086, see `clap::arg!")
+    )]
+    #[doc(hidden)]
+    #[must_use]
+    pub fn args_from_usage(mut self, usage: &'help str) -> Self {
+        #![allow(deprecated)]
+        for line in usage.lines() {
+            let l = line.trim();
+            if l.is_empty() {
+                continue;
+            }
+            self = self.arg(Arg::from_usage(l));
+        }
+        self
+    }
+
+    /// Deprecated, replaced with [`Command::render_version`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::render_version`")
+    )]
+    #[doc(hidden)]
+    pub fn write_version<W: io::Write>(&self, w: &mut W) -> ClapResult<()> {
+        write!(w, "{}", self.render_version()).map_err(From::from)
+    }
+
+    /// Deprecated, replaced with [`Command::render_long_version`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::render_long_version`")
+    )]
+    #[doc(hidden)]
+    pub fn write_long_version<W: io::Write>(&self, w: &mut W) -> ClapResult<()> {
+        write!(w, "{}", self.render_long_version()).map_err(From::from)
+    }
+
+    /// Deprecated, replaced with [`Command::try_get_matches`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::try_get_matches`")
+    )]
+    #[doc(hidden)]
+    pub fn get_matches_safe(self) -> ClapResult<ArgMatches> {
+        self.try_get_matches()
+    }
+
+    /// Deprecated, replaced with [`Command::try_get_matches_from`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `App::try_get_matches_from`")
+    )]
+    #[doc(hidden)]
+    pub fn get_matches_from_safe<I, T>(self, itr: I) -> ClapResult<ArgMatches>
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        self.try_get_matches_from(itr)
+    }
+
+    /// Deprecated, replaced with [`Command::try_get_matches_from_mut`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Replaced with `App::try_get_matches_from_mut`"
+        )
+    )]
+    #[doc(hidden)]
+    pub fn get_matches_from_safe_borrow<I, T>(&mut self, itr: I) -> ClapResult<ArgMatches>
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        self.try_get_matches_from_mut(itr)
+    }
+}
+
+// Internally used only
+impl<'help> App<'help> {
+    pub(crate) fn get_id(&self) -> Id {
+        self.id.clone()
+    }
+
+    pub(crate) fn get_override_usage(&self) -> Option<&str> {
+        self.usage_str
+    }
+
+    pub(crate) fn get_override_help(&self) -> Option<&str> {
+        self.help_str
+    }
+
+    pub(crate) fn get_help_template(&self) -> Option<&str> {
+        self.template
+    }
+
+    pub(crate) fn get_term_width(&self) -> Option<usize> {
+        self.term_w
+    }
+
+    pub(crate) fn get_max_term_width(&self) -> Option<usize> {
+        self.max_w
+    }
+
+    pub(crate) fn get_replacement(&self, key: &str) -> Option<&[&str]> {
+        self.replacers.get(key).copied()
+    }
+
+    pub(crate) fn get_keymap(&self) -> &MKeyMap<'help> {
+        &self.args
+    }
+
+    fn get_used_global_args(&self, matches: &ArgMatches, global_arg_vec: &mut Vec<Id>) {
+        global_arg_vec.extend(
+            self.args
+                .args()
+                .filter(|a| a.is_global_set())
+                .map(|ga| ga.id.clone()),
+        );
+        if let Some((id, matches)) = matches.subcommand() {
+            if let Some(used_sub) = self.find_subcommand(id) {
+                used_sub.get_used_global_args(matches, global_arg_vec);
+            }
+        }
+    }
+
+    fn _do_parse(
+        &mut self,
+        raw_args: &mut clap_lex::RawArgs,
+        args_cursor: clap_lex::ArgCursor,
+    ) -> ClapResult<ArgMatches> {
+        debug!("Command::_do_parse");
+
+        // If there are global arguments, or settings we need to propagate them down to subcommands
+        // before parsing in case we run into a subcommand
+        self._build_self();
+
+        let mut matcher = ArgMatcher::new(self);
+
+        // do the real parsing
+        let mut parser = Parser::new(self);
+        if let Err(error) = parser.get_matches_with(&mut matcher, raw_args, args_cursor) {
+            if self.is_set(AppSettings::IgnoreErrors) {
+                debug!("Command::_do_parse: ignoring error: {}", error);
+            } else {
+                return Err(error);
+            }
+        }
+
+        let mut global_arg_vec = Default::default();
+        self.get_used_global_args(&matcher, &mut global_arg_vec);
+
+        matcher.propagate_globals(&global_arg_vec);
+
+        Ok(matcher.into_inner())
+    }
+
+    #[doc(hidden)]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.10", note = "Replaced with `Command::build`")
+    )]
+    pub fn _build_all(&mut self) {
+        self.build();
+    }
+
+    #[doc(hidden)]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.10", note = "Replaced with `Command::build`")
+    )]
+    pub fn _build(&mut self) {
+        self._build_self()
+    }
+
+    #[doc(hidden)]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.13", note = "Replaced with `Command::build`")
+    )]
+    pub fn _build_bin_names(&mut self) {
+        self._build_bin_names_internal();
+    }
+
+    /// Prepare for introspecting on all included [`Command`]s
+    ///
+    /// Call this on the top-level [`Command`] when done building and before reading state for
+    /// cases like completions, custom help output, etc.
+    pub fn build(&mut self) {
+        self._build_recursive();
+        self._build_bin_names_internal();
+    }
+
+    pub(crate) fn _build_recursive(&mut self) {
+        self._build_self();
+        for subcmd in self.get_subcommands_mut() {
+            subcmd._build_recursive();
+        }
+    }
+
+    pub(crate) fn _build_self(&mut self) {
+        debug!("Command::_build: name={:?}", self.get_name());
+        if !self.settings.is_set(AppSettings::Built) {
+            // Make sure all the globally set flags apply to us as well
+            self.settings = self.settings | self.g_settings;
+
+            if self.is_multicall_set() {
+                self.settings.insert(AppSettings::SubcommandRequired.into());
+                self.settings.insert(AppSettings::DisableHelpFlag.into());
+                self.settings.insert(AppSettings::DisableVersionFlag.into());
+            }
+
+            self._propagate();
+            self._check_help_and_version();
+            self._propagate_global_args();
+            self._derive_display_order();
+
+            let mut pos_counter = 1;
+            let self_override = self.is_set(AppSettings::AllArgsOverrideSelf);
+            let hide_pv = self.is_set(AppSettings::HidePossibleValues);
+            let auto_help =
+                !self.is_set(AppSettings::NoAutoHelp) && !self.is_disable_help_flag_set();
+            let auto_version =
+                !self.is_set(AppSettings::NoAutoVersion) && !self.is_disable_version_flag_set();
+            for a in self.args.args_mut() {
+                // Fill in the groups
+                for g in &a.groups {
+                    if let Some(ag) = self.groups.iter_mut().find(|grp| grp.id == *g) {
+                        ag.args.push(a.id.clone());
+                    } else {
+                        let mut ag = ArgGroup::with_id(g.clone());
+                        ag.args.push(a.id.clone());
+                        self.groups.push(ag);
+                    }
+                }
+
+                // Figure out implied settings
+                if a.is_last_set() {
+                    // if an arg has `Last` set, we need to imply DontCollapseArgsInUsage so that args
+                    // in the usage string don't get confused or left out.
+                    self.settings.set(AppSettings::DontCollapseArgsInUsage);
+                }
+                if hide_pv && a.is_takes_value_set() {
+                    a.settings.set(ArgSettings::HidePossibleValues);
+                }
+                if self_override {
+                    let self_id = a.id.clone();
+                    a.overrides.push(self_id);
+                }
+                a._build();
+                // HACK: Setting up action at this level while auto-help / disable help flag is
+                // required.  Otherwise, most of this won't be needed because when we can break
+                // compat, actions will reign supreme (default to `Store`)
+                if a.action.is_none() {
+                    if a.get_id() == "help" && auto_help && !a.is_takes_value_set() {
+                        let action = super::ArgAction::Help;
+                        a.action = Some(action);
+                    } else if a.get_id() == "version" && auto_version && !a.is_takes_value_set() {
+                        let action = super::ArgAction::Version;
+                        a.action = Some(action);
+                    } else if a.is_takes_value_set() {
+                        let action = super::ArgAction::StoreValue;
+                        a.action = Some(action);
+                    } else {
+                        let action = super::ArgAction::IncOccurrence;
+                        a.action = Some(action);
+                    }
+                }
+                if a.is_positional() && a.index.is_none() {
+                    a.index = Some(pos_counter);
+                    pos_counter += 1;
+                }
+            }
+
+            self.args._build();
+
+            #[cfg(debug_assertions)]
+            assert_app(self);
+            self.settings.set(AppSettings::Built);
+        } else {
+            debug!("Command::_build: already built");
+        }
+    }
+
+    pub(crate) fn _build_subcommand(&mut self, name: &str) -> Option<&mut Self> {
+        use std::fmt::Write;
+
+        let mut mid_string = String::from(" ");
+        if !self.is_subcommand_negates_reqs_set() && !self.is_args_conflicts_with_subcommands_set()
+        {
+            let reqs = Usage::new(self).get_required_usage_from(&[], None, true); // maybe Some(m)
+
+            for s in &reqs {
+                mid_string.push_str(s);
+                mid_string.push(' ');
+            }
+        }
+        let is_multicall_set = self.is_multicall_set();
+
+        let sc = self.subcommands.iter_mut().find(|s| s.name == name)?;
+
+        // Display subcommand name, short and long in usage
+        let mut sc_names = sc.name.clone();
+        let mut flag_subcmd = false;
+        if let Some(l) = sc.long_flag {
+            write!(sc_names, "|--{}", l).unwrap();
+            flag_subcmd = true;
+        }
+        if let Some(s) = sc.short_flag {
+            write!(sc_names, "|-{}", s).unwrap();
+            flag_subcmd = true;
+        }
+
+        if flag_subcmd {
+            sc_names = format!("{{{}}}", sc_names);
+        }
+
+        let usage_name = self
+            .bin_name
+            .as_ref()
+            .map(|bin_name| format!("{}{}{}", bin_name, mid_string, sc_names))
+            .unwrap_or(sc_names);
+        sc.usage_name = Some(usage_name);
+
+        // bin_name should be parent's bin_name + [<reqs>] + the sc's name separated by
+        // a space
+        let bin_name = format!(
+            "{}{}{}",
+            self.bin_name.as_ref().unwrap_or(&String::new()),
+            if self.bin_name.is_some() { " " } else { "" },
+            &*sc.name
+        );
+        debug!(
+            "Command::_build_subcommand Setting bin_name of {} to {:?}",
+            sc.name, bin_name
+        );
+        sc.bin_name = Some(bin_name);
+
+        if sc.display_name.is_none() {
+            let self_display_name = if is_multicall_set {
+                self.display_name.as_deref().unwrap_or("")
+            } else {
+                self.display_name.as_deref().unwrap_or(&self.name)
+            };
+            let display_name = format!(
+                "{}{}{}",
+                self_display_name,
+                if !self_display_name.is_empty() {
+                    "-"
+                } else {
+                    ""
+                },
+                &*sc.name
+            );
+            debug!(
+                "Command::_build_subcommand Setting display_name of {} to {:?}",
+                sc.name, display_name
+            );
+            sc.display_name = Some(display_name);
+        }
+
+        // Ensure all args are built and ready to parse
+        sc._build_self();
+
+        Some(sc)
+    }
+
+    fn _build_bin_names_internal(&mut self) {
+        debug!("Command::_build_bin_names");
+
+        if !self.is_set(AppSettings::BinNameBuilt) {
+            let mut mid_string = String::from(" ");
+            if !self.is_subcommand_negates_reqs_set()
+                && !self.is_args_conflicts_with_subcommands_set()
+            {
+                let reqs = Usage::new(self).get_required_usage_from(&[], None, true); // maybe Some(m)
+
+                for s in &reqs {
+                    mid_string.push_str(s);
+                    mid_string.push(' ');
+                }
+            }
+            let is_multicall_set = self.is_multicall_set();
+
+            let self_bin_name = if is_multicall_set {
+                self.bin_name.as_deref().unwrap_or("")
+            } else {
+                self.bin_name.as_deref().unwrap_or(&self.name)
+            }
+            .to_owned();
+
+            for mut sc in &mut self.subcommands {
+                debug!("Command::_build_bin_names:iter: bin_name set...");
+
+                if sc.usage_name.is_none() {
+                    use std::fmt::Write;
+                    // Display subcommand name, short and long in usage
+                    let mut sc_names = sc.name.clone();
+                    let mut flag_subcmd = false;
+                    if let Some(l) = sc.long_flag {
+                        write!(sc_names, "|--{}", l).unwrap();
+                        flag_subcmd = true;
+                    }
+                    if let Some(s) = sc.short_flag {
+                        write!(sc_names, "|-{}", s).unwrap();
+                        flag_subcmd = true;
+                    }
+
+                    if flag_subcmd {
+                        sc_names = format!("{{{}}}", sc_names);
+                    }
+
+                    let usage_name = format!("{}{}{}", self_bin_name, mid_string, sc_names);
+                    debug!(
+                        "Command::_build_bin_names:iter: Setting usage_name of {} to {:?}",
+                        sc.name, usage_name
+                    );
+                    sc.usage_name = Some(usage_name);
+                } else {
+                    debug!(
+                        "Command::_build_bin_names::iter: Using existing usage_name of {} ({:?})",
+                        sc.name, sc.usage_name
+                    );
+                }
+
+                if sc.bin_name.is_none() {
+                    let bin_name = format!(
+                        "{}{}{}",
+                        self_bin_name,
+                        if !self_bin_name.is_empty() { " " } else { "" },
+                        &*sc.name
+                    );
+                    debug!(
+                        "Command::_build_bin_names:iter: Setting bin_name of {} to {:?}",
+                        sc.name, bin_name
+                    );
+                    sc.bin_name = Some(bin_name);
+                } else {
+                    debug!(
+                        "Command::_build_bin_names::iter: Using existing bin_name of {} ({:?})",
+                        sc.name, sc.bin_name
+                    );
+                }
+
+                if sc.display_name.is_none() {
+                    let self_display_name = if is_multicall_set {
+                        self.display_name.as_deref().unwrap_or("")
+                    } else {
+                        self.display_name.as_deref().unwrap_or(&self.name)
+                    };
+                    let display_name = format!(
+                        "{}{}{}",
+                        self_display_name,
+                        if !self_display_name.is_empty() {
+                            "-"
+                        } else {
+                            ""
+                        },
+                        &*sc.name
+                    );
+                    debug!(
+                        "Command::_build_bin_names:iter: Setting display_name of {} to {:?}",
+                        sc.name, display_name
+                    );
+                    sc.display_name = Some(display_name);
+                } else {
+                    debug!(
+                        "Command::_build_bin_names::iter: Using existing display_name of {} ({:?})",
+                        sc.name, sc.display_name
+                    );
+                }
+
+                sc._build_bin_names_internal();
+            }
+            self.set(AppSettings::BinNameBuilt);
+        } else {
+            debug!("Command::_build_bin_names: already built");
+        }
+    }
+
+    pub(crate) fn _panic_on_missing_help(&self, help_required_globally: bool) {
+        if self.is_set(AppSettings::HelpExpected) || help_required_globally {
+            let args_missing_help: Vec<String> = self
+                .args
+                .args()
+                .filter(|arg| arg.help.is_none() && arg.long_help.is_none())
+                .map(|arg| String::from(arg.name))
+                .collect();
+
+            assert!(args_missing_help.is_empty(),
+                    "Command::help_expected is enabled for the Command {}, but at least one of its arguments does not have either `help` or `long_help` set. List of such arguments: {}",
+                    self.name,
+                    args_missing_help.join(", ")
+                );
+        }
+
+        for sub_app in &self.subcommands {
+            sub_app._panic_on_missing_help(help_required_globally);
+        }
+    }
+
+    #[cfg(debug_assertions)]
+    pub(crate) fn two_args_of<F>(&self, condition: F) -> Option<(&Arg<'help>, &Arg<'help>)>
+    where
+        F: Fn(&Arg) -> bool,
+    {
+        two_elements_of(self.args.args().filter(|a: &&Arg| condition(a)))
+    }
+
+    // just in case
+    #[allow(unused)]
+    fn two_groups_of<F>(&self, condition: F) -> Option<(&ArgGroup, &ArgGroup)>
+    where
+        F: Fn(&ArgGroup) -> bool,
+    {
+        two_elements_of(self.groups.iter().filter(|a| condition(a)))
+    }
+
+    /// Propagate global args
+    pub(crate) fn _propagate_global_args(&mut self) {
+        debug!("Command::_propagate_global_args:{}", self.name);
+
+        for sc in &mut self.subcommands {
+            for a in self.args.args().filter(|a| a.is_global_set()) {
+                let mut propagate = false;
+                let is_generated = matches!(
+                    a.provider,
+                    ArgProvider::Generated | ArgProvider::GeneratedMutated
+                );
+
+                // Remove generated help and version args in the subcommand
+                //
+                // Don't remove if those args are further mutated
+                if is_generated {
+                    let generated_pos = sc
+                        .args
+                        .args()
+                        .position(|x| x.id == a.id && x.provider == ArgProvider::Generated);
+
+                    if let Some(index) = generated_pos {
+                        debug!(
+                            "Command::_propagate removing {}'s {:?}",
+                            sc.get_name(),
+                            a.id
+                        );
+                        sc.args.remove(index);
+                        propagate = true;
+                    }
+                }
+
+                if propagate || sc.find(&a.id).is_none() {
+                    debug!(
+                        "Command::_propagate pushing {:?} to {}",
+                        a.id,
+                        sc.get_name(),
+                    );
+                    sc.args.push(a.clone());
+                }
+            }
+        }
+    }
+
+    /// Propagate settings
+    pub(crate) fn _propagate(&mut self) {
+        debug!("Command::_propagate:{}", self.name);
+        let mut subcommands = std::mem::take(&mut self.subcommands);
+        for sc in &mut subcommands {
+            self._propagate_subcommand(sc);
+        }
+        self.subcommands = subcommands;
+    }
+
+    fn _propagate_subcommand(&self, sc: &mut Self) {
+        // We have to create a new scope in order to tell rustc the borrow of `sc` is
+        // done and to recursively call this method
+        {
+            if self.settings.is_set(AppSettings::PropagateVersion) {
+                if sc.version.is_none() && self.version.is_some() {
+                    sc.version = Some(self.version.unwrap());
+                }
+                if sc.long_version.is_none() && self.long_version.is_some() {
+                    sc.long_version = Some(self.long_version.unwrap());
+                }
+            }
+
+            sc.settings = sc.settings | self.g_settings;
+            sc.g_settings = sc.g_settings | self.g_settings;
+            sc.term_w = self.term_w;
+            sc.max_w = self.max_w;
+        }
+    }
+
+    #[allow(clippy::blocks_in_if_conditions)]
+    pub(crate) fn _check_help_and_version(&mut self) {
+        debug!("Command::_check_help_and_version: {}", self.name);
+
+        if self.is_set(AppSettings::DisableHelpFlag)
+            || self.args.args().any(|x| {
+                x.provider == ArgProvider::User
+                    && (x.long == Some("help") || x.id == Id::help_hash())
+            })
+            || self
+                .subcommands
+                .iter()
+                .any(|sc| sc.long_flag == Some("help"))
+        {
+            debug!("Command::_check_help_and_version: Removing generated help");
+
+            let generated_help_pos = self
+                .args
+                .args()
+                .position(|x| x.id == Id::help_hash() && x.provider == ArgProvider::Generated);
+
+            if let Some(index) = generated_help_pos {
+                self.args.remove(index);
+            }
+        } else {
+            let help = self
+                .args
+                .args()
+                .find(|x| x.id == Id::help_hash())
+                .expect(INTERNAL_ERROR_MSG);
+            assert_ne!(help.provider, ArgProvider::User);
+
+            if help.short.is_some() {
+                if help.short == Some('h') {
+                    if let Some(other_arg) = self
+                        .args
+                        .args()
+                        .find(|x| x.id != Id::help_hash() && x.short == Some('h'))
+                    {
+                        panic!(
+                            "`help`s `-h` conflicts with `{}`.
+
+To change `help`s short, call `cmd.arg(Arg::new(\"help\")...)`.",
+                            other_arg.name
+                        );
+                    }
+                }
+            } else if !(self.args.args().any(|x| x.short == Some('h'))
+                || self.subcommands.iter().any(|sc| sc.short_flag == Some('h')))
+            {
+                let help = self
+                    .args
+                    .args_mut()
+                    .find(|x| x.id == Id::help_hash())
+                    .expect(INTERNAL_ERROR_MSG);
+                help.short = Some('h');
+            } else {
+                debug!("Command::_check_help_and_version: Removing `-h` from help");
+            }
+        }
+
+        // Determine if we should remove the generated --version flag
+        //
+        // Note that if only mut_arg() was used, the first expression will evaluate to `true`
+        // however inside the condition block, we only check for Generated args, not
+        // GeneratedMutated args, so the `mut_arg("version", ..) will be skipped and fall through
+        // to the following condition below (Adding the short `-V`)
+        if self.settings.is_set(AppSettings::DisableVersionFlag)
+            || (self.version.is_none() && self.long_version.is_none())
+            || self.args.args().any(|x| {
+                x.provider == ArgProvider::User
+                    && (x.long == Some("version") || x.id == Id::version_hash())
+            })
+            || self
+                .subcommands
+                .iter()
+                .any(|sc| sc.long_flag == Some("version"))
+        {
+            debug!("Command::_check_help_and_version: Removing generated version");
+
+            // This is the check mentioned above that only checks for Generated, not
+            // GeneratedMutated args by design.
+            let generated_version_pos = self
+                .args
+                .args()
+                .position(|x| x.id == Id::version_hash() && x.provider == ArgProvider::Generated);
+
+            if let Some(index) = generated_version_pos {
+                self.args.remove(index);
+            }
+        }
+
+        // If we still have a generated --version flag, determine if we can apply the short `-V`
+        if self.args.args().any(|x| {
+            x.id == Id::version_hash()
+                && matches!(
+                    x.provider,
+                    ArgProvider::Generated | ArgProvider::GeneratedMutated
+                )
+        }) {
+            let other_arg_has_short = self.args.args().any(|x| x.short == Some('V'));
+            let version = self
+                .args
+                .args_mut()
+                .find(|x| x.id == Id::version_hash())
+                .expect(INTERNAL_ERROR_MSG);
+
+            if !(version.short.is_some()
+                || other_arg_has_short
+                || self.subcommands.iter().any(|sc| sc.short_flag == Some('V')))
+            {
+                version.short = Some('V');
+            }
+        }
+
+        if !self.is_set(AppSettings::DisableHelpSubcommand)
+            && self.has_subcommands()
+            && !self.subcommands.iter().any(|s| s.id == Id::help_hash())
+        {
+            debug!("Command::_check_help_and_version: Building help subcommand");
+            let mut help_subcmd = App::new("help")
+                .about("Print this message or the help of the given subcommand(s)")
+                .arg(
+                    Arg::new("subcommand")
+                        .index(1)
+                        .takes_value(true)
+                        .multiple_occurrences(true)
+                        .value_name("SUBCOMMAND")
+                        .help("The subcommand whose help message to display"),
+                );
+            self._propagate_subcommand(&mut help_subcmd);
+
+            // The parser acts like this is set, so let's set it so we don't falsely
+            // advertise it to the user
+            help_subcmd.version = None;
+            help_subcmd.long_version = None;
+            help_subcmd = help_subcmd
+                .setting(AppSettings::DisableHelpFlag)
+                .unset_global_setting(AppSettings::PropagateVersion);
+
+            self.subcommands.push(help_subcmd);
+        }
+    }
+
+    pub(crate) fn _derive_display_order(&mut self) {
+        debug!("Command::_derive_display_order:{}", self.name);
+
+        if self.settings.is_set(AppSettings::DeriveDisplayOrder) {
+            for a in self
+                .args
+                .args_mut()
+                .filter(|a| !a.is_positional())
+                .filter(|a| a.provider != ArgProvider::Generated)
+            {
+                a.disp_ord.make_explicit();
+            }
+            for (i, sc) in &mut self.subcommands.iter_mut().enumerate() {
+                sc.disp_ord.get_or_insert(i);
+            }
+        }
+        for sc in &mut self.subcommands {
+            sc._derive_display_order();
+        }
+    }
+
+    pub(crate) fn _render_version(&self, use_long: bool) -> String {
+        debug!("Command::_render_version");
+
+        let ver = if use_long {
+            self.long_version.or(self.version).unwrap_or("")
+        } else {
+            self.version.or(self.long_version).unwrap_or("")
+        };
+        if let Some(bn) = self.bin_name.as_ref() {
+            if bn.contains(' ') {
+                // In case we're dealing with subcommands i.e. git mv is translated to git-mv
+                format!("{} {}\n", bn.replace(' ', "-"), ver)
+            } else {
+                format!("{} {}\n", &self.name[..], ver)
+            }
+        } else {
+            format!("{} {}\n", &self.name[..], ver)
+        }
+    }
+
+    pub(crate) fn format_group(&self, g: &Id) -> String {
+        let g_string = self
+            .unroll_args_in_group(g)
+            .iter()
+            .filter_map(|x| self.find(x))
+            .map(|x| {
+                if x.is_positional() {
+                    // Print val_name for positional arguments. e.g. <file_name>
+                    x.name_no_brackets().to_string()
+                } else {
+                    // Print usage string for flags arguments, e.g. <--help>
+                    x.to_string()
+                }
+            })
+            .collect::<Vec<_>>()
+            .join("|");
+        format!("<{}>", &*g_string)
+    }
+}
+
+/// A workaround:
+/// <https://github.com/rust-lang/rust/issues/34511#issuecomment-373423999>
+pub(crate) trait Captures<'a> {}
+impl<'a, T> Captures<'a> for T {}
+
+// Internal Query Methods
+impl<'help> App<'help> {
+    /// Iterate through the *flags* & *options* arguments.
+    pub(crate) fn get_non_positionals(&self) -> impl Iterator<Item = &Arg<'help>> {
+        self.get_arguments().filter(|a| !a.is_positional())
+    }
+
+    /// Iterate through the *positionals* that don't have custom heading.
+    pub(crate) fn get_positionals_with_no_heading(&self) -> impl Iterator<Item = &Arg<'help>> {
+        self.get_positionals()
+            .filter(|a| a.get_help_heading().is_none())
+    }
+
+    /// Iterate through the *flags* & *options* that don't have custom heading.
+    pub(crate) fn get_non_positionals_with_no_heading(&self) -> impl Iterator<Item = &Arg<'help>> {
+        self.get_non_positionals()
+            .filter(|a| a.get_help_heading().is_none())
+    }
+
+    pub(crate) fn find(&self, arg_id: &Id) -> Option<&Arg<'help>> {
+        self.args.args().find(|a| a.id == *arg_id)
+    }
+
+    #[inline]
+    pub(crate) fn contains_short(&self, s: char) -> bool {
+        assert!(
+            self.is_set(AppSettings::Built),
+            "If App::_build hasn't been called, manually search through Arg shorts"
+        );
+
+        self.args.contains(s)
+    }
+
+    #[inline]
+    pub(crate) fn set(&mut self, s: AppSettings) {
+        self.settings.set(s)
+    }
+
+    #[inline]
+    pub(crate) fn has_args(&self) -> bool {
+        !self.args.is_empty()
+    }
+
+    pub(crate) fn has_positionals(&self) -> bool {
+        self.args.keys().any(|x| x.is_position())
+    }
+
+    pub(crate) fn has_visible_subcommands(&self) -> bool {
+        self.subcommands
+            .iter()
+            .any(|sc| sc.name != "help" && !sc.is_set(AppSettings::Hidden))
+    }
+
+    /// Check if this subcommand can be referred to as `name`. In other words,
+    /// check if `name` is the name of this subcommand or is one of its aliases.
+    #[inline]
+    pub(crate) fn aliases_to<T>(&self, name: &T) -> bool
+    where
+        T: PartialEq<str> + ?Sized,
+    {
+        *name == *self.get_name() || self.get_all_aliases().any(|alias| *name == *alias)
+    }
+
+    /// Check if this subcommand can be referred to as `name`. In other words,
+    /// check if `name` is the name of this short flag subcommand or is one of its short flag aliases.
+    #[inline]
+    pub(crate) fn short_flag_aliases_to(&self, flag: char) -> bool {
+        Some(flag) == self.short_flag
+            || self.get_all_short_flag_aliases().any(|alias| flag == alias)
+    }
+
+    /// Check if this subcommand can be referred to as `name`. In other words,
+    /// check if `name` is the name of this long flag subcommand or is one of its long flag aliases.
+    #[inline]
+    pub(crate) fn long_flag_aliases_to<T>(&self, flag: &T) -> bool
+    where
+        T: PartialEq<str> + ?Sized,
+    {
+        match self.long_flag {
+            Some(long_flag) => {
+                flag == long_flag || self.get_all_long_flag_aliases().any(|alias| flag == alias)
+            }
+            None => self.get_all_long_flag_aliases().any(|alias| flag == alias),
+        }
+    }
+
+    #[cfg(debug_assertions)]
+    pub(crate) fn id_exists(&self, id: &Id) -> bool {
+        self.args.args().any(|x| x.id == *id) || self.groups.iter().any(|x| x.id == *id)
+    }
+
+    /// Iterate through the groups this arg is member of.
+    pub(crate) fn groups_for_arg<'a>(&'a self, arg: &Id) -> impl Iterator<Item = Id> + 'a {
+        debug!("Command::groups_for_arg: id={:?}", arg);
+        let arg = arg.clone();
+        self.groups
+            .iter()
+            .filter(move |grp| grp.args.iter().any(|a| a == &arg))
+            .map(|grp| grp.id.clone())
+    }
+
+    pub(crate) fn find_group(&self, group_id: &Id) -> Option<&ArgGroup<'help>> {
+        self.groups.iter().find(|g| g.id == *group_id)
+    }
+
+    /// Iterate through all the names of all subcommands (not recursively), including aliases.
+    /// Used for suggestions.
+    pub(crate) fn all_subcommand_names(&self) -> impl Iterator<Item = &str> + Captures<'help> {
+        self.get_subcommands().flat_map(|sc| {
+            let name = sc.get_name();
+            let aliases = sc.get_all_aliases();
+            std::iter::once(name).chain(aliases)
+        })
+    }
+
+    pub(crate) fn required_graph(&self) -> ChildGraph<Id> {
+        let mut reqs = ChildGraph::with_capacity(5);
+        for a in self.args.args().filter(|a| a.is_required_set()) {
+            reqs.insert(a.id.clone());
+        }
+        for group in &self.groups {
+            if group.required {
+                let idx = reqs.insert(group.id.clone());
+                for a in &group.requires {
+                    reqs.insert_child(idx, a.clone());
+                }
+            }
+        }
+
+        reqs
+    }
+
+    pub(crate) fn unroll_args_in_group(&self, group: &Id) -> Vec<Id> {
+        debug!("Command::unroll_args_in_group: group={:?}", group);
+        let mut g_vec = vec![group];
+        let mut args = vec![];
+
+        while let Some(g) = g_vec.pop() {
+            for n in self
+                .groups
+                .iter()
+                .find(|grp| grp.id == *g)
+                .expect(INTERNAL_ERROR_MSG)
+                .args
+                .iter()
+            {
+                debug!("Command::unroll_args_in_group:iter: entity={:?}", n);
+                if !args.contains(n) {
+                    if self.find(n).is_some() {
+                        debug!("Command::unroll_args_in_group:iter: this is an arg");
+                        args.push(n.clone())
+                    } else {
+                        debug!("Command::unroll_args_in_group:iter: this is a group");
+                        g_vec.push(n);
+                    }
+                }
+            }
+        }
+
+        args
+    }
+
+    pub(crate) fn unroll_arg_requires<F>(&self, func: F, arg: &Id) -> Vec<Id>
+    where
+        F: Fn(&(ArgPredicate<'_>, Id)) -> Option<Id>,
+    {
+        let mut processed = vec![];
+        let mut r_vec = vec![arg];
+        let mut args = vec![];
+
+        while let Some(a) = r_vec.pop() {
+            if processed.contains(&a) {
+                continue;
+            }
+
+            processed.push(a);
+
+            if let Some(arg) = self.find(a) {
+                for r in arg.requires.iter().filter_map(&func) {
+                    if let Some(req) = self.find(&r) {
+                        if !req.requires.is_empty() {
+                            r_vec.push(&req.id)
+                        }
+                    }
+                    args.push(r);
+                }
+            }
+        }
+
+        args
+    }
+
+    /// Find a flag subcommand name by short flag or an alias
+    pub(crate) fn find_short_subcmd(&self, c: char) -> Option<&str> {
+        self.get_subcommands()
+            .find(|sc| sc.short_flag_aliases_to(c))
+            .map(|sc| sc.get_name())
+    }
+
+    /// Find a flag subcommand name by long flag or an alias
+    pub(crate) fn find_long_subcmd(&self, long: &str) -> Option<&str> {
+        self.get_subcommands()
+            .find(|sc| sc.long_flag_aliases_to(long))
+            .map(|sc| sc.get_name())
+    }
+
+    pub(crate) fn get_display_order(&self) -> usize {
+        self.disp_ord.unwrap_or(999)
+    }
+
+    pub(crate) fn write_help_err(
+        &self,
+        mut use_long: bool,
+        stream: Stream,
+    ) -> ClapResult<Colorizer> {
+        debug!(
+            "Parser::write_help_err: use_long={:?}, stream={:?}",
+            use_long && self.use_long_help(),
+            stream
+        );
+
+        use_long = use_long && self.use_long_help();
+        let usage = Usage::new(self);
+
+        let mut c = Colorizer::new(stream, self.color_help());
+        Help::new(HelpWriter::Buffer(&mut c), self, &usage, use_long).write_help()?;
+        Ok(c)
+    }
+
+    pub(crate) fn use_long_help(&self) -> bool {
+        debug!("Command::use_long_help");
+        // In this case, both must be checked. This allows the retention of
+        // original formatting, but also ensures that the actual -h or --help
+        // specified by the user is sent through. If hide_short_help is not included,
+        // then items specified with hidden_short_help will also be hidden.
+        let should_long = |v: &Arg| {
+            v.long_help.is_some()
+                || v.is_hide_long_help_set()
+                || v.is_hide_short_help_set()
+                || cfg!(feature = "unstable-v4")
+                    && v.get_possible_values2()
+                        .iter()
+                        .any(PossibleValue::should_show_help)
+        };
+
+        // Subcommands aren't checked because we prefer short help for them, deferring to
+        // `cmd subcmd --help` for more.
+        self.get_long_about().is_some()
+            || self.get_before_long_help().is_some()
+            || self.get_after_long_help().is_some()
+            || self.get_arguments().any(should_long)
+    }
+
+    // Should we color the help?
+    pub(crate) fn color_help(&self) -> ColorChoice {
+        #[cfg(feature = "color")]
+        if self.is_disable_colored_help_set() {
+            return ColorChoice::Never;
+        }
+
+        self.get_color()
+    }
+}
+
+impl<'help> Default for App<'help> {
+    fn default() -> Self {
+        Self {
+            id: Default::default(),
+            name: Default::default(),
+            long_flag: Default::default(),
+            short_flag: Default::default(),
+            display_name: Default::default(),
+            bin_name: Default::default(),
+            author: Default::default(),
+            version: Default::default(),
+            long_version: Default::default(),
+            about: Default::default(),
+            long_about: Default::default(),
+            before_help: Default::default(),
+            before_long_help: Default::default(),
+            after_help: Default::default(),
+            after_long_help: Default::default(),
+            aliases: Default::default(),
+            short_flag_aliases: Default::default(),
+            long_flag_aliases: Default::default(),
+            usage_str: Default::default(),
+            usage_name: Default::default(),
+            help_str: Default::default(),
+            disp_ord: Default::default(),
+            term_w: Default::default(),
+            max_w: Default::default(),
+            template: Default::default(),
+            settings: Default::default(),
+            g_settings: Default::default(),
+            args: Default::default(),
+            subcommands: Default::default(),
+            replacers: Default::default(),
+            groups: Default::default(),
+            current_help_heading: Default::default(),
+            current_disp_ord: Some(0),
+            subcommand_value_name: Default::default(),
+            subcommand_heading: Default::default(),
+        }
+    }
+}
+
+impl<'help> Index<&'_ Id> for App<'help> {
+    type Output = Arg<'help>;
+
+    fn index(&self, key: &Id) -> &Self::Output {
+        self.find(key).expect(INTERNAL_ERROR_MSG)
+    }
+}
+
+impl fmt::Display for App<'_> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.name)
+    }
+}
+
+fn two_elements_of<I, T>(mut iter: I) -> Option<(T, T)>
+where
+    I: Iterator<Item = T>,
+{
+    let first = iter.next();
+    let second = iter.next();
+
+    match (first, second) {
+        (Some(first), Some(second)) => Some((first, second)),
+        _ => None,
+    }
+}
+
+#[test]
+fn check_auto_traits() {
+    static_assertions::assert_impl_all!(Command: Send, Sync, Unpin);
+}
diff --git a/vendor/clap-3.2.20/src/builder/debug_asserts.rs b/vendor/clap-3.2.20/src/builder/debug_asserts.rs
new file mode 100644
index 000000000..864b8b479
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/debug_asserts.rs
@@ -0,0 +1,851 @@
+use std::cmp::Ordering;
+
+use clap_lex::RawOsStr;
+
+use crate::builder::arg::ArgProvider;
+use crate::mkeymap::KeyType;
+use crate::ArgAction;
+use crate::{Arg, Command, ValueHint};
+
+pub(crate) fn assert_app(cmd: &Command) {
+    debug!("Command::_debug_asserts");
+
+    let mut short_flags = vec![];
+    let mut long_flags = vec![];
+
+    // Invalid version flag settings
+    if cmd.get_version().is_none() && cmd.get_long_version().is_none() {
+        // PropagateVersion is meaningless if there is no version
+        assert!(
+            !cmd.is_propagate_version_set(),
+            "Command {}: No version information via Command::version or Command::long_version to propagate",
+            cmd.get_name(),
+        );
+
+        // Used `Command::mut_arg("version", ..) but did not provide any version information to display
+        let version_needed = cmd
+            .get_arguments()
+            .filter(|x| {
+                let action_set = matches!(x.get_action(), ArgAction::Version);
+                #[cfg(not(feature = "unstable-v4"))]
+                let provider_set = matches!(x.provider, ArgProvider::GeneratedMutated);
+                #[cfg(feature = "unstable-v4")]
+                let provider_set = matches!(
+                    x.provider,
+                    ArgProvider::User | ArgProvider::GeneratedMutated
+                );
+                action_set && provider_set
+            })
+            .map(|x| x.get_id())
+            .collect::<Vec<_>>();
+
+        assert_eq!(version_needed, Vec::<&str>::new(), "Command {}: `ArgAction::Version` used without providing Command::version or Command::long_version"
+            ,cmd.get_name()
+        );
+    }
+
+    for sc in cmd.get_subcommands() {
+        if let Some(s) = sc.get_short_flag().as_ref() {
+            short_flags.push(Flag::Command(format!("-{}", s), sc.get_name()));
+        }
+
+        for short_alias in sc.get_all_short_flag_aliases() {
+            short_flags.push(Flag::Command(format!("-{}", short_alias), sc.get_name()));
+        }
+
+        if let Some(l) = sc.get_long_flag().as_ref() {
+            #[cfg(feature = "unstable-v4")]
+            {
+                assert!(!l.starts_with('-'), "Command {}: long_flag {:?} must not start with a `-`, that will be handled by the parser", sc.get_name(), l);
+            }
+            long_flags.push(Flag::Command(format!("--{}", l), sc.get_name()));
+        }
+
+        for long_alias in sc.get_all_long_flag_aliases() {
+            long_flags.push(Flag::Command(format!("--{}", long_alias), sc.get_name()));
+        }
+    }
+
+    for arg in cmd.get_arguments() {
+        assert_arg(arg);
+
+        assert!(
+            !cmd.is_multicall_set(),
+            "Command {}: Arguments like {} cannot be set on a multicall command",
+            cmd.get_name(),
+            arg.name
+        );
+
+        if let Some(s) = arg.short.as_ref() {
+            short_flags.push(Flag::Arg(format!("-{}", s), &*arg.name));
+        }
+
+        for (short_alias, _) in &arg.short_aliases {
+            short_flags.push(Flag::Arg(format!("-{}", short_alias), arg.name));
+        }
+
+        if let Some(l) = arg.long.as_ref() {
+            #[cfg(feature = "unstable-v4")]
+            {
+                assert!(!l.starts_with('-'), "Argument {}: long {:?} must not start with a `-`, that will be handled by the parser", arg.name, l);
+            }
+            long_flags.push(Flag::Arg(format!("--{}", l), &*arg.name));
+        }
+
+        for (long_alias, _) in &arg.aliases {
+            long_flags.push(Flag::Arg(format!("--{}", long_alias), arg.name));
+        }
+
+        // Name conflicts
+        assert!(
+            cmd.two_args_of(|x| x.id == arg.id).is_none(),
+            "Command {}: Argument names must be unique, but '{}' is in use by more than one argument or group",
+            cmd.get_name(),
+            arg.name,
+        );
+
+        // Long conflicts
+        if let Some(l) = arg.long {
+            if let Some((first, second)) = cmd.two_args_of(|x| x.long == Some(l)) {
+                panic!(
+                    "Command {}: Long option names must be unique for each argument, \
+                        but '--{}' is in use by both '{}' and '{}'",
+                    cmd.get_name(),
+                    l,
+                    first.name,
+                    second.name
+                )
+            }
+        }
+
+        // Short conflicts
+        if let Some(s) = arg.short {
+            if let Some((first, second)) = cmd.two_args_of(|x| x.short == Some(s)) {
+                panic!(
+                    "Command {}: Short option names must be unique for each argument, \
+                        but '-{}' is in use by both '{}' and '{}'",
+                    cmd.get_name(),
+                    s,
+                    first.name,
+                    second.name
+                )
+            }
+        }
+
+        // Index conflicts
+        if let Some(idx) = arg.index {
+            if let Some((first, second)) =
+                cmd.two_args_of(|x| x.is_positional() && x.index == Some(idx))
+            {
+                panic!(
+                    "Command {}: Argument '{}' has the same index as '{}' \
+                    and they are both positional arguments\n\n\t \
+                    Use Arg::multiple_values(true) to allow one \
+                    positional argument to take multiple values",
+                    cmd.get_name(),
+                    first.name,
+                    second.name
+                )
+            }
+        }
+
+        // requires, r_if, r_unless
+        for req in &arg.requires {
+            assert!(
+                cmd.id_exists(&req.1),
+                "Command {}: Argument or group '{:?}' specified in 'requires*' for '{}' does not exist",
+                cmd.get_name(),
+                req.1,
+                arg.name,
+            );
+        }
+
+        for req in &arg.r_ifs {
+            #[cfg(feature = "unstable-v4")]
+            {
+                assert!(
+                    !arg.is_required_set(),
+                    "Argument {}: `required` conflicts with `required_if_eq*`",
+                    arg.name
+                );
+            }
+            assert!(
+                cmd.id_exists(&req.0),
+                "Command {}: Argument or group '{:?}' specified in 'required_if_eq*' for '{}' does not exist",
+                    cmd.get_name(),
+                req.0,
+                arg.name
+            );
+        }
+
+        for req in &arg.r_ifs_all {
+            #[cfg(feature = "unstable-v4")]
+            {
+                assert!(
+                    !arg.is_required_set(),
+                    "Argument {}: `required` conflicts with `required_if_eq_all`",
+                    arg.name
+                );
+            }
+            assert!(
+                cmd.id_exists(&req.0),
+                "Command {}: Argument or group '{:?}' specified in 'required_if_eq_all' for '{}' does not exist",
+                    cmd.get_name(),
+                req.0,
+                arg.name
+            );
+        }
+
+        for req in &arg.r_unless {
+            #[cfg(feature = "unstable-v4")]
+            {
+                assert!(
+                    !arg.is_required_set(),
+                    "Argument {}: `required` conflicts with `required_unless*`",
+                    arg.name
+                );
+            }
+            assert!(
+                cmd.id_exists(req),
+                "Command {}: Argument or group '{:?}' specified in 'required_unless*' for '{}' does not exist",
+                    cmd.get_name(),
+                req,
+                arg.name,
+            );
+        }
+
+        for req in &arg.r_unless_all {
+            #[cfg(feature = "unstable-v4")]
+            {
+                assert!(
+                    !arg.is_required_set(),
+                    "Argument {}: `required` conflicts with `required_unless*`",
+                    arg.name
+                );
+            }
+            assert!(
+                cmd.id_exists(req),
+                "Command {}: Argument or group '{:?}' specified in 'required_unless*' for '{}' does not exist",
+                    cmd.get_name(),
+                req,
+                arg.name,
+            );
+        }
+
+        // blacklist
+        for req in &arg.blacklist {
+            assert!(
+                cmd.id_exists(req),
+                "Command {}: Argument or group '{:?}' specified in 'conflicts_with*' for '{}' does not exist",
+                    cmd.get_name(),
+                req,
+                arg.name,
+            );
+        }
+
+        if arg.is_last_set() {
+            assert!(
+                arg.long.is_none(),
+                "Command {}: Flags or Options cannot have last(true) set. '{}' has both a long and last(true) set.",
+                    cmd.get_name(),
+                arg.name
+            );
+            assert!(
+                arg.short.is_none(),
+                "Command {}: Flags or Options cannot have last(true) set. '{}' has both a short and last(true) set.",
+                    cmd.get_name(),
+                arg.name
+            );
+        }
+
+        assert!(
+            !(arg.is_required_set() && arg.is_global_set()),
+            "Command {}: Global arguments cannot be required.\n\n\t'{}' is marked as both global and required",
+                    cmd.get_name(),
+            arg.name
+        );
+
+        // validators
+        assert!(
+            arg.validator.is_none() || arg.validator_os.is_none(),
+            "Command {}: Argument '{}' has both `validator` and `validator_os` set which is not allowed",
+                    cmd.get_name(),
+            arg.name
+        );
+
+        if arg.get_value_hint() == ValueHint::CommandWithArguments {
+            assert!(
+                arg.is_positional(),
+                "Command {}: Argument '{}' has hint CommandWithArguments and must be positional.",
+                cmd.get_name(),
+                arg.name
+            );
+
+            assert!(
+                cmd.is_trailing_var_arg_set(),
+                "Command {}: Positional argument '{}' has hint CommandWithArguments, so Command must have TrailingVarArg set.",
+                    cmd.get_name(),
+                arg.name
+            );
+        }
+    }
+
+    for group in cmd.get_groups() {
+        // Name conflicts
+        assert!(
+            cmd.get_groups().filter(|x| x.id == group.id).count() < 2,
+            "Command {}: Argument group name must be unique\n\n\t'{}' is already in use",
+            cmd.get_name(),
+            group.name,
+        );
+
+        // Groups should not have naming conflicts with Args
+        assert!(
+            !cmd.get_arguments().any(|x| x.id == group.id),
+            "Command {}: Argument group name '{}' must not conflict with argument name",
+            cmd.get_name(),
+            group.name,
+        );
+
+        for arg in &group.args {
+            // Args listed inside groups should exist
+            assert!(
+                cmd.get_arguments().any(|x| x.id == *arg),
+                "Command {}: Argument group '{}' contains non-existent argument '{:?}'",
+                cmd.get_name(),
+                group.name,
+                arg
+            );
+        }
+    }
+
+    // Conflicts between flags and subcommands
+
+    long_flags.sort_unstable();
+    short_flags.sort_unstable();
+
+    detect_duplicate_flags(&long_flags, "long");
+    detect_duplicate_flags(&short_flags, "short");
+
+    _verify_positionals(cmd);
+
+    if let Some(help_template) = cmd.get_help_template() {
+        assert!(
+            !help_template.contains("{flags}"),
+            "Command {}: {}",
+                    cmd.get_name(),
+            "`{flags}` template variable was removed in clap3, they are now included in `{options}`",
+        );
+        assert!(
+            !help_template.contains("{unified}"),
+            "Command {}: {}",
+            cmd.get_name(),
+            "`{unified}` template variable was removed in clap3, use `{options}` instead"
+        );
+    }
+
+    cmd._panic_on_missing_help(cmd.is_help_expected_set());
+    assert_app_flags(cmd);
+}
+
+#[derive(Eq)]
+enum Flag<'a> {
+    Command(String, &'a str),
+    Arg(String, &'a str),
+}
+
+impl PartialEq for Flag<'_> {
+    fn eq(&self, other: &Flag) -> bool {
+        self.cmp(other) == Ordering::Equal
+    }
+}
+
+impl PartialOrd for Flag<'_> {
+    fn partial_cmp(&self, other: &Flag) -> Option<Ordering> {
+        use Flag::*;
+
+        match (self, other) {
+            (Command(s1, _), Command(s2, _))
+            | (Arg(s1, _), Arg(s2, _))
+            | (Command(s1, _), Arg(s2, _))
+            | (Arg(s1, _), Command(s2, _)) => {
+                if s1 == s2 {
+                    Some(Ordering::Equal)
+                } else {
+                    s1.partial_cmp(s2)
+                }
+            }
+        }
+    }
+}
+
+impl Ord for Flag<'_> {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.partial_cmp(other).unwrap()
+    }
+}
+
+fn detect_duplicate_flags(flags: &[Flag], short_or_long: &str) {
+    use Flag::*;
+
+    for (one, two) in find_duplicates(flags) {
+        match (one, two) {
+            (Command(flag, one), Command(_, another)) if one != another => panic!(
+                "the '{}' {} flag is specified for both '{}' and '{}' subcommands",
+                flag, short_or_long, one, another
+            ),
+
+            (Arg(flag, one), Arg(_, another)) if one != another => panic!(
+                "{} option names must be unique, but '{}' is in use by both '{}' and '{}'",
+                short_or_long, flag, one, another
+            ),
+
+            (Arg(flag, arg), Command(_, sub)) | (Command(flag, sub), Arg(_, arg)) => panic!(
+                "the '{}' {} flag for the '{}' argument conflicts with the short flag \
+                     for '{}' subcommand",
+                flag, short_or_long, arg, sub
+            ),
+
+            _ => {}
+        }
+    }
+}
+
+/// Find duplicates in a sorted array.
+///
+/// The algorithm is simple: the array is sorted, duplicates
+/// must be placed next to each other, we can check only adjacent elements.
+fn find_duplicates<T: PartialEq>(slice: &[T]) -> impl Iterator<Item = (&T, &T)> {
+    slice.windows(2).filter_map(|w| {
+        if w[0] == w[1] {
+            Some((&w[0], &w[1]))
+        } else {
+            None
+        }
+    })
+}
+
+fn assert_app_flags(cmd: &Command) {
+    macro_rules! checker {
+        ($a:ident requires $($b:ident)|+) => {
+            if cmd.$a() {
+                let mut s = String::new();
+
+                $(
+                    if !cmd.$b() {
+                        s.push_str(&format!("  AppSettings::{} is required when AppSettings::{} is set.\n", std::stringify!($b), std::stringify!($a)));
+                    }
+                )+
+
+                if !s.is_empty() {
+                    panic!("{}", s)
+                }
+            }
+        };
+        ($a:ident conflicts $($b:ident)|+) => {
+            if cmd.$a() {
+                let mut s = String::new();
+
+                $(
+                    if cmd.$b() {
+                        s.push_str(&format!("  AppSettings::{} conflicts with AppSettings::{}.\n", std::stringify!($b), std::stringify!($a)));
+                    }
+                )+
+
+                if !s.is_empty() {
+                    panic!("{}\n{}", cmd.get_name(), s)
+                }
+            }
+        };
+    }
+
+    checker!(is_allow_invalid_utf8_for_external_subcommands_set requires is_allow_external_subcommands_set);
+    checker!(is_multicall_set conflicts is_no_binary_name_set);
+}
+
+#[cfg(debug_assertions)]
+fn _verify_positionals(cmd: &Command) -> bool {
+    debug!("Command::_verify_positionals");
+    // Because you must wait until all arguments have been supplied, this is the first chance
+    // to make assertions on positional argument indexes
+    //
+    // First we verify that the index highest supplied index, is equal to the number of
+    // positional arguments to verify there are no gaps (i.e. supplying an index of 1 and 3
+    // but no 2)
+
+    let highest_idx = cmd
+        .get_keymap()
+        .keys()
+        .filter_map(|x| {
+            if let KeyType::Position(n) = x {
+                Some(*n)
+            } else {
+                None
+            }
+        })
+        .max()
+        .unwrap_or(0);
+
+    let num_p = cmd.get_keymap().keys().filter(|x| x.is_position()).count();
+
+    assert!(
+        highest_idx == num_p,
+        "Found positional argument whose index is {} but there \
+             are only {} positional arguments defined",
+        highest_idx,
+        num_p
+    );
+
+    // Next we verify that only the highest index has takes multiple arguments (if any)
+    let only_highest = |a: &Arg| a.is_multiple() && (a.index.unwrap_or(0) != highest_idx);
+    if cmd.get_positionals().any(only_highest) {
+        // First we make sure if there is a positional that allows multiple values
+        // the one before it (second to last) has one of these:
+        //  * a value terminator
+        //  * ArgSettings::Last
+        //  * The last arg is Required
+
+        // We can't pass the closure (it.next()) to the macro directly because each call to
+        // find() (iterator, not macro) gets called repeatedly.
+        let last = &cmd.get_keymap()[&KeyType::Position(highest_idx)];
+        let second_to_last = &cmd.get_keymap()[&KeyType::Position(highest_idx - 1)];
+
+        // Either the final positional is required
+        // Or the second to last has a terminator or .last(true) set
+        let ok = last.is_required_set()
+            || (second_to_last.terminator.is_some() || second_to_last.is_last_set())
+            || last.is_last_set();
+        assert!(
+            ok,
+            "When using a positional argument with .multiple_values(true) that is *not the \
+                 last* positional argument, the last positional argument (i.e. the one \
+                 with the highest index) *must* have .required(true) or .last(true) set."
+        );
+
+        // We make sure if the second to last is Multiple the last is ArgSettings::Last
+        let ok = second_to_last.is_multiple() || last.is_last_set();
+        assert!(
+            ok,
+            "Only the last positional argument, or second to last positional \
+                 argument may be set to .multiple_values(true)"
+        );
+
+        // Next we check how many have both Multiple and not a specific number of values set
+        let count = cmd
+            .get_positionals()
+            .filter(|p| {
+                #[allow(deprecated)]
+                {
+                    p.is_multiple_occurrences_set()
+                        || (p.is_multiple_values_set() && p.num_vals.is_none())
+                }
+            })
+            .count();
+        let ok = count <= 1
+            || (last.is_last_set()
+                && last.is_multiple()
+                && second_to_last.is_multiple()
+                && count == 2);
+        assert!(
+            ok,
+            "Only one positional argument with .multiple_values(true) set is allowed per \
+                 command, unless the second one also has .last(true) set"
+        );
+    }
+
+    let mut found = false;
+
+    if cmd.is_allow_missing_positional_set() {
+        // Check that if a required positional argument is found, all positions with a lower
+        // index are also required.
+        let mut foundx2 = false;
+
+        for p in cmd.get_positionals() {
+            if foundx2 && !p.is_required_set() {
+                assert!(
+                    p.is_required_set(),
+                    "Found non-required positional argument with a lower \
+                         index than a required positional argument by two or more: {:?} \
+                         index {:?}",
+                    p.name,
+                    p.index
+                );
+            } else if p.is_required_set() && !p.is_last_set() {
+                // Args that .last(true) don't count since they can be required and have
+                // positionals with a lower index that aren't required
+                // Imagine: prog <req1> [opt1] -- <req2>
+                // Both of these are valid invocations:
+                //      $ prog r1 -- r2
+                //      $ prog r1 o1 -- r2
+                if found {
+                    foundx2 = true;
+                    continue;
+                }
+                found = true;
+                continue;
+            } else {
+                found = false;
+            }
+        }
+    } else {
+        // Check that if a required positional argument is found, all positions with a lower
+        // index are also required
+        for p in (1..=num_p).rev().filter_map(|n| cmd.get_keymap().get(&n)) {
+            if found {
+                assert!(
+                    p.is_required_set(),
+                    "Found non-required positional argument with a lower \
+                         index than a required positional argument: {:?} index {:?}",
+                    p.name,
+                    p.index
+                );
+            } else if p.is_required_set() && !p.is_last_set() {
+                // Args that .last(true) don't count since they can be required and have
+                // positionals with a lower index that aren't required
+                // Imagine: prog <req1> [opt1] -- <req2>
+                // Both of these are valid invocations:
+                //      $ prog r1 -- r2
+                //      $ prog r1 o1 -- r2
+                found = true;
+                continue;
+            }
+        }
+    }
+    assert!(
+        cmd.get_positionals().filter(|p| p.is_last_set()).count() < 2,
+        "Only one positional argument may have last(true) set. Found two."
+    );
+    if cmd
+        .get_positionals()
+        .any(|p| p.is_last_set() && p.is_required_set())
+        && cmd.has_subcommands()
+        && !cmd.is_subcommand_negates_reqs_set()
+    {
+        panic!(
+            "Having a required positional argument with .last(true) set *and* child \
+                 subcommands without setting SubcommandsNegateReqs isn't compatible."
+        );
+    }
+
+    true
+}
+
+fn assert_arg(arg: &Arg) {
+    debug!("Arg::_debug_asserts:{}", arg.name);
+
+    // Self conflict
+    // TODO: this check should be recursive
+    assert!(
+        !arg.blacklist.iter().any(|x| *x == arg.id),
+        "Argument '{}' cannot conflict with itself",
+        arg.name,
+    );
+
+    assert_eq!(
+        arg.get_action().takes_values(),
+        arg.is_takes_value_set(),
+        "Argument `{}`'s selected action {:?} contradicts `takes_value`",
+        arg.name,
+        arg.get_action()
+    );
+    if let Some(action_type_id) = arg.get_action().value_type_id() {
+        assert_eq!(
+            action_type_id,
+            arg.get_value_parser().type_id(),
+            "Argument `{}`'s selected action {:?} contradicts `value_parser` ({:?})",
+            arg.name,
+            arg.get_action(),
+            arg.get_value_parser()
+        );
+    }
+
+    if arg.get_value_hint() != ValueHint::Unknown {
+        assert!(
+            arg.is_takes_value_set(),
+            "Argument '{}' has value hint but takes no value",
+            arg.name
+        );
+
+        if arg.get_value_hint() == ValueHint::CommandWithArguments {
+            assert!(
+                arg.is_multiple_values_set(),
+                "Argument '{}' uses hint CommandWithArguments and must accept multiple values",
+                arg.name
+            )
+        }
+    }
+
+    if arg.index.is_some() {
+        assert!(
+            arg.is_positional(),
+            "Argument '{}' is a positional argument and can't have short or long name versions",
+            arg.name
+        );
+        assert!(
+            arg.is_takes_value_set(),
+            "Argument '{}` is positional, it must take a value",
+            arg.name
+        );
+    }
+
+    #[cfg(feature = "unstable-v4")]
+    {
+        let num_vals = arg.get_num_vals().unwrap_or(usize::MAX);
+        let num_val_names = arg.get_value_names().unwrap_or(&[]).len();
+        if num_vals < num_val_names {
+            panic!(
+                "Argument {}: Too many value names ({}) compared to number_of_values ({})",
+                arg.name, num_val_names, num_vals
+            );
+        }
+    }
+
+    assert_arg_flags(arg);
+
+    assert_defaults(arg, "default_value", arg.default_vals.iter().copied());
+    assert_defaults(
+        arg,
+        "default_missing_value",
+        arg.default_missing_vals.iter().copied(),
+    );
+    assert_defaults(
+        arg,
+        "default_value_if",
+        arg.default_vals_ifs
+            .iter()
+            .filter_map(|(_, _, default)| *default),
+    );
+}
+
+fn assert_arg_flags(arg: &Arg) {
+    macro_rules! checker {
+        ($a:ident requires $($b:ident)|+) => {
+            if arg.$a() {
+                let mut s = String::new();
+
+                $(
+                    if !arg.$b() {
+                        s.push_str(&format!("  Arg::{} is required when Arg::{} is set.\n", std::stringify!($b), std::stringify!($a)));
+                    }
+                )+
+
+                if !s.is_empty() {
+                    panic!("Argument {:?}\n{}", arg.get_id(), s)
+                }
+            }
+        }
+    }
+
+    checker!(is_require_value_delimiter_set requires is_takes_value_set);
+    checker!(is_require_value_delimiter_set requires is_use_value_delimiter_set);
+    checker!(is_hide_possible_values_set requires is_takes_value_set);
+    checker!(is_allow_hyphen_values_set requires is_takes_value_set);
+    checker!(is_require_equals_set requires is_takes_value_set);
+    checker!(is_last_set requires is_takes_value_set);
+    checker!(is_hide_default_value_set requires is_takes_value_set);
+    checker!(is_multiple_values_set requires is_takes_value_set);
+    checker!(is_ignore_case_set requires is_takes_value_set);
+    {
+        #![allow(deprecated)]
+        checker!(is_forbid_empty_values_set requires is_takes_value_set);
+        checker!(is_allow_invalid_utf8_set requires is_takes_value_set);
+    }
+}
+
+fn assert_defaults<'d>(
+    arg: &Arg,
+    field: &'static str,
+    defaults: impl IntoIterator<Item = &'d std::ffi::OsStr>,
+) {
+    for default_os in defaults {
+        if let Some(default_s) = default_os.to_str() {
+            if !arg.possible_vals.is_empty() {
+                if let Some(delim) = arg.get_value_delimiter() {
+                    for part in default_s.split(delim) {
+                        assert!(
+                            arg.possible_vals.iter().any(|possible_val| {
+                                possible_val.matches(part, arg.is_ignore_case_set())
+                            }),
+                            "Argument `{}`'s {}={} doesn't match possible values",
+                            arg.name,
+                            field,
+                            part
+                        )
+                    }
+                } else {
+                    assert!(
+                        arg.possible_vals.iter().any(|possible_val| {
+                            possible_val.matches(default_s, arg.is_ignore_case_set())
+                        }),
+                        "Argument `{}`'s {}={} doesn't match possible values",
+                        arg.name,
+                        field,
+                        default_s
+                    );
+                }
+            }
+
+            if let Some(validator) = arg.validator.as_ref() {
+                let mut validator = validator.lock().unwrap();
+                if let Some(delim) = arg.get_value_delimiter() {
+                    for part in default_s.split(delim) {
+                        if let Err(err) = validator(part) {
+                            panic!(
+                                "Argument `{}`'s {}={} failed validation: {}",
+                                arg.name, field, part, err
+                            );
+                        }
+                    }
+                } else if let Err(err) = validator(default_s) {
+                    panic!(
+                        "Argument `{}`'s {}={} failed validation: {}",
+                        arg.name, field, default_s, err
+                    );
+                }
+            }
+        }
+
+        if let Some(validator) = arg.validator_os.as_ref() {
+            let mut validator = validator.lock().unwrap();
+            if let Some(delim) = arg.get_value_delimiter() {
+                let default_os = RawOsStr::new(default_os);
+                for part in default_os.split(delim) {
+                    if let Err(err) = validator(&part.to_os_str()) {
+                        panic!(
+                            "Argument `{}`'s {}={:?} failed validation: {}",
+                            arg.name, field, part, err
+                        );
+                    }
+                }
+            } else if let Err(err) = validator(default_os) {
+                panic!(
+                    "Argument `{}`'s {}={:?} failed validation: {}",
+                    arg.name, field, default_os, err
+                );
+            }
+        }
+
+        let value_parser = arg.get_value_parser();
+        let assert_cmd = Command::new("assert");
+        if let Some(delim) = arg.get_value_delimiter() {
+            let default_os = RawOsStr::new(default_os);
+            for part in default_os.split(delim) {
+                if let Err(err) = value_parser.parse_ref(&assert_cmd, Some(arg), &part.to_os_str())
+                {
+                    panic!(
+                        "Argument `{}`'s {}={:?} failed validation: {}",
+                        arg.name,
+                        field,
+                        part.to_str_lossy(),
+                        err
+                    );
+                }
+            }
+        } else if let Err(err) = value_parser.parse_ref(&assert_cmd, Some(arg), default_os) {
+            panic!(
+                "Argument `{}`'s {}={:?} failed validation: {}",
+                arg.name, field, default_os, err
+            );
+        }
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/macros.rs b/vendor/clap-3.2.20/src/builder/macros.rs
new file mode 100644
index 000000000..5be4d205e
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/macros.rs
@@ -0,0 +1,180 @@
+#[cfg(feature = "yaml")]
+macro_rules! yaml_tuple2 {
+    ($a:ident, $v:ident, $c:ident) => {{
+        if let Some(vec) = $v.as_vec() {
+            for ys in vec {
+                if let Some(tup) = ys.as_vec() {
+                    debug_assert_eq!(2, tup.len());
+                    $a = $a.$c(yaml_str!(tup[0]), yaml_str!(tup[1]));
+                } else {
+                    panic!("Failed to convert YAML value to vec");
+                }
+            }
+        } else {
+            panic!("Failed to convert YAML value to vec");
+        }
+        $a
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_tuple3 {
+    ($a:ident, $v:ident, $c:ident) => {{
+        if let Some(vec) = $v.as_vec() {
+            for ys in vec {
+                if let Some(tup) = ys.as_vec() {
+                    debug_assert_eq!(3, tup.len());
+                    $a = $a.$c(
+                        yaml_str!(tup[0]),
+                        yaml_opt_str!(tup[1]),
+                        yaml_opt_str!(tup[2]),
+                    );
+                } else {
+                    panic!("Failed to convert YAML value to vec");
+                }
+            }
+        } else {
+            panic!("Failed to convert YAML value to vec");
+        }
+        $a
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_vec_or_str {
+    ($a:ident, $v:ident, $c:ident) => {{
+        let maybe_vec = $v.as_vec();
+        if let Some(vec) = maybe_vec {
+            for ys in vec {
+                if let Some(s) = ys.as_str() {
+                    $a = $a.$c(s);
+                } else {
+                    panic!("Failed to convert YAML value {:?} to a string", ys);
+                }
+            }
+        } else {
+            if let Some(s) = $v.as_str() {
+                $a = $a.$c(s);
+            } else {
+                panic!(
+                    "Failed to convert YAML value {:?} to either a vec or string",
+                    $v
+                );
+            }
+        }
+        $a
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_vec {
+    ($a:ident, $v:ident, $c:ident) => {{
+        let maybe_vec = $v.as_vec();
+        if let Some(vec) = maybe_vec {
+            let content = vec.into_iter().map(|ys| {
+                if let Some(s) = ys.as_str() {
+                    s
+                } else {
+                    panic!("Failed to convert YAML value {:?} to a string", ys);
+                }
+            });
+            $a = $a.$c(content)
+        } else {
+            panic!("Failed to convert YAML value {:?} to a vec", $v);
+        }
+        $a
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_opt_str {
+    ($v:expr) => {{
+        if !$v.is_null() {
+            Some(
+                $v.as_str()
+                    .unwrap_or_else(|| panic!("failed to convert YAML {:?} value to a string", $v)),
+            )
+        } else {
+            None
+        }
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_char {
+    ($v:expr) => {{
+        $v.as_str()
+            .unwrap_or_else(|| panic!("failed to convert YAML {:?} value to a string", $v))
+            .chars()
+            .next()
+            .unwrap_or_else(|| panic!("Expected char"))
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_str {
+    ($v:expr) => {{
+        $v.as_str()
+            .unwrap_or_else(|| panic!("failed to convert YAML {:?} value to a string", $v))
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_to_char {
+    ($a:ident, $v:ident, $c:ident) => {{
+        $a.$c(yaml_char!($v))
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_to_str {
+    ($a:ident, $v:ident, $c:ident) => {{
+        $a.$c(yaml_str!($v))
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_to_bool {
+    ($a:ident, $v:ident, $c:ident) => {{
+        $a.$c($v
+            .as_bool()
+            .unwrap_or_else(|| panic!("failed to convert YAML {:?} value to a string", $v)))
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_to_usize {
+    ($a:ident, $v:ident, $c:ident) => {{
+        $a.$c($v
+            .as_i64()
+            .unwrap_or_else(|| panic!("failed to convert YAML {:?} value to a string", $v))
+            as usize)
+    }};
+}
+
+#[cfg(feature = "yaml")]
+macro_rules! yaml_to_setting {
+    ($a:ident, $v:ident, $c:ident, $s:ident, $t:literal, $n:expr) => {{
+        if let Some(v) = $v.as_vec() {
+            for ys in v {
+                if let Some(s) = ys.as_str() {
+                    $a = $a.$c(s.parse::<$s>().unwrap_or_else(|_| {
+                        panic!("Unknown {} '{}' found in YAML file for {}", $t, s, $n)
+                    }));
+                } else {
+                    panic!(
+                        "Failed to convert YAML {:?} value to an array of strings",
+                        $v
+                    );
+                }
+            }
+        } else if let Some(v) = $v.as_str() {
+            $a = $a.$c(v
+                .parse::<$s>()
+                .unwrap_or_else(|_| panic!("Unknown {} '{}' found in YAML file for {}", $t, v, $n)))
+        } else {
+            panic!("Failed to convert YAML {:?} value to a string", $v);
+        }
+        $a
+    }};
+}
diff --git a/vendor/clap-3.2.20/src/builder/mod.rs b/vendor/clap-3.2.20/src/builder/mod.rs
new file mode 100644
index 000000000..4f24c74d3
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/mod.rs
@@ -0,0 +1,61 @@
+//! Define [`Command`] line [arguments][`Arg`]
+
+#[macro_use]
+mod macros;
+
+mod action;
+mod app_settings;
+mod arg;
+mod arg_group;
+mod arg_predicate;
+mod arg_settings;
+mod command;
+mod possible_value;
+mod usage_parser;
+mod value_hint;
+mod value_parser;
+
+#[cfg(feature = "regex")]
+mod regex;
+
+#[cfg(debug_assertions)]
+mod debug_asserts;
+
+#[cfg(test)]
+mod tests;
+
+pub use action::ArgAction;
+pub use app_settings::{AppFlags, AppSettings};
+pub use arg::Arg;
+pub use arg_group::ArgGroup;
+pub use arg_settings::{ArgFlags, ArgSettings};
+pub use command::Command;
+pub use possible_value::PossibleValue;
+pub use value_hint::ValueHint;
+pub use value_parser::PossibleValuesParser;
+pub use value_parser::RangedI64ValueParser;
+pub use value_parser::RangedU64ValueParser;
+pub use value_parser::StringValueParser;
+pub use value_parser::TypedValueParser;
+pub use value_parser::ValueParser;
+pub use value_parser::ValueParserFactory;
+pub use value_parser::_AnonymousValueParser;
+pub use value_parser::_AutoValueParser;
+pub use value_parser::via_prelude;
+pub use value_parser::BoolValueParser;
+pub use value_parser::BoolishValueParser;
+pub use value_parser::EnumValueParser;
+pub use value_parser::FalseyValueParser;
+pub use value_parser::NonEmptyStringValueParser;
+pub use value_parser::OsStringValueParser;
+pub use value_parser::PathBufValueParser;
+
+#[allow(deprecated)]
+pub use command::App;
+
+#[cfg(feature = "regex")]
+pub use self::regex::RegexRef;
+
+pub(crate) use action::CountType;
+pub(crate) use arg::display_arg_val;
+pub(crate) use arg_predicate::ArgPredicate;
diff --git a/vendor/clap-3.2.20/src/builder/possible_value.rs b/vendor/clap-3.2.20/src/builder/possible_value.rs
new file mode 100644
index 000000000..1c14217a6
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/possible_value.rs
@@ -0,0 +1,259 @@
+use std::{borrow::Cow, iter};
+
+use crate::util::eq_ignore_case;
+
+/// A possible value of an argument.
+///
+/// This is used for specifying [possible values] of [Args].
+///
+/// **NOTE:** This struct is likely not needed for most usecases as it is only required to
+/// [hide] single values from help messages and shell completions or to attach [help] to possible values.
+///
+/// # Examples
+///
+/// ```rust
+/// # use clap::{Arg, PossibleValue};
+/// let cfg = Arg::new("config")
+///     .takes_value(true)
+///     .value_name("FILE")
+///     .value_parser([
+///         PossibleValue::new("fast"),
+///         PossibleValue::new("slow").help("slower than fast"),
+///         PossibleValue::new("secret speed").hide(true)
+///     ]);
+/// ```
+/// [Args]: crate::Arg
+/// [possible values]: crate::builder::ValueParser::possible_values
+/// [hide]: PossibleValue::hide()
+/// [help]: PossibleValue::help()
+#[derive(Debug, Default, Clone, PartialEq, Eq)]
+pub struct PossibleValue<'help> {
+    name: &'help str,
+    help: Option<&'help str>,
+    aliases: Vec<&'help str>, // (name, visible)
+    hide: bool,
+}
+
+impl<'help> PossibleValue<'help> {
+    /// Create a [`PossibleValue`] with its name.
+    ///
+    /// The name will be used to decide whether this value was provided by the user to an argument.
+    ///
+    /// **NOTE:** In case it is not [hidden] it will also be shown in help messages for arguments
+    /// that use it as a [possible value] and have not hidden them through [`Arg::hide_possible_values(true)`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::PossibleValue;
+    /// PossibleValue::new("fast")
+    /// # ;
+    /// ```
+    /// [hidden]: PossibleValue::hide
+    /// [possible value]: crate::Arg::possible_values
+    /// [`Arg::hide_possible_values(true)`]: crate::Arg::hide_possible_values()
+    pub fn new(name: &'help str) -> Self {
+        PossibleValue {
+            name,
+            ..Default::default()
+        }
+    }
+
+    /// Sets the help description of the value.
+    ///
+    /// This is typically displayed in completions (where supported) and should be a short, one-line
+    /// description.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::PossibleValue;
+    /// PossibleValue::new("slow")
+    ///     .help("not fast")
+    /// # ;
+    /// ```
+    #[inline]
+    #[must_use]
+    pub fn help(mut self, help: &'help str) -> Self {
+        self.help = Some(help);
+        self
+    }
+
+    /// Hides this value from help and shell completions.
+    ///
+    /// This is an alternative to hiding through [`Arg::hide_possible_values(true)`], if you only
+    /// want to hide some values.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::PossibleValue;
+    /// PossibleValue::new("secret")
+    ///     .hide(true)
+    /// # ;
+    /// ```
+    /// [`Arg::hide_possible_values(true)`]: crate::Arg::hide_possible_values()
+    #[inline]
+    #[must_use]
+    pub fn hide(mut self, yes: bool) -> Self {
+        self.hide = yes;
+        self
+    }
+
+    /// Sets a *hidden* alias for this argument value.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::PossibleValue;
+    /// PossibleValue::new("slow")
+    ///     .alias("not-fast")
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn alias(mut self, name: &'help str) -> Self {
+        self.aliases.push(name);
+        self
+    }
+
+    /// Sets multiple *hidden* aliases for this argument value.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::PossibleValue;
+    /// PossibleValue::new("slow")
+    ///     .aliases(["not-fast", "snake-like"])
+    /// # ;
+    /// ```
+    #[must_use]
+    pub fn aliases<I>(mut self, names: I) -> Self
+    where
+        I: IntoIterator<Item = &'help str>,
+    {
+        self.aliases.extend(names.into_iter());
+        self
+    }
+}
+
+/// Reflection
+impl<'help> PossibleValue<'help> {
+    /// Get the name of the argument value
+    #[inline]
+    pub fn get_name(&self) -> &'help str {
+        self.name
+    }
+
+    /// Get the help specified for this argument, if any
+    #[inline]
+    pub fn get_help(&self) -> Option<&'help str> {
+        self.help
+    }
+
+    /// Get the help specified for this argument, if any and the argument
+    /// value is not hidden
+    #[inline]
+    #[cfg(feature = "unstable-v4")]
+    pub(crate) fn get_visible_help(&self) -> Option<&'help str> {
+        if !self.hide {
+            self.help
+        } else {
+            None
+        }
+    }
+
+    /// Deprecated, replaced with [`PossibleValue::is_hide_set`]
+    #[inline]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `PossibleValue::is_hide_set`")
+    )]
+    pub fn is_hidden(&self) -> bool {
+        self.is_hide_set()
+    }
+
+    /// Report if [`PossibleValue::hide`] is set
+    #[inline]
+    pub fn is_hide_set(&self) -> bool {
+        self.hide
+    }
+
+    /// Report if PossibleValue is not hidden and has a help message
+    pub(crate) fn should_show_help(&self) -> bool {
+        !self.hide && self.help.is_some()
+    }
+
+    /// Get the name if argument value is not hidden, `None` otherwise
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.4",
+            note = "Use `PossibleValue::is_hide_set` and `PossibleValue::get_name`"
+        )
+    )]
+    pub fn get_visible_name(&self) -> Option<&'help str> {
+        if self.hide {
+            None
+        } else {
+            Some(self.name)
+        }
+    }
+
+    /// Get the name if argument value is not hidden, `None` otherwise,
+    /// but wrapped in quotes if it contains whitespace
+    pub(crate) fn get_visible_quoted_name(&self) -> Option<Cow<'help, str>> {
+        if !self.hide {
+            Some(if self.name.contains(char::is_whitespace) {
+                format!("{:?}", self.name).into()
+            } else {
+                self.name.into()
+            })
+        } else {
+            None
+        }
+    }
+
+    /// Returns all valid values of the argument value.
+    ///
+    /// Namely the name and all aliases.
+    pub fn get_name_and_aliases(&self) -> impl Iterator<Item = &'help str> + '_ {
+        iter::once(&self.name).chain(&self.aliases).copied()
+    }
+
+    /// Tests if the value is valid for this argument value
+    ///
+    /// The value is valid if it is either the name or one of the aliases.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::PossibleValue;
+    /// let arg_value = PossibleValue::new("fast").alias("not-slow");
+    ///
+    /// assert!(arg_value.matches("fast", false));
+    /// assert!(arg_value.matches("not-slow", false));
+    ///
+    /// assert!(arg_value.matches("FAST", true));
+    /// assert!(!arg_value.matches("FAST", false));
+    /// ```
+    pub fn matches(&self, value: &str, ignore_case: bool) -> bool {
+        if ignore_case {
+            self.get_name_and_aliases()
+                .any(|name| eq_ignore_case(name, value))
+        } else {
+            self.get_name_and_aliases().any(|name| name == value)
+        }
+    }
+}
+
+impl<'help> From<&'help str> for PossibleValue<'help> {
+    fn from(s: &'help str) -> Self {
+        Self::new(s)
+    }
+}
+
+impl<'help> From<&'help &'help str> for PossibleValue<'help> {
+    fn from(s: &'help &'help str) -> Self {
+        Self::new(s)
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/regex.rs b/vendor/clap-3.2.20/src/builder/regex.rs
new file mode 100644
index 000000000..bf3a78e0c
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/regex.rs
@@ -0,0 +1,88 @@
+use ::regex::{Error, Regex, RegexSet};
+
+use core::{convert::TryFrom, ops::Deref, str::FromStr};
+use std::borrow::Cow;
+
+/// Contains either a regular expression or a set of them or a reference to one.
+///
+/// See [Arg::validator_regex(][crate::Arg::validator_regex] to set this on an argument.
+#[derive(Debug, Clone)]
+pub enum RegexRef<'a> {
+    /// Used if the underlying is a regex set
+    RegexSet(Cow<'a, RegexSet>),
+    /// Used if the underlying is a regex
+    Regex(Cow<'a, Regex>),
+}
+
+impl<'a> RegexRef<'a> {
+    pub(crate) fn is_match(&self, text: &str) -> bool {
+        match self {
+            Self::Regex(r) => r.deref().is_match(text),
+            Self::RegexSet(r) => r.deref().is_match(text),
+        }
+    }
+}
+
+impl<'a> From<&'a Regex> for RegexRef<'a> {
+    fn from(r: &'a Regex) -> Self {
+        Self::Regex(Cow::Borrowed(r))
+    }
+}
+
+impl<'a> From<Regex> for RegexRef<'a> {
+    fn from(r: Regex) -> Self {
+        Self::Regex(Cow::Owned(r))
+    }
+}
+
+impl<'a> From<&'a RegexSet> for RegexRef<'a> {
+    fn from(r: &'a RegexSet) -> Self {
+        Self::RegexSet(Cow::Borrowed(r))
+    }
+}
+
+impl<'a> From<RegexSet> for RegexRef<'a> {
+    fn from(r: RegexSet) -> Self {
+        Self::RegexSet(Cow::Owned(r))
+    }
+}
+
+impl<'a> TryFrom<&'a str> for RegexRef<'a> {
+    type Error = <Self as FromStr>::Err;
+
+    fn try_from(r: &'a str) -> Result<Self, Self::Error> {
+        Self::from_str(r)
+    }
+}
+
+impl<'a> FromStr for RegexRef<'a> {
+    type Err = Error;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        Regex::from_str(s).map(|v| Self::Regex(Cow::Owned(v)))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use core::convert::TryInto;
+
+    #[test]
+    fn test_try_from_with_valid_string() {
+        let t: Result<RegexRef, _> = "^Hello, World$".try_into();
+        assert!(t.is_ok())
+    }
+
+    #[test]
+    fn test_try_from_with_invalid_string() {
+        let t: Result<RegexRef, _> = "^Hello, World)$".try_into();
+        assert!(t.is_err());
+    }
+
+    #[test]
+    fn from_str() {
+        let t: Result<RegexRef, _> = RegexRef::from_str("^Hello, World");
+        assert!(t.is_ok());
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/tests.rs b/vendor/clap-3.2.20/src/builder/tests.rs
new file mode 100644
index 000000000..76c8b8785
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/tests.rs
@@ -0,0 +1,56 @@
+use crate::Arg;
+use crate::Command;
+
+#[test]
+fn propagate_version() {
+    let mut cmd = Command::new("test")
+        .propagate_version(true)
+        .version("1.1")
+        .subcommand(Command::new("sub1"));
+    cmd._propagate();
+    assert_eq!(
+        cmd.get_subcommands().next().unwrap().get_version(),
+        Some("1.1")
+    );
+}
+
+#[test]
+fn global_setting() {
+    let mut cmd = Command::new("test")
+        .disable_version_flag(true)
+        .subcommand(Command::new("subcmd"));
+    cmd._propagate();
+    assert!(cmd
+        .get_subcommands()
+        .find(|s| s.get_name() == "subcmd")
+        .unwrap()
+        .is_disable_version_flag_set());
+}
+
+// This test will *fail to compile* if Command is not Send + Sync
+#[test]
+fn app_send_sync() {
+    fn foo<T: Send + Sync>(_: T) {}
+    foo(Command::new("test"))
+}
+
+#[test]
+fn issue_2090() {
+    let mut cmd = Command::new("cmd")
+        .disable_version_flag(true)
+        .subcommand(Command::new("sub"));
+    cmd._build_self();
+
+    assert!(cmd
+        .get_subcommands()
+        .next()
+        .unwrap()
+        .is_disable_version_flag_set());
+}
+
+// This test will *fail to compile* if Arg is not Send + Sync
+#[test]
+fn arg_send_sync() {
+    fn foo<T: Send + Sync>(_: T) {}
+    foo(Arg::new("test"))
+}
diff --git a/vendor/clap-3.2.20/src/builder/usage_parser.rs b/vendor/clap-3.2.20/src/builder/usage_parser.rs
new file mode 100644
index 000000000..85d0d304e
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/usage_parser.rs
@@ -0,0 +1,1277 @@
+#![allow(deprecated)]
+
+// Internal
+use crate::builder::Arg;
+use crate::builder::ArgSettings;
+use crate::INTERNAL_ERROR_MSG;
+
+#[derive(PartialEq, Debug)]
+enum UsageToken {
+    Name,
+    ValName,
+    Short,
+    Long,
+    Help,
+    Multiple,
+    Unknown,
+    Default,
+}
+
+#[derive(Debug)]
+pub(crate) struct UsageParser<'help> {
+    usage: &'help str,
+    pos: usize,
+    start: usize,
+    prev: UsageToken,
+    explicit_name_set: bool,
+}
+
+impl<'help> UsageParser<'help> {
+    fn new(usage: &'help str) -> Self {
+        debug!("new: usage={:?}", usage);
+        UsageParser {
+            usage,
+            pos: 0,
+            start: 0,
+            prev: UsageToken::Unknown,
+            explicit_name_set: false,
+        }
+    }
+
+    pub(crate) fn from_usage(usage: &'help str) -> Self {
+        debug!("UsageParser::from_usage");
+        UsageParser::new(usage)
+    }
+
+    pub(crate) fn parse(mut self) -> Arg<'help> {
+        debug!("UsageParser::parse");
+        let mut arg = Arg::default();
+        loop {
+            debug!("UsageParser::parse:iter: pos={}", self.pos);
+            self.stop_at(token);
+            if let Some(&c) = self.usage.as_bytes().get(self.pos) {
+                match c {
+                    b'-' => self.short_or_long(&mut arg),
+                    b'.' => self.multiple(&mut arg),
+                    b'@' => self.default(&mut arg),
+                    b'\'' => self.help(&mut arg),
+                    _ => self.name(&mut arg),
+                }
+            } else {
+                break;
+            }
+        }
+
+        debug!("UsageParser::parse: vals...{:?}", arg.val_names);
+        arg
+    }
+
+    fn name(&mut self, arg: &mut Arg<'help>) {
+        debug!("UsageParser::name");
+        if *self
+            .usage
+            .as_bytes()
+            .get(self.pos)
+            .expect(INTERNAL_ERROR_MSG)
+            == b'<'
+            && !self.explicit_name_set
+        {
+            arg.settings.set(ArgSettings::Required);
+        }
+        self.pos += 1;
+        self.stop_at(name_end);
+        let name = &self.usage[self.start..self.pos];
+        if self.prev == UsageToken::Unknown {
+            debug!("UsageParser::name: setting name...{}", name);
+            arg.id = name.into();
+            arg.name = name;
+            if arg.long.is_none() && arg.short.is_none() {
+                debug!("name: explicit name set...");
+                self.explicit_name_set = true;
+                self.prev = UsageToken::Name;
+            }
+        } else {
+            debug!("UsageParser::name: setting val name...{}", name);
+            if arg.val_names.is_empty() {
+                arg.settings.set(ArgSettings::TakesValue);
+            }
+            let len = arg.val_names.len();
+            arg.val_names.insert(len, name);
+            self.prev = UsageToken::ValName;
+        }
+    }
+
+    fn stop_at<F>(&mut self, f: F)
+    where
+        F: Fn(u8) -> bool,
+    {
+        debug!("UsageParser::stop_at");
+        self.start = self.pos;
+        self.pos += self.usage[self.start..]
+            .bytes()
+            .take_while(|&b| f(b))
+            .count();
+    }
+
+    fn short_or_long(&mut self, arg: &mut Arg<'help>) {
+        debug!("UsageParser::short_or_long");
+        self.pos += 1;
+        if *self
+            .usage
+            .as_bytes()
+            .get(self.pos)
+            .expect(INTERNAL_ERROR_MSG)
+            == b'-'
+        {
+            self.pos += 1;
+            self.long(arg);
+            return;
+        }
+        self.short(arg)
+    }
+
+    fn long(&mut self, arg: &mut Arg<'help>) {
+        debug!("UsageParser::long");
+        self.stop_at(long_end);
+        let name = &self.usage[self.start..self.pos];
+        if !self.explicit_name_set {
+            debug!("UsageParser::long: setting name...{}", name);
+            arg.id = name.into();
+            arg.name = name;
+        }
+        debug!("UsageParser::long: setting long...{}", name);
+        arg.long = Some(name);
+        self.prev = UsageToken::Long;
+    }
+
+    fn short(&mut self, arg: &mut Arg<'help>) {
+        debug!("UsageParser::short");
+        let start = &self.usage[self.pos..];
+        let short = start.chars().next().expect(INTERNAL_ERROR_MSG);
+        debug!("UsageParser::short: setting short...{}", short);
+        arg.short = Some(short);
+        if arg.name.is_empty() {
+            // --long takes precedence but doesn't set self.explicit_name_set
+            let name = &start[..short.len_utf8()];
+            debug!("UsageParser::short: setting name...{}", name);
+            arg.id = name.into();
+            arg.name = name;
+        }
+        self.prev = UsageToken::Short;
+    }
+
+    // "something..."
+    fn multiple(&mut self, arg: &mut Arg) {
+        debug!("UsageParser::multiple");
+        let mut dot_counter = 1;
+        let start = self.pos;
+        let mut bytes = self.usage[start..].bytes();
+        while bytes.next() == Some(b'.') {
+            dot_counter += 1;
+            self.pos += 1;
+            if dot_counter == 3 {
+                debug!("UsageParser::multiple: setting multiple");
+                arg.settings.set(ArgSettings::MultipleOccurrences);
+                if arg.is_takes_value_set() {
+                    arg.settings.set(ArgSettings::MultipleValues);
+                    arg.settings.set(ArgSettings::UseValueDelimiter);
+                    arg.val_delim.get_or_insert(',');
+                }
+                self.prev = UsageToken::Multiple;
+                self.pos += 1;
+                break;
+            }
+        }
+    }
+
+    fn help(&mut self, arg: &mut Arg<'help>) {
+        debug!("UsageParser::help");
+        self.stop_at(help_start);
+        self.start = self.pos + 1;
+        self.pos = self.usage.len() - 1;
+        debug!(
+            "UsageParser::help: setting help...{}",
+            &self.usage[self.start..self.pos]
+        );
+        arg.help = Some(&self.usage[self.start..self.pos]);
+        self.pos += 1; // Move to next byte to keep from thinking ending ' is a start
+        self.prev = UsageToken::Help;
+    }
+
+    fn default(&mut self, arg: &mut Arg<'help>) {
+        debug!(
+            "UsageParser::default: from=\"{}\"",
+            &self.usage[self.pos..self.usage.len()]
+        );
+        self.pos += 1; // Skip @
+        self.stop_at(default_value_end); // Find first space after value
+        debug!(
+            "UsageParser::default: setting default...\"{}\"",
+            &self.usage[self.start..self.pos]
+        );
+        arg.settings.set(ArgSettings::TakesValue);
+        arg.default_vals = vec![std::ffi::OsStr::new(&self.usage[self.start..self.pos])];
+        self.prev = UsageToken::Default;
+    }
+}
+
+#[inline]
+fn name_end(b: u8) -> bool {
+    b != b']' && b != b'>'
+}
+
+#[inline]
+fn token(b: u8) -> bool {
+    b != b'\'' && b != b'.' && b != b'<' && b != b'[' && b != b'-' && b != b'@'
+}
+
+#[inline]
+fn long_end(b: u8) -> bool {
+    b != b'\'' && b != b'.' && b != b'<' && b != b'[' && b != b'=' && b != b' '
+}
+
+#[inline]
+fn help_start(b: u8) -> bool {
+    b != b'\''
+}
+
+#[inline]
+fn default_value_end(b: u8) -> bool {
+    b != b' '
+}
+
+#[cfg(test)]
+mod test {
+    #![allow(deprecated)]
+
+    use crate::builder::{Arg, ArgSettings};
+
+    #[allow(clippy::cognitive_complexity)]
+    #[test]
+    fn create_flag_usage() {
+        let a = Arg::from_usage("[flag] -f 'some help info'");
+        assert_eq!(a.name, "flag");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("[flag] --flag 'some help info'");
+        assert_eq!(a.name, "flag");
+        assert_eq!(a.long.unwrap(), "flag");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("--flag 'some help info'");
+        assert_eq!(a.name, "flag");
+        assert_eq!(a.long.unwrap(), "flag");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("[flag] -f --flag 'some help info'");
+        assert_eq!(a.name, "flag");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert_eq!(a.long.unwrap(), "flag");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("[flag] -f... 'some help info'");
+        assert_eq!(a.name, "flag");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("[flag] -f --flag... 'some help info'");
+        assert_eq!(a.name, "flag");
+        assert_eq!(a.long.unwrap(), "flag");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("-f --flag... 'some help info'");
+        assert_eq!(a.name, "flag");
+        assert_eq!(a.long.unwrap(), "flag");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("--flags");
+        assert_eq!(a.name, "flags");
+        assert_eq!(a.long.unwrap(), "flags");
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("--flags...");
+        assert_eq!(a.name, "flags");
+        assert_eq!(a.long.unwrap(), "flags");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("[flags] -f");
+        assert_eq!(a.name, "flags");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("[flags] -f...");
+        assert_eq!(a.name, "flags");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("-f 'some help info'");
+        assert_eq!(a.name, "f");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("-f");
+        assert_eq!(a.name, "f");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert!(a.val_names.is_empty());
+
+        let a = Arg::from_usage("-f...");
+        assert_eq!(a.name, "f");
+        assert_eq!(a.short.unwrap(), 'f');
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn create_option_usage0() {
+        // Short only
+        let a = Arg::from_usage("[option] -o [opt] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage1() {
+        let a = Arg::from_usage("-o [opt] 'some help info'");
+        assert_eq!(a.name, "o");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage2() {
+        let a = Arg::from_usage("<option> -o <opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage3() {
+        let a = Arg::from_usage("-o <opt> 'some help info'");
+        assert_eq!(a.name, "o");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage4() {
+        let a = Arg::from_usage("[option] -o [opt]... 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage5() {
+        let a = Arg::from_usage("[option]... -o [opt] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage6() {
+        let a = Arg::from_usage("-o [opt]... 'some help info'");
+        assert_eq!(a.name, "o");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage7() {
+        let a = Arg::from_usage("<option> -o <opt>... 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage8() {
+        let a = Arg::from_usage("<option>... -o <opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage9() {
+        let a = Arg::from_usage("-o <opt>... 'some help info'");
+        assert_eq!(a.name, "o");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert!(a.long.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long1() {
+        let a = Arg::from_usage("[option] --opt [opt] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long2() {
+        let a = Arg::from_usage("--opt [option] 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_long3() {
+        let a = Arg::from_usage("<option> --opt <opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long4() {
+        let a = Arg::from_usage("--opt <option> 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_long5() {
+        let a = Arg::from_usage("[option] --opt [opt]... 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long6() {
+        let a = Arg::from_usage("[option]... --opt [opt] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long7() {
+        let a = Arg::from_usage("--opt [option]... 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_long8() {
+        let a = Arg::from_usage("<option> --opt <opt>... 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long9() {
+        let a = Arg::from_usage("<option>... --opt <opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long10() {
+        let a = Arg::from_usage("--opt <option>... 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals1() {
+        let a = Arg::from_usage("[option] --opt=[opt] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals2() {
+        let a = Arg::from_usage("--opt=[option] 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals3() {
+        let a = Arg::from_usage("<option> --opt=<opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals4() {
+        let a = Arg::from_usage("--opt=<option> 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals5() {
+        let a = Arg::from_usage("[option] --opt=[opt]... 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals6() {
+        let a = Arg::from_usage("[option]... --opt=[opt] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals7() {
+        let a = Arg::from_usage("--opt=[option]... 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals8() {
+        let a = Arg::from_usage("<option> --opt=<opt>... 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals9() {
+        let a = Arg::from_usage("<option>... --opt=<opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_long_equals10() {
+        let a = Arg::from_usage("--opt=<option>... 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both1() {
+        let a = Arg::from_usage("[option] -o --opt [option] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both2() {
+        let a = Arg::from_usage("-o --opt [option] 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both3() {
+        let a = Arg::from_usage("<option> -o --opt <opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_both4() {
+        let a = Arg::from_usage("-o --opt <option> 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both5() {
+        let a = Arg::from_usage("[option]... -o --opt [option] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both6() {
+        let a = Arg::from_usage("-o --opt [option]... 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both7() {
+        let a = Arg::from_usage("<option>... -o --opt <opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_both8() {
+        let a = Arg::from_usage("-o --opt <option>... 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both_equals1() {
+        let a = Arg::from_usage("[option] -o --opt=[option] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both_equals2() {
+        let a = Arg::from_usage("-o --opt=[option] 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both_equals3() {
+        let a = Arg::from_usage("<option> -o --opt=<opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_both_equals4() {
+        let a = Arg::from_usage("-o --opt=<option> 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both_equals5() {
+        let a = Arg::from_usage("[option]... -o --opt=[option] 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both_equals6() {
+        let a = Arg::from_usage("-o --opt=[option]... 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_usage_both_equals7() {
+        let a = Arg::from_usage("<option>... -o --opt=<opt> 'some help info'");
+        assert_eq!(a.name, "option");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"opt"]);
+    }
+
+    #[test]
+    fn create_option_usage_both_equals8() {
+        let a = Arg::from_usage("-o --opt=<option>... 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"option"]);
+    }
+
+    #[test]
+    fn create_option_with_vals1() {
+        let a = Arg::from_usage("-o <file> <mode> 'some help info'");
+        assert_eq!(a.name, "o");
+        assert!(a.long.is_none());
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"file", &"mode"]);
+    }
+
+    #[test]
+    fn create_option_with_vals2() {
+        let a = Arg::from_usage("-o <file> <mode>... 'some help info'");
+        assert_eq!(a.name, "o");
+        assert!(a.long.is_none());
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"file", &"mode"]);
+    }
+
+    #[test]
+    fn create_option_with_vals3() {
+        let a = Arg::from_usage("--opt <file> <mode>... 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"file", &"mode"]);
+    }
+
+    #[test]
+    fn create_option_with_vals4() {
+        let a = Arg::from_usage("[myopt] --opt <file> <mode> 'some help info'");
+        assert_eq!(a.name, "myopt");
+        assert!(a.short.is_none());
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"file", &"mode"]);
+    }
+
+    #[test]
+    fn create_option_with_vals5() {
+        let a = Arg::from_usage("--opt <file> <mode> 'some help info'");
+        assert_eq!(a.name, "opt");
+        assert!(a.short.is_none());
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+    }
+
+    #[test]
+    fn create_positional_usage() {
+        let a = Arg::from_usage("[pos] 'some help info'");
+        assert_eq!(a.name, "pos");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(!a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn create_positional_usage0() {
+        let a = Arg::from_usage("<pos> 'some help info'");
+        assert_eq!(a.name, "pos");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn pos_mult_help() {
+        let a = Arg::from_usage("[pos]... 'some help info'");
+        assert_eq!(a.name, "pos");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(!a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn pos_help_lit_single_quote() {
+        let a = Arg::from_usage("[pos]... 'some help\' info'");
+        assert_eq!(a.name, "pos");
+        assert_eq!(a.help.unwrap(), "some help' info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(!a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn pos_help_double_lit_single_quote() {
+        let a = Arg::from_usage("[pos]... 'some \'help\' info'");
+        assert_eq!(a.name, "pos");
+        assert_eq!(a.help.unwrap(), "some 'help' info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(!a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn pos_help_newline() {
+        let a = Arg::from_usage(
+            "[pos]... 'some help{n}\
+             info'",
+        );
+        assert_eq!(a.name, "pos");
+        assert_eq!(a.help.unwrap(), "some help{n}info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(!a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn pos_help_newline_lit_sq() {
+        let a = Arg::from_usage(
+            "[pos]... 'some help\' stuff{n}\
+             info'",
+        );
+        assert_eq!(a.name, "pos");
+        assert_eq!(a.help.unwrap(), "some help' stuff{n}info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(!a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn pos_req_mult_help() {
+        let a = Arg::from_usage("<pos>... 'some help info'");
+        assert_eq!(a.name, "pos");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn pos_req() {
+        let a = Arg::from_usage("<pos>");
+        assert_eq!(a.name, "pos");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn pos_mult() {
+        let a = Arg::from_usage("[pos]...");
+        assert_eq!(a.name, "pos");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(!a.is_required_set());
+        assert!(a.val_names.is_empty());
+    }
+
+    #[test]
+    fn pos_req_mult_def_help() {
+        let a = Arg::from_usage("<pos>... @a 'some help info'");
+        assert_eq!(a.name, "pos");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_required_set());
+        assert!(a.val_names.is_empty());
+        assert_eq!(a.default_vals, vec![std::ffi::OsStr::new("a")]);
+    }
+
+    #[test]
+    fn create_option_with_vals1_def() {
+        let a = Arg::from_usage("-o <file> <mode> @a 'some help info'");
+        assert_eq!(a.name, "o");
+        assert!(a.long.is_none());
+        assert_eq!(a.short.unwrap(), 'o');
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"file", &"mode"]);
+        assert_eq!(a.default_vals, vec![std::ffi::OsStr::new("a")]);
+    }
+
+    #[test]
+    fn create_option_with_vals4_def() {
+        let a = Arg::from_usage("[myopt] --opt <file> <mode> @a 'some help info'");
+        assert_eq!(a.name, "myopt");
+        assert!(a.short.is_none());
+        assert_eq!(a.long.unwrap(), "opt");
+        assert_eq!(a.help.unwrap(), "some help info");
+        assert!(!a.is_multiple_occurrences_set());
+        assert!(!a.is_multiple_values_set());
+        assert!(a.is_takes_value_set());
+        assert!(!a.is_required_set());
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"file", &"mode"]);
+        assert_eq!(a.default_vals, vec![std::ffi::OsStr::new("a")]);
+    }
+
+    #[test]
+    fn nonascii() {
+        let a = Arg::from_usage("<ASCII> 'üñíčöĐ€'");
+        assert_eq!(a.name, "ASCII");
+        assert_eq!(a.help, Some("üñíčöĐ€"));
+        let a = Arg::from_usage("<üñíčöĐ€> 'ASCII'");
+        assert_eq!(a.name, "üñíčöĐ€");
+        assert_eq!(a.help, Some("ASCII"));
+        let a = Arg::from_usage("<üñíčöĐ€> 'üñíčöĐ€'");
+        assert_eq!(a.name, "üñíčöĐ€");
+        assert_eq!(a.help, Some("üñíčöĐ€"));
+        let a = Arg::from_usage("-ø 'ø'");
+        assert_eq!(a.name, "ø");
+        assert_eq!(a.short, Some('ø'));
+        assert_eq!(a.help, Some("ø"));
+        let a = Arg::from_usage("--üñíčöĐ€ 'Nōṫ ASCII'");
+        assert_eq!(a.name, "üñíčöĐ€");
+        assert_eq!(a.long, Some("üñíčöĐ€"));
+        assert_eq!(a.help, Some("Nōṫ ASCII"));
+        let a = Arg::from_usage("[ñämê] --ôpt=[üñíčöĐ€] 'hælp'");
+        assert_eq!(a.name, "ñämê");
+        assert_eq!(a.long, Some("ôpt"));
+        assert_eq!(a.val_names.iter().collect::<Vec<_>>(), [&"üñíčöĐ€"]);
+        assert_eq!(a.help, Some("hælp"));
+    }
+
+    #[test]
+    fn value_names_building_num_vals_from_usage() {
+        use crate::Command;
+        let m = Command::new("test")
+            .arg(Arg::from_usage("--pos <who> <what> <why>"))
+            .try_get_matches_from(vec!["myprog", "--pos", "val1", "val2", "val3"]);
+
+        assert!(m.is_ok(), "{:?}", m.unwrap_err().kind());
+        let m = m.unwrap();
+
+        assert_eq!(
+            m.values_of("pos").unwrap().collect::<Vec<_>>(),
+            ["val1", "val2", "val3"]
+        );
+    }
+
+    #[test]
+    fn issue_665() {
+        use crate::{error::ErrorKind, Command};
+        // Verify fix for "arg_from_usage(): required values not being enforced when followed by another option"
+        let res = Command::new("tester")
+        .arg(Arg::from_usage("-v, --reroll-count=[N] 'Mark the patch series as PATCH vN'"))
+        .arg(
+            Arg::from_usage("--subject-prefix [Subject-Prefix] 'Use [Subject-Prefix] instead of the standard [PATCH] prefix'")
+                .setting(ArgSettings::ForbidEmptyValues)
+        )
+        .try_get_matches_from(vec!["test", "--subject-prefix", "-v", "2"]);
+
+        assert!(res.is_err());
+        assert_eq!(res.unwrap_err().kind(), ErrorKind::EmptyValue);
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/value_hint.rs b/vendor/clap-3.2.20/src/builder/value_hint.rs
new file mode 100644
index 000000000..7c35d1eb3
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/value_hint.rs
@@ -0,0 +1,95 @@
+use std::str::FromStr;
+
+/// Provide shell with hint on how to complete an argument.
+///
+/// See [Arg::value_hint][crate::Arg::value_hint] to set this on an argument.
+///
+/// See the `clap_complete` crate for completion script generation.
+///
+/// Overview of which hints are supported by which shell:
+///
+/// | Hint                   | zsh | fish[^1]|
+/// | ---------------------- | --- | ------- |
+/// | `AnyPath`              | Yes | Yes     |
+/// | `FilePath`             | Yes | Yes     |
+/// | `DirPath`              | Yes | Yes     |
+/// | `ExecutablePath`       | Yes | Partial |
+/// | `CommandName`          | Yes | Yes     |
+/// | `CommandString`        | Yes | Partial |
+/// | `CommandWithArguments` | Yes |         |
+/// | `Username`             | Yes | Yes     |
+/// | `Hostname`             | Yes | Yes     |
+/// | `Url`                  | Yes |         |
+/// | `EmailAddress`         | Yes |         |
+///
+/// [^1]: fish completions currently only support named arguments (e.g. -o or --opt), not
+///       positional arguments.
+#[derive(Debug, PartialEq, Eq, Hash, Copy, Clone)]
+#[non_exhaustive]
+pub enum ValueHint {
+    /// Default value if hint is not specified. Follows shell default behavior, which is usually
+    /// auto-completing filenames.
+    Unknown,
+    /// None of the hints below apply. Disables shell completion for this argument.
+    Other,
+    /// Any existing path.
+    AnyPath,
+    /// Path to a file.
+    FilePath,
+    /// Path to a directory.
+    DirPath,
+    /// Path to an executable file.
+    ExecutablePath,
+    /// Name of a command, without arguments. May be relative to PATH, or full path to executable.
+    CommandName,
+    /// A single string containing a command and its arguments.
+    CommandString,
+    /// Capture the remaining arguments as a command name and arguments for that command. This is
+    /// common when writing shell wrappers that execute anther command, for example `sudo` or `env`.
+    ///
+    /// This hint is special, the argument must be a positional argument and have
+    /// [`.multiple_values(true)`] and Command must use [`Command::trailing_var_arg(true)`]. The result is that the
+    /// command line `my_app ls -la /` will be parsed as `["ls", "-la", "/"]` and clap won't try to
+    /// parse the `-la` argument itself.
+    ///
+    /// [`Command::trailing_var_arg(true)`]: crate::Command::trailing_var_arg
+    /// [`.multiple_values(true)`]: crate::Arg::multiple_values()
+    CommandWithArguments,
+    /// Name of a local operating system user.
+    Username,
+    /// Host name of a computer.
+    /// Shells usually parse `/etc/hosts` and `.ssh/known_hosts` to complete hostnames.
+    Hostname,
+    /// Complete web address.
+    Url,
+    /// Email address.
+    EmailAddress,
+}
+
+impl Default for ValueHint {
+    fn default() -> Self {
+        ValueHint::Unknown
+    }
+}
+
+impl FromStr for ValueHint {
+    type Err = String;
+    fn from_str(s: &str) -> Result<Self, <Self as FromStr>::Err> {
+        Ok(match &*s.to_ascii_lowercase() {
+            "unknown" => ValueHint::Unknown,
+            "other" => ValueHint::Other,
+            "anypath" => ValueHint::AnyPath,
+            "filepath" => ValueHint::FilePath,
+            "dirpath" => ValueHint::DirPath,
+            "executablepath" => ValueHint::ExecutablePath,
+            "commandname" => ValueHint::CommandName,
+            "commandstring" => ValueHint::CommandString,
+            "commandwitharguments" => ValueHint::CommandWithArguments,
+            "username" => ValueHint::Username,
+            "hostname" => ValueHint::Hostname,
+            "url" => ValueHint::Url,
+            "emailaddress" => ValueHint::EmailAddress,
+            _ => return Err(format!("unknown ValueHint: `{}`", s)),
+        })
+    }
+}
diff --git a/vendor/clap-3.2.20/src/builder/value_parser.rs b/vendor/clap-3.2.20/src/builder/value_parser.rs
new file mode 100644
index 000000000..0492f2782
--- /dev/null
+++ b/vendor/clap-3.2.20/src/builder/value_parser.rs
@@ -0,0 +1,2089 @@
+use std::convert::TryInto;
+use std::ops::RangeBounds;
+
+use crate::parser::AnyValue;
+use crate::parser::AnyValueId;
+
+/// Parse/validate argument values
+///
+/// Specified with [`Arg::value_parser`][crate::Arg::value_parser].
+///
+/// `ValueParser` defines how to convert a raw argument value into a validated and typed value for
+/// use within an application.
+///
+/// See
+/// - [`value_parser!`][crate::value_parser] for automatically selecting an implementation for a given type
+/// - [`ValueParser::new`] for additional [`TypedValueParser`] that can be used
+///
+/// # Example
+///
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("color")
+///             .long("color")
+///             .value_parser(["always", "auto", "never"])
+///             .default_value("auto")
+///     )
+///     .arg(
+///         clap::Arg::new("hostname")
+///             .long("hostname")
+///             .value_parser(clap::builder::NonEmptyStringValueParser::new())
+///             .takes_value(true)
+///             .required(true)
+///     )
+///     .arg(
+///         clap::Arg::new("port")
+///             .long("port")
+///             .value_parser(clap::value_parser!(u16).range(3000..))
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(
+///     ["cmd", "--hostname", "rust-lang.org", "--port", "3001"]
+/// ).unwrap();
+///
+/// let color: &String = m.get_one("color")
+///     .expect("default");
+/// assert_eq!(color, "auto");
+///
+/// let hostname: &String = m.get_one("hostname")
+///     .expect("required");
+/// assert_eq!(hostname, "rust-lang.org");
+///
+/// let port: u16 = *m.get_one("port")
+///     .expect("required");
+/// assert_eq!(port, 3001);
+/// ```
+pub struct ValueParser(ValueParserInner);
+
+enum ValueParserInner {
+    // Common enough to optimize and for possible values
+    Bool,
+    // Common enough to optimize
+    String,
+    // Common enough to optimize
+    OsString,
+    // Common enough to optimize
+    PathBuf,
+    Other(Box<dyn AnyValueParser>),
+}
+
+impl ValueParser {
+    /// Custom parser for argument values
+    ///
+    /// To create a custom parser, see [`TypedValueParser`]
+    ///
+    /// Pre-existing implementations include:
+    /// - [`EnumValueParser`] and  [`PossibleValuesParser`] for static enumerated values
+    /// - [`BoolishValueParser`] and [`FalseyValueParser`] for alternative `bool` implementations
+    /// - [`RangedI64ValueParser`] and [`RangedU64ValueParser`]
+    /// - [`NonEmptyStringValueParser`]
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// type EnvVar = (String, Option<String>);
+    /// fn parse_env_var(env: &str) -> Result<EnvVar, std::io::Error> {
+    ///     if let Some((var, value)) = env.split_once('=') {
+    ///         Ok((var.to_owned(), Some(value.to_owned())))
+    ///     } else {
+    ///         Ok((env.to_owned(), None))
+    ///     }
+    /// }
+    ///
+    /// let mut cmd = clap::Command::new("raw")
+    ///     .arg(
+    ///         clap::Arg::new("env")
+    ///             .value_parser(clap::builder::ValueParser::new(parse_env_var))
+    ///             .required(true)
+    ///     );
+    ///
+    /// let m = cmd.try_get_matches_from_mut(["cmd", "key=value"]).unwrap();
+    /// let port: &EnvVar = m.get_one("env")
+    ///     .expect("required");
+    /// assert_eq!(*port, ("key".into(), Some("value".into())));
+    /// ```
+    pub fn new<P>(other: P) -> Self
+    where
+        P: TypedValueParser,
+        P::Value: Send + Sync + Clone,
+    {
+        Self(ValueParserInner::Other(Box::new(other)))
+    }
+
+    /// [`bool`] parser for argument values
+    ///
+    /// See also:
+    /// - [`BoolishValueParser`] for different human readable bool representations
+    /// - [`FalseyValueParser`] for assuming non-false is true
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// let mut cmd = clap::Command::new("raw")
+    ///     .arg(
+    ///         clap::Arg::new("download")
+    ///             .value_parser(clap::value_parser!(bool))
+    ///             .required(true)
+    ///     );
+    ///
+    /// let m = cmd.try_get_matches_from_mut(["cmd", "true"]).unwrap();
+    /// let port: bool = *m.get_one("download")
+    ///     .expect("required");
+    /// assert_eq!(port, true);
+    ///
+    /// assert!(cmd.try_get_matches_from_mut(["cmd", "forever"]).is_err());
+    /// ```
+    pub const fn bool() -> Self {
+        Self(ValueParserInner::Bool)
+    }
+
+    /// [`String`] parser for argument values
+    ///
+    /// See also:
+    /// - [`NonEmptyStringValueParser`]
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// let mut cmd = clap::Command::new("raw")
+    ///     .arg(
+    ///         clap::Arg::new("port")
+    ///             .value_parser(clap::value_parser!(String))
+    ///             .required(true)
+    ///     );
+    ///
+    /// let m = cmd.try_get_matches_from_mut(["cmd", "80"]).unwrap();
+    /// let port: &String = m.get_one("port")
+    ///     .expect("required");
+    /// assert_eq!(port, "80");
+    /// ```
+    pub const fn string() -> Self {
+        Self(ValueParserInner::String)
+    }
+
+    /// [`OsString`][std::ffi::OsString] parser for argument values
+    ///
+    /// # Example
+    ///
+    #[cfg_attr(not(unix), doc = " ```ignore")]
+    #[cfg_attr(unix, doc = " ```rust")]
+    /// # use clap::{Command, Arg, builder::ValueParser};
+    /// use std::ffi::OsString;
+    /// use std::os::unix::ffi::{OsStrExt,OsStringExt};
+    /// let r = Command::new("myprog")
+    ///     .arg(
+    ///         Arg::new("arg")
+    ///         .required(true)
+    ///         .value_parser(ValueParser::os_string())
+    ///     )
+    ///     .try_get_matches_from(vec![
+    ///         OsString::from("myprog"),
+    ///         OsString::from_vec(vec![0xe9])
+    ///     ]);
+    ///
+    /// assert!(r.is_ok());
+    /// let m = r.unwrap();
+    /// let arg: &OsString = m.get_one("arg")
+    ///     .expect("required");
+    /// assert_eq!(arg.as_bytes(), &[0xe9]);
+    /// ```
+    pub const fn os_string() -> Self {
+        Self(ValueParserInner::OsString)
+    }
+
+    /// [`PathBuf`][std::path::PathBuf] parser for argument values
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// # use std::path::PathBuf;
+    /// # use std::path::Path;
+    /// let mut cmd = clap::Command::new("raw")
+    ///     .arg(
+    ///         clap::Arg::new("output")
+    ///             .value_parser(clap::value_parser!(PathBuf))
+    ///             .required(true)
+    ///     );
+    ///
+    /// let m = cmd.try_get_matches_from_mut(["cmd", "hello.txt"]).unwrap();
+    /// let port: &PathBuf = m.get_one("output")
+    ///     .expect("required");
+    /// assert_eq!(port, Path::new("hello.txt"));
+    ///
+    /// assert!(cmd.try_get_matches_from_mut(["cmd", ""]).is_err());
+    /// ```
+    pub const fn path_buf() -> Self {
+        Self(ValueParserInner::PathBuf)
+    }
+}
+
+impl ValueParser {
+    /// Parse into a `AnyValue`
+    ///
+    /// When `arg` is `None`, an external subcommand value is being parsed.
+    pub(crate) fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<AnyValue, crate::Error> {
+        self.any_value_parser().parse_ref(cmd, arg, value)
+    }
+
+    /// Describes the content of `AnyValue`
+    pub fn type_id(&self) -> AnyValueId {
+        self.any_value_parser().type_id()
+    }
+
+    /// Reflect on enumerated value properties
+    ///
+    /// Error checking should not be done with this; it is mostly targeted at user-facing
+    /// applications like errors and completion.
+    pub fn possible_values(
+        &self,
+    ) -> Option<Box<dyn Iterator<Item = crate::PossibleValue<'static>> + '_>> {
+        self.any_value_parser().possible_values()
+    }
+
+    fn any_value_parser(&self) -> &dyn AnyValueParser {
+        match &self.0 {
+            ValueParserInner::Bool => &BoolValueParser {},
+            ValueParserInner::String => &StringValueParser {},
+            ValueParserInner::OsString => &OsStringValueParser {},
+            ValueParserInner::PathBuf => &PathBufValueParser {},
+            ValueParserInner::Other(o) => o.as_ref(),
+        }
+    }
+}
+
+/// Convert a [`TypedValueParser`] to [`ValueParser`]
+///
+/// # Example
+///
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("hostname")
+///             .long("hostname")
+///             .value_parser(clap::builder::NonEmptyStringValueParser::new())
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(
+///     ["cmd", "--hostname", "rust-lang.org"]
+/// ).unwrap();
+///
+/// let hostname: &String = m.get_one("hostname")
+///     .expect("required");
+/// assert_eq!(hostname, "rust-lang.org");
+/// ```
+impl<P> From<P> for ValueParser
+where
+    P: TypedValueParser + Send + Sync + 'static,
+    P::Value: Send + Sync + Clone,
+{
+    fn from(p: P) -> Self {
+        Self::new(p)
+    }
+}
+
+impl From<_AnonymousValueParser> for ValueParser {
+    fn from(p: _AnonymousValueParser) -> Self {
+        p.0
+    }
+}
+
+/// Create an `i64` [`ValueParser`] from a `N..M` range
+///
+/// See [`RangedI64ValueParser`] for more control over the output type.
+///
+/// See also [`RangedU64ValueParser`]
+///
+/// # Examples
+///
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("port")
+///             .long("port")
+///             .value_parser(3000..4000)
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "--port", "3001"]).unwrap();
+/// let port: i64 = *m.get_one("port")
+///     .expect("required");
+/// assert_eq!(port, 3001);
+/// ```
+impl From<std::ops::Range<i64>> for ValueParser {
+    fn from(value: std::ops::Range<i64>) -> Self {
+        let inner = RangedI64ValueParser::<i64>::new().range(value.start..value.end);
+        Self::from(inner)
+    }
+}
+
+/// Create an `i64` [`ValueParser`] from a `N..=M` range
+///
+/// See [`RangedI64ValueParser`] for more control over the output type.
+///
+/// See also [`RangedU64ValueParser`]
+///
+/// # Examples
+///
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("port")
+///             .long("port")
+///             .value_parser(3000..=4000)
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "--port", "3001"]).unwrap();
+/// let port: i64 = *m.get_one("port")
+///     .expect("required");
+/// assert_eq!(port, 3001);
+/// ```
+impl From<std::ops::RangeInclusive<i64>> for ValueParser {
+    fn from(value: std::ops::RangeInclusive<i64>) -> Self {
+        let inner = RangedI64ValueParser::<i64>::new().range(value.start()..=value.end());
+        Self::from(inner)
+    }
+}
+
+/// Create an `i64` [`ValueParser`] from a `N..` range
+///
+/// See [`RangedI64ValueParser`] for more control over the output type.
+///
+/// See also [`RangedU64ValueParser`]
+///
+/// # Examples
+///
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("port")
+///             .long("port")
+///             .value_parser(3000..)
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "--port", "3001"]).unwrap();
+/// let port: i64 = *m.get_one("port")
+///     .expect("required");
+/// assert_eq!(port, 3001);
+/// ```
+impl From<std::ops::RangeFrom<i64>> for ValueParser {
+    fn from(value: std::ops::RangeFrom<i64>) -> Self {
+        let inner = RangedI64ValueParser::<i64>::new().range(value.start..);
+        Self::from(inner)
+    }
+}
+
+/// Create an `i64` [`ValueParser`] from a `..M` range
+///
+/// See [`RangedI64ValueParser`] for more control over the output type.
+///
+/// See also [`RangedU64ValueParser`]
+///
+/// # Examples
+///
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("port")
+///             .long("port")
+///             .value_parser(..3000)
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "--port", "80"]).unwrap();
+/// let port: i64 = *m.get_one("port")
+///     .expect("required");
+/// assert_eq!(port, 80);
+/// ```
+impl From<std::ops::RangeTo<i64>> for ValueParser {
+    fn from(value: std::ops::RangeTo<i64>) -> Self {
+        let inner = RangedI64ValueParser::<i64>::new().range(..value.end);
+        Self::from(inner)
+    }
+}
+
+/// Create an `i64` [`ValueParser`] from a `..=M` range
+///
+/// See [`RangedI64ValueParser`] for more control over the output type.
+///
+/// See also [`RangedU64ValueParser`]
+///
+/// # Examples
+///
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("port")
+///             .long("port")
+///             .value_parser(..=3000)
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "--port", "80"]).unwrap();
+/// let port: i64 = *m.get_one("port")
+///     .expect("required");
+/// assert_eq!(port, 80);
+/// ```
+impl From<std::ops::RangeToInclusive<i64>> for ValueParser {
+    fn from(value: std::ops::RangeToInclusive<i64>) -> Self {
+        let inner = RangedI64ValueParser::<i64>::new().range(..=value.end);
+        Self::from(inner)
+    }
+}
+
+/// Create an `i64` [`ValueParser`] from a `..` range
+///
+/// See [`RangedI64ValueParser`] for more control over the output type.
+///
+/// See also [`RangedU64ValueParser`]
+///
+/// # Examples
+///
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("port")
+///             .long("port")
+///             .value_parser(..)
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "--port", "3001"]).unwrap();
+/// let port: i64 = *m.get_one("port")
+///     .expect("required");
+/// assert_eq!(port, 3001);
+/// ```
+impl From<std::ops::RangeFull> for ValueParser {
+    fn from(value: std::ops::RangeFull) -> Self {
+        let inner = RangedI64ValueParser::<i64>::new().range(value);
+        Self::from(inner)
+    }
+}
+
+/// Create a [`ValueParser`] with [`PossibleValuesParser`]
+///
+/// See [`PossibleValuesParser`] for more flexibility in creating the
+/// [`PossibleValue`][crate::PossibleValue]s.
+///
+/// # Examples
+///
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("color")
+///             .long("color")
+///             .value_parser(["always", "auto", "never"])
+///             .default_value("auto")
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(
+///     ["cmd", "--color", "never"]
+/// ).unwrap();
+///
+/// let color: &String = m.get_one("color")
+///     .expect("default");
+/// assert_eq!(color, "never");
+/// ```
+impl<P, const C: usize> From<[P; C]> for ValueParser
+where
+    P: Into<super::PossibleValue<'static>>,
+{
+    fn from(values: [P; C]) -> Self {
+        let inner = PossibleValuesParser::from(values);
+        Self::from(inner)
+    }
+}
+
+impl std::fmt::Debug for ValueParser {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
+        match &self.0 {
+            ValueParserInner::Bool => f.debug_struct("ValueParser::bool").finish(),
+            ValueParserInner::String => f.debug_struct("ValueParser::string").finish(),
+            ValueParserInner::OsString => f.debug_struct("ValueParser::os_string").finish(),
+            ValueParserInner::PathBuf => f.debug_struct("ValueParser::path_buf").finish(),
+            ValueParserInner::Other(o) => write!(f, "ValueParser::other({:?})", o.type_id()),
+        }
+    }
+}
+
+impl Clone for ValueParser {
+    fn clone(&self) -> Self {
+        Self(match &self.0 {
+            ValueParserInner::Bool => ValueParserInner::Bool,
+            ValueParserInner::String => ValueParserInner::String,
+            ValueParserInner::OsString => ValueParserInner::OsString,
+            ValueParserInner::PathBuf => ValueParserInner::PathBuf,
+            ValueParserInner::Other(o) => ValueParserInner::Other(o.clone_any()),
+        })
+    }
+}
+
+/// A type-erased wrapper for [`TypedValueParser`].
+trait AnyValueParser: Send + Sync + 'static {
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<AnyValue, crate::Error>;
+
+    fn parse(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: std::ffi::OsString,
+    ) -> Result<AnyValue, crate::Error>;
+
+    /// Describes the content of `AnyValue`
+    fn type_id(&self) -> AnyValueId;
+
+    fn possible_values(
+        &self,
+    ) -> Option<Box<dyn Iterator<Item = crate::PossibleValue<'static>> + '_>>;
+
+    fn clone_any(&self) -> Box<dyn AnyValueParser>;
+}
+
+impl<T, P> AnyValueParser for P
+where
+    T: std::any::Any + Clone + Send + Sync + 'static,
+    P: TypedValueParser<Value = T>,
+{
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<AnyValue, crate::Error> {
+        let value = TypedValueParser::parse_ref(self, cmd, arg, value)?;
+        Ok(AnyValue::new(value))
+    }
+
+    fn parse(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: std::ffi::OsString,
+    ) -> Result<AnyValue, crate::Error> {
+        let value = TypedValueParser::parse(self, cmd, arg, value)?;
+        Ok(AnyValue::new(value))
+    }
+
+    fn type_id(&self) -> AnyValueId {
+        AnyValueId::of::<T>()
+    }
+
+    fn possible_values(
+        &self,
+    ) -> Option<Box<dyn Iterator<Item = crate::PossibleValue<'static>> + '_>> {
+        P::possible_values(self)
+    }
+
+    fn clone_any(&self) -> Box<dyn AnyValueParser> {
+        Box::new(self.clone())
+    }
+}
+
+/// Parse/validate argument values
+pub trait TypedValueParser: Clone + Send + Sync + 'static {
+    /// Argument's value type
+    type Value;
+
+    /// Parse the argument value
+    ///
+    /// When `arg` is `None`, an external subcommand value is being parsed.
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error>;
+
+    /// Parse the argument value
+    ///
+    /// When `arg` is `None`, an external subcommand value is being parsed.
+    fn parse(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: std::ffi::OsString,
+    ) -> Result<Self::Value, crate::Error> {
+        self.parse_ref(cmd, arg, &value)
+    }
+
+    /// Reflect on enumerated value properties
+    ///
+    /// Error checking should not be done with this; it is mostly targeted at user-facing
+    /// applications like errors and completion.
+    fn possible_values(
+        &self,
+    ) -> Option<Box<dyn Iterator<Item = crate::PossibleValue<'static>> + '_>> {
+        None
+    }
+}
+
+impl<F, T, E> TypedValueParser for F
+where
+    F: Fn(&str) -> Result<T, E> + Clone + Send + Sync + 'static,
+    E: Into<Box<dyn std::error::Error + Send + Sync + 'static>>,
+{
+    type Value = T;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        let value = value.to_str().ok_or_else(|| {
+            crate::Error::invalid_utf8(
+                cmd,
+                crate::output::Usage::new(cmd).create_usage_with_title(&[]),
+            )
+        })?;
+        let value = (self)(value).map_err(|e| {
+            let arg = arg
+                .map(|a| a.to_string())
+                .unwrap_or_else(|| "...".to_owned());
+            crate::Error::value_validation(arg, value.to_owned(), e.into()).with_cmd(cmd)
+        })?;
+        Ok(value)
+    }
+}
+
+/// Implementation for [`ValueParser::string`]
+///
+/// Useful for composing new [`TypedValueParser`]s
+#[derive(Copy, Clone, Debug)]
+#[non_exhaustive]
+pub struct StringValueParser {}
+
+impl StringValueParser {
+    /// Implementation for [`ValueParser::string`]
+    pub fn new() -> Self {
+        Self {}
+    }
+}
+
+impl TypedValueParser for StringValueParser {
+    type Value = String;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        TypedValueParser::parse(self, cmd, arg, value.to_owned())
+    }
+
+    fn parse(
+        &self,
+        cmd: &crate::Command,
+        _arg: Option<&crate::Arg>,
+        value: std::ffi::OsString,
+    ) -> Result<Self::Value, crate::Error> {
+        let value = value.into_string().map_err(|_| {
+            crate::Error::invalid_utf8(
+                cmd,
+                crate::output::Usage::new(cmd).create_usage_with_title(&[]),
+            )
+        })?;
+        Ok(value)
+    }
+}
+
+impl Default for StringValueParser {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Implementation for [`ValueParser::os_string`]
+///
+/// Useful for composing new [`TypedValueParser`]s
+#[derive(Copy, Clone, Debug)]
+#[non_exhaustive]
+pub struct OsStringValueParser {}
+
+impl OsStringValueParser {
+    /// Implementation for [`ValueParser::os_string`]
+    pub fn new() -> Self {
+        Self {}
+    }
+}
+
+impl TypedValueParser for OsStringValueParser {
+    type Value = std::ffi::OsString;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        TypedValueParser::parse(self, cmd, arg, value.to_owned())
+    }
+
+    fn parse(
+        &self,
+        _cmd: &crate::Command,
+        _arg: Option<&crate::Arg>,
+        value: std::ffi::OsString,
+    ) -> Result<Self::Value, crate::Error> {
+        Ok(value)
+    }
+}
+
+impl Default for OsStringValueParser {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Implementation for [`ValueParser::path_buf`]
+///
+/// Useful for composing new [`TypedValueParser`]s
+#[derive(Copy, Clone, Debug)]
+#[non_exhaustive]
+pub struct PathBufValueParser {}
+
+impl PathBufValueParser {
+    /// Implementation for [`ValueParser::path_buf`]
+    pub fn new() -> Self {
+        Self {}
+    }
+}
+
+impl TypedValueParser for PathBufValueParser {
+    type Value = std::path::PathBuf;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        TypedValueParser::parse(self, cmd, arg, value.to_owned())
+    }
+
+    fn parse(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: std::ffi::OsString,
+    ) -> Result<Self::Value, crate::Error> {
+        if value.is_empty() {
+            return Err(crate::Error::empty_value(
+                cmd,
+                &[],
+                arg.map(ToString::to_string)
+                    .unwrap_or_else(|| "...".to_owned()),
+            ));
+        }
+        Ok(Self::Value::from(value))
+    }
+}
+
+impl Default for PathBufValueParser {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Parse an [`ValueEnum`][crate::ValueEnum] value.
+///
+/// See also:
+/// - [`PossibleValuesParser`]
+///
+/// # Example
+///
+/// ```rust
+/// # use std::ffi::OsStr;
+/// # use clap::builder::TypedValueParser;
+/// # let cmd = clap::Command::new("test");
+/// # let arg = None;
+///
+/// #[derive(Copy, Clone, Debug, PartialEq, Eq)]
+/// enum ColorChoice {
+///     Always,
+///     Auto,
+///     Never,
+/// }
+///
+/// impl clap::ValueEnum for ColorChoice {
+///     fn value_variants<'a>() -> &'a [Self] {
+///         &[Self::Always, Self::Auto, Self::Never]
+///     }
+///
+///     fn to_possible_value<'a>(&self) -> Option<clap::PossibleValue<'a>> {
+///         match self {
+///             Self::Always => Some(clap::PossibleValue::new("always")),
+///             Self::Auto => Some(clap::PossibleValue::new("auto")),
+///             Self::Never => Some(clap::PossibleValue::new("never")),
+///         }
+///     }
+/// }
+///
+/// // Usage
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("color")
+///             .value_parser(clap::builder::EnumValueParser::<ColorChoice>::new())
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "always"]).unwrap();
+/// let port: ColorChoice = *m.get_one("color")
+///     .expect("required");
+/// assert_eq!(port, ColorChoice::Always);
+///
+/// // Semantics
+/// let value_parser = clap::builder::EnumValueParser::<ColorChoice>::new();
+/// // or
+/// let value_parser = clap::value_parser!(ColorChoice);
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("random")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("")).is_err());
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("always")).unwrap(), ColorChoice::Always);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("auto")).unwrap(), ColorChoice::Auto);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("never")).unwrap(), ColorChoice::Never);
+/// ```
+#[derive(Clone, Debug)]
+pub struct EnumValueParser<E: crate::ValueEnum + Clone + Send + Sync + 'static>(
+    std::marker::PhantomData<E>,
+);
+
+impl<E: crate::ValueEnum + Clone + Send + Sync + 'static> EnumValueParser<E> {
+    /// Parse an [`ValueEnum`][crate::ValueEnum]
+    pub fn new() -> Self {
+        let phantom: std::marker::PhantomData<E> = Default::default();
+        Self(phantom)
+    }
+}
+
+impl<E: crate::ValueEnum + Clone + Send + Sync + 'static> TypedValueParser for EnumValueParser<E> {
+    type Value = E;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        let ignore_case = arg.map(|a| a.is_ignore_case_set()).unwrap_or(false);
+        let possible_vals = || {
+            E::value_variants()
+                .iter()
+                .filter_map(|v| v.to_possible_value())
+                .filter(|v| !v.is_hide_set())
+                .map(|v| v.get_name())
+                .collect::<Vec<_>>()
+        };
+
+        let value = value.to_str().ok_or_else(|| {
+            crate::Error::invalid_value(
+                cmd,
+                value.to_string_lossy().into_owned(),
+                &possible_vals(),
+                arg.map(ToString::to_string)
+                    .unwrap_or_else(|| "...".to_owned()),
+            )
+        })?;
+        let value = E::value_variants()
+            .iter()
+            .find(|v| {
+                v.to_possible_value()
+                    .expect("ValueEnum::value_variants contains only values with a corresponding ValueEnum::to_possible_value")
+                    .matches(value, ignore_case)
+            })
+            .ok_or_else(|| {
+            crate::Error::invalid_value(
+                cmd,
+                value.to_owned(),
+                &possible_vals(),
+                arg.map(ToString::to_string)
+                    .unwrap_or_else(|| "...".to_owned()),
+            )
+            })?
+            .clone();
+        Ok(value)
+    }
+
+    fn possible_values(
+        &self,
+    ) -> Option<Box<dyn Iterator<Item = crate::PossibleValue<'static>> + '_>> {
+        Some(Box::new(
+            E::value_variants()
+                .iter()
+                .filter_map(|v| v.to_possible_value()),
+        ))
+    }
+}
+
+impl<E: crate::ValueEnum + Clone + Send + Sync + 'static> Default for EnumValueParser<E> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Verify the value is from an enumerated set of [`PossibleValue`][crate::PossibleValue].
+///
+/// See also:
+/// - [`EnumValueParser`]
+///
+/// # Example
+///
+/// Usage:
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("color")
+///             .value_parser(clap::builder::PossibleValuesParser::new(["always", "auto", "never"]))
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "always"]).unwrap();
+/// let port: &String = m.get_one("color")
+///     .expect("required");
+/// assert_eq!(port, "always");
+/// ```
+///
+/// Semantics:
+/// ```rust
+/// # use std::ffi::OsStr;
+/// # use clap::builder::TypedValueParser;
+/// # let cmd = clap::Command::new("test");
+/// # let arg = None;
+/// let value_parser = clap::builder::PossibleValuesParser::new(["always", "auto", "never"]);
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("random")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("")).is_err());
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("always")).unwrap(), "always");
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("auto")).unwrap(), "auto");
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("never")).unwrap(), "never");
+/// ```
+#[derive(Clone, Debug)]
+pub struct PossibleValuesParser(Vec<super::PossibleValue<'static>>);
+
+impl PossibleValuesParser {
+    /// Verify the value is from an enumerated set pf [`PossibleValue`][crate::PossibleValue].
+    pub fn new(values: impl Into<PossibleValuesParser>) -> Self {
+        values.into()
+    }
+}
+
+impl TypedValueParser for PossibleValuesParser {
+    type Value = String;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        TypedValueParser::parse(self, cmd, arg, value.to_owned())
+    }
+
+    fn parse(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: std::ffi::OsString,
+    ) -> Result<String, crate::Error> {
+        let value = value.into_string().map_err(|_| {
+            crate::Error::invalid_utf8(
+                cmd,
+                crate::output::Usage::new(cmd).create_usage_with_title(&[]),
+            )
+        })?;
+
+        let ignore_case = arg.map(|a| a.is_ignore_case_set()).unwrap_or(false);
+        if self.0.iter().any(|v| v.matches(&value, ignore_case)) {
+            Ok(value)
+        } else {
+            let possible_vals = self
+                .0
+                .iter()
+                .filter(|v| !v.is_hide_set())
+                .map(crate::builder::PossibleValue::get_name)
+                .collect::<Vec<_>>();
+
+            Err(crate::Error::invalid_value(
+                cmd,
+                value,
+                &possible_vals,
+                arg.map(ToString::to_string)
+                    .unwrap_or_else(|| "...".to_owned()),
+            ))
+        }
+    }
+
+    fn possible_values(
+        &self,
+    ) -> Option<Box<dyn Iterator<Item = crate::PossibleValue<'static>> + '_>> {
+        Some(Box::new(self.0.iter().cloned()))
+    }
+}
+
+impl<I, T> From<I> for PossibleValuesParser
+where
+    I: IntoIterator<Item = T>,
+    T: Into<super::PossibleValue<'static>>,
+{
+    fn from(values: I) -> Self {
+        Self(values.into_iter().map(|t| t.into()).collect())
+    }
+}
+
+/// Parse number that fall within a range of values
+///
+/// # Example
+///
+/// Usage:
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("port")
+///             .long("port")
+///             .value_parser(clap::value_parser!(u16).range(3000..))
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "--port", "3001"]).unwrap();
+/// let port: u16 = *m.get_one("port")
+///     .expect("required");
+/// assert_eq!(port, 3001);
+/// ```
+///
+/// Semantics:
+/// ```rust
+/// # use std::ffi::OsStr;
+/// # use clap::builder::TypedValueParser;
+/// # let cmd = clap::Command::new("test");
+/// # let arg = None;
+/// let value_parser = clap::builder::RangedI64ValueParser::<i32>::new().range(-1..200);
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("random")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("-200")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("300")).is_err());
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("-1")).unwrap(), -1);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("0")).unwrap(), 0);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("50")).unwrap(), 50);
+/// ```
+#[derive(Copy, Clone, Debug)]
+pub struct RangedI64ValueParser<T: std::convert::TryFrom<i64> + Clone + Send + Sync = i64> {
+    bounds: (std::ops::Bound<i64>, std::ops::Bound<i64>),
+    target: std::marker::PhantomData<T>,
+}
+
+impl<T: std::convert::TryFrom<i64> + Clone + Send + Sync> RangedI64ValueParser<T> {
+    /// Select full range of `i64`
+    pub fn new() -> Self {
+        Self::from(..)
+    }
+
+    /// Narrow the supported range
+    pub fn range<B: RangeBounds<i64>>(mut self, range: B) -> Self {
+        // Consideration: when the user does `value_parser!(u8).range()`
+        // - Avoid programming mistakes by accidentally expanding the range
+        // - Make it convenient to limit the range like with `..10`
+        let start = match range.start_bound() {
+            l @ std::ops::Bound::Included(i) => {
+                debug_assert!(
+                    self.bounds.contains(i),
+                    "{} must be in {:?}",
+                    i,
+                    self.bounds
+                );
+                l.cloned()
+            }
+            l @ std::ops::Bound::Excluded(i) => {
+                debug_assert!(
+                    self.bounds.contains(&i.saturating_add(1)),
+                    "{} must be in {:?}",
+                    i,
+                    self.bounds
+                );
+                l.cloned()
+            }
+            std::ops::Bound::Unbounded => self.bounds.start_bound().cloned(),
+        };
+        let end = match range.end_bound() {
+            l @ std::ops::Bound::Included(i) => {
+                debug_assert!(
+                    self.bounds.contains(i),
+                    "{} must be in {:?}",
+                    i,
+                    self.bounds
+                );
+                l.cloned()
+            }
+            l @ std::ops::Bound::Excluded(i) => {
+                debug_assert!(
+                    self.bounds.contains(&i.saturating_sub(1)),
+                    "{} must be in {:?}",
+                    i,
+                    self.bounds
+                );
+                l.cloned()
+            }
+            std::ops::Bound::Unbounded => self.bounds.end_bound().cloned(),
+        };
+        self.bounds = (start, end);
+        self
+    }
+
+    fn format_bounds(&self) -> String {
+        let mut result = match self.bounds.0 {
+            std::ops::Bound::Included(i) => i.to_string(),
+            std::ops::Bound::Excluded(i) => i.saturating_add(1).to_string(),
+            std::ops::Bound::Unbounded => i64::MIN.to_string(),
+        };
+        result.push_str("..");
+        match self.bounds.1 {
+            std::ops::Bound::Included(i) => {
+                result.push('=');
+                result.push_str(&i.to_string());
+            }
+            std::ops::Bound::Excluded(i) => {
+                result.push_str(&i.to_string());
+            }
+            std::ops::Bound::Unbounded => {
+                result.push_str(&i64::MAX.to_string());
+            }
+        }
+        result
+    }
+}
+
+impl<T: std::convert::TryFrom<i64> + Clone + Send + Sync + 'static> TypedValueParser
+    for RangedI64ValueParser<T>
+where
+    <T as std::convert::TryFrom<i64>>::Error: Send + Sync + 'static + std::error::Error + ToString,
+{
+    type Value = T;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        raw_value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        let value = raw_value.to_str().ok_or_else(|| {
+            crate::Error::invalid_utf8(
+                cmd,
+                crate::output::Usage::new(cmd).create_usage_with_title(&[]),
+            )
+        })?;
+        let value = value.parse::<i64>().map_err(|err| {
+            let arg = arg
+                .map(|a| a.to_string())
+                .unwrap_or_else(|| "...".to_owned());
+            crate::Error::value_validation(
+                arg,
+                raw_value.to_string_lossy().into_owned(),
+                err.into(),
+            )
+            .with_cmd(cmd)
+        })?;
+        if !self.bounds.contains(&value) {
+            let arg = arg
+                .map(|a| a.to_string())
+                .unwrap_or_else(|| "...".to_owned());
+            return Err(crate::Error::value_validation(
+                arg,
+                raw_value.to_string_lossy().into_owned(),
+                format!("{} is not in {}", value, self.format_bounds()).into(),
+            )
+            .with_cmd(cmd));
+        }
+
+        let value: Result<Self::Value, _> = value.try_into();
+        let value = value.map_err(|err| {
+            let arg = arg
+                .map(|a| a.to_string())
+                .unwrap_or_else(|| "...".to_owned());
+            crate::Error::value_validation(
+                arg,
+                raw_value.to_string_lossy().into_owned(),
+                err.into(),
+            )
+            .with_cmd(cmd)
+        })?;
+
+        Ok(value)
+    }
+}
+
+impl<T: std::convert::TryFrom<i64> + Clone + Send + Sync, B: RangeBounds<i64>> From<B>
+    for RangedI64ValueParser<T>
+{
+    fn from(range: B) -> Self {
+        Self {
+            bounds: (range.start_bound().cloned(), range.end_bound().cloned()),
+            target: Default::default(),
+        }
+    }
+}
+
+impl<T: std::convert::TryFrom<i64> + Clone + Send + Sync> Default for RangedI64ValueParser<T> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Parse number that fall within a range of values
+///
+/// # Example
+///
+/// Usage:
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("port")
+///             .long("port")
+///             .value_parser(clap::value_parser!(u64).range(3000..))
+///             .takes_value(true)
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "--port", "3001"]).unwrap();
+/// let port: u64 = *m.get_one("port")
+///     .expect("required");
+/// assert_eq!(port, 3001);
+/// ```
+///
+/// Semantics:
+/// ```rust
+/// # use std::ffi::OsStr;
+/// # use clap::builder::TypedValueParser;
+/// # let cmd = clap::Command::new("test");
+/// # let arg = None;
+/// let value_parser = clap::builder::RangedU64ValueParser::<u32>::new().range(0..200);
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("random")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("-200")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("300")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("-1")).is_err());
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("0")).unwrap(), 0);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("50")).unwrap(), 50);
+/// ```
+#[derive(Copy, Clone, Debug)]
+pub struct RangedU64ValueParser<T: std::convert::TryFrom<u64> = u64> {
+    bounds: (std::ops::Bound<u64>, std::ops::Bound<u64>),
+    target: std::marker::PhantomData<T>,
+}
+
+impl<T: std::convert::TryFrom<u64>> RangedU64ValueParser<T> {
+    /// Select full range of `u64`
+    pub fn new() -> Self {
+        Self::from(..)
+    }
+
+    /// Narrow the supported range
+    pub fn range<B: RangeBounds<u64>>(mut self, range: B) -> Self {
+        // Consideration: when the user does `value_parser!(u8).range()`
+        // - Avoid programming mistakes by accidentally expanding the range
+        // - Make it convenient to limit the range like with `..10`
+        let start = match range.start_bound() {
+            l @ std::ops::Bound::Included(i) => {
+                debug_assert!(
+                    self.bounds.contains(i),
+                    "{} must be in {:?}",
+                    i,
+                    self.bounds
+                );
+                l.cloned()
+            }
+            l @ std::ops::Bound::Excluded(i) => {
+                debug_assert!(
+                    self.bounds.contains(&i.saturating_add(1)),
+                    "{} must be in {:?}",
+                    i,
+                    self.bounds
+                );
+                l.cloned()
+            }
+            std::ops::Bound::Unbounded => self.bounds.start_bound().cloned(),
+        };
+        let end = match range.end_bound() {
+            l @ std::ops::Bound::Included(i) => {
+                debug_assert!(
+                    self.bounds.contains(i),
+                    "{} must be in {:?}",
+                    i,
+                    self.bounds
+                );
+                l.cloned()
+            }
+            l @ std::ops::Bound::Excluded(i) => {
+                debug_assert!(
+                    self.bounds.contains(&i.saturating_sub(1)),
+                    "{} must be in {:?}",
+                    i,
+                    self.bounds
+                );
+                l.cloned()
+            }
+            std::ops::Bound::Unbounded => self.bounds.end_bound().cloned(),
+        };
+        self.bounds = (start, end);
+        self
+    }
+
+    fn format_bounds(&self) -> String {
+        let mut result = match self.bounds.0 {
+            std::ops::Bound::Included(i) => i.to_string(),
+            std::ops::Bound::Excluded(i) => i.saturating_add(1).to_string(),
+            std::ops::Bound::Unbounded => u64::MIN.to_string(),
+        };
+        result.push_str("..");
+        match self.bounds.1 {
+            std::ops::Bound::Included(i) => {
+                result.push('=');
+                result.push_str(&i.to_string());
+            }
+            std::ops::Bound::Excluded(i) => {
+                result.push_str(&i.to_string());
+            }
+            std::ops::Bound::Unbounded => {
+                result.push_str(&u64::MAX.to_string());
+            }
+        }
+        result
+    }
+}
+
+impl<T: std::convert::TryFrom<u64> + Clone + Send + Sync + 'static> TypedValueParser
+    for RangedU64ValueParser<T>
+where
+    <T as std::convert::TryFrom<u64>>::Error: Send + Sync + 'static + std::error::Error + ToString,
+{
+    type Value = T;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        raw_value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        let value = raw_value.to_str().ok_or_else(|| {
+            crate::Error::invalid_utf8(
+                cmd,
+                crate::output::Usage::new(cmd).create_usage_with_title(&[]),
+            )
+        })?;
+        let value = value.parse::<u64>().map_err(|err| {
+            let arg = arg
+                .map(|a| a.to_string())
+                .unwrap_or_else(|| "...".to_owned());
+            crate::Error::value_validation(
+                arg,
+                raw_value.to_string_lossy().into_owned(),
+                err.into(),
+            )
+            .with_cmd(cmd)
+        })?;
+        if !self.bounds.contains(&value) {
+            let arg = arg
+                .map(|a| a.to_string())
+                .unwrap_or_else(|| "...".to_owned());
+            return Err(crate::Error::value_validation(
+                arg,
+                raw_value.to_string_lossy().into_owned(),
+                format!("{} is not in {}", value, self.format_bounds()).into(),
+            )
+            .with_cmd(cmd));
+        }
+
+        let value: Result<Self::Value, _> = value.try_into();
+        let value = value.map_err(|err| {
+            let arg = arg
+                .map(|a| a.to_string())
+                .unwrap_or_else(|| "...".to_owned());
+            crate::Error::value_validation(
+                arg,
+                raw_value.to_string_lossy().into_owned(),
+                err.into(),
+            )
+            .with_cmd(cmd)
+        })?;
+
+        Ok(value)
+    }
+}
+
+impl<T: std::convert::TryFrom<u64>, B: RangeBounds<u64>> From<B> for RangedU64ValueParser<T> {
+    fn from(range: B) -> Self {
+        Self {
+            bounds: (range.start_bound().cloned(), range.end_bound().cloned()),
+            target: Default::default(),
+        }
+    }
+}
+
+impl<T: std::convert::TryFrom<u64>> Default for RangedU64ValueParser<T> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Implementation for [`ValueParser::bool`]
+///
+/// Useful for composing new [`TypedValueParser`]s
+#[derive(Copy, Clone, Debug)]
+#[non_exhaustive]
+pub struct BoolValueParser {}
+
+impl BoolValueParser {
+    /// Implementation for [`ValueParser::bool`]
+    pub fn new() -> Self {
+        Self {}
+    }
+
+    fn possible_values() -> impl Iterator<Item = crate::PossibleValue<'static>> {
+        ["true", "false"]
+            .iter()
+            .copied()
+            .map(crate::PossibleValue::new)
+    }
+}
+
+impl TypedValueParser for BoolValueParser {
+    type Value = bool;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        let value = if value == std::ffi::OsStr::new("true") {
+            true
+        } else if value == std::ffi::OsStr::new("false") {
+            false
+        } else {
+            // Intentionally showing hidden as we hide all of them
+            let possible_vals = Self::possible_values()
+                .map(|v| v.get_name())
+                .collect::<Vec<_>>();
+
+            return Err(crate::Error::invalid_value(
+                cmd,
+                value.to_string_lossy().into_owned(),
+                &possible_vals,
+                arg.map(ToString::to_string)
+                    .unwrap_or_else(|| "...".to_owned()),
+            ));
+        };
+        Ok(value)
+    }
+
+    fn possible_values(
+        &self,
+    ) -> Option<Box<dyn Iterator<Item = crate::PossibleValue<'static>> + '_>> {
+        Some(Box::new(Self::possible_values()))
+    }
+}
+
+impl Default for BoolValueParser {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Parse false-like string values, everything else is `true`
+///
+/// See also:
+/// - [`ValueParser::bool`] for assuming non-false is true
+/// - [`BoolishValueParser`] for different human readable bool representations
+///
+/// # Example
+///
+/// Usage:
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("append")
+///             .value_parser(clap::builder::FalseyValueParser::new())
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "true"]).unwrap();
+/// let port: bool = *m.get_one("append")
+///     .expect("required");
+/// assert_eq!(port, true);
+/// ```
+///
+/// Semantics:
+/// ```rust
+/// # use std::ffi::OsStr;
+/// # use clap::builder::TypedValueParser;
+/// # let cmd = clap::Command::new("test");
+/// # let arg = None;
+/// let value_parser = clap::builder::FalseyValueParser::new();
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("random")).unwrap(), true);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("100")).unwrap(), true);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("")).unwrap(), false);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("false")).unwrap(), false);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("No")).unwrap(), false);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("oFF")).unwrap(), false);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("0")).unwrap(), false);
+/// ```
+#[derive(Copy, Clone, Debug)]
+#[non_exhaustive]
+pub struct FalseyValueParser {}
+
+impl FalseyValueParser {
+    /// Parse false-like string values, everything else is `true`
+    pub fn new() -> Self {
+        Self {}
+    }
+
+    fn possible_values() -> impl Iterator<Item = crate::PossibleValue<'static>> {
+        crate::util::TRUE_LITERALS
+            .iter()
+            .chain(crate::util::FALSE_LITERALS.iter())
+            .copied()
+            .map(|l| crate::PossibleValue::new(l).hide(l != "true" && l != "false"))
+    }
+}
+
+impl TypedValueParser for FalseyValueParser {
+    type Value = bool;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        _arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        let value = value.to_str().ok_or_else(|| {
+            crate::Error::invalid_utf8(
+                cmd,
+                crate::output::Usage::new(cmd).create_usage_with_title(&[]),
+            )
+        })?;
+        let value = if value.is_empty() {
+            false
+        } else {
+            crate::util::str_to_bool(value).unwrap_or(true)
+        };
+        Ok(value)
+    }
+
+    fn possible_values(
+        &self,
+    ) -> Option<Box<dyn Iterator<Item = crate::PossibleValue<'static>> + '_>> {
+        Some(Box::new(Self::possible_values()))
+    }
+}
+
+impl Default for FalseyValueParser {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Parse bool-like string values, everything else is `true`
+///
+/// See also:
+/// - [`ValueParser::bool`] for different human readable bool representations
+/// - [`FalseyValueParser`] for assuming non-false is true
+///
+/// # Example
+///
+/// Usage:
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("append")
+///             .value_parser(clap::builder::BoolishValueParser::new())
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "true"]).unwrap();
+/// let port: bool = *m.get_one("append")
+///     .expect("required");
+/// assert_eq!(port, true);
+/// ```
+///
+/// Semantics:
+/// ```rust
+/// # use std::ffi::OsStr;
+/// # use clap::builder::TypedValueParser;
+/// # let cmd = clap::Command::new("test");
+/// # let arg = None;
+/// let value_parser = clap::builder::BoolishValueParser::new();
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("random")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("")).is_err());
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("100")).is_err());
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("true")).unwrap(), true);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("Yes")).unwrap(), true);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("oN")).unwrap(), true);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("1")).unwrap(), true);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("false")).unwrap(), false);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("No")).unwrap(), false);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("oFF")).unwrap(), false);
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("0")).unwrap(), false);
+/// ```
+#[derive(Copy, Clone, Debug)]
+#[non_exhaustive]
+pub struct BoolishValueParser {}
+
+impl BoolishValueParser {
+    /// Parse bool-like string values, everything else is `true`
+    pub fn new() -> Self {
+        Self {}
+    }
+
+    fn possible_values() -> impl Iterator<Item = crate::PossibleValue<'static>> {
+        crate::util::TRUE_LITERALS
+            .iter()
+            .chain(crate::util::FALSE_LITERALS.iter())
+            .copied()
+            .map(|l| crate::PossibleValue::new(l).hide(l != "true" && l != "false"))
+    }
+}
+
+impl TypedValueParser for BoolishValueParser {
+    type Value = bool;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        let value = value.to_str().ok_or_else(|| {
+            crate::Error::invalid_utf8(
+                cmd,
+                crate::output::Usage::new(cmd).create_usage_with_title(&[]),
+            )
+        })?;
+        let value = crate::util::str_to_bool(value).ok_or_else(|| {
+            let arg = arg
+                .map(|a| a.to_string())
+                .unwrap_or_else(|| "...".to_owned());
+            crate::Error::value_validation(arg, value.to_owned(), "value was not a boolean".into())
+                .with_cmd(cmd)
+        })?;
+        Ok(value)
+    }
+
+    fn possible_values(
+        &self,
+    ) -> Option<Box<dyn Iterator<Item = crate::PossibleValue<'static>> + '_>> {
+        Some(Box::new(Self::possible_values()))
+    }
+}
+
+impl Default for BoolishValueParser {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Parse non-empty string values
+///
+/// See also:
+/// - [`ValueParser::string`]
+///
+/// # Example
+///
+/// Usage:
+/// ```rust
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("append")
+///             .value_parser(clap::builder::NonEmptyStringValueParser::new())
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "true"]).unwrap();
+/// let port: &String = m.get_one("append")
+///     .expect("required");
+/// assert_eq!(port, "true");
+/// ```
+///
+/// Semantics:
+/// ```rust
+/// # use std::ffi::OsStr;
+/// # use clap::builder::TypedValueParser;
+/// # let cmd = clap::Command::new("test");
+/// # let arg = None;
+/// let value_parser = clap::builder::NonEmptyStringValueParser::new();
+/// assert_eq!(value_parser.parse_ref(&cmd, arg, OsStr::new("random")).unwrap(), "random");
+/// assert!(value_parser.parse_ref(&cmd, arg, OsStr::new("")).is_err());
+/// ```
+#[derive(Copy, Clone, Debug)]
+#[non_exhaustive]
+pub struct NonEmptyStringValueParser {}
+
+impl NonEmptyStringValueParser {
+    /// Parse non-empty string values
+    pub fn new() -> Self {
+        Self {}
+    }
+}
+
+impl TypedValueParser for NonEmptyStringValueParser {
+    type Value = String;
+
+    fn parse_ref(
+        &self,
+        cmd: &crate::Command,
+        arg: Option<&crate::Arg>,
+        value: &std::ffi::OsStr,
+    ) -> Result<Self::Value, crate::Error> {
+        if value.is_empty() {
+            return Err(crate::Error::empty_value(
+                cmd,
+                &[],
+                arg.map(ToString::to_string)
+                    .unwrap_or_else(|| "...".to_owned()),
+            ));
+        }
+        let value = value.to_str().ok_or_else(|| {
+            crate::Error::invalid_utf8(
+                cmd,
+                crate::output::Usage::new(cmd).create_usage_with_title(&[]),
+            )
+        })?;
+        Ok(value.to_owned())
+    }
+}
+
+impl Default for NonEmptyStringValueParser {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Register a type with [value_parser!][crate::value_parser!]
+///
+/// # Example
+///
+/// ```rust
+/// #[derive(Copy, Clone, Debug)]
+/// pub struct Custom(u32);
+///
+/// impl clap::builder::ValueParserFactory for Custom {
+///     type Parser = CustomValueParser;
+///     fn value_parser() -> Self::Parser {
+///         CustomValueParser
+///     }
+/// }
+///
+/// #[derive(Clone, Debug)]
+/// pub struct CustomValueParser;
+/// impl clap::builder::TypedValueParser for CustomValueParser {
+///     type Value = Custom;
+///
+///     fn parse_ref(
+///         &self,
+///         cmd: &clap::Command,
+///         arg: Option<&clap::Arg>,
+///         value: &std::ffi::OsStr,
+///     ) -> Result<Self::Value, clap::Error> {
+///         let inner = clap::value_parser!(u32);
+///         let val = inner.parse_ref(cmd, arg, value)?;
+///         Ok(Custom(val))
+///     }
+/// }
+///
+/// let parser: CustomValueParser = clap::value_parser!(Custom);
+/// ```
+pub trait ValueParserFactory {
+    /// Generated parser, usually [`ValueParser`].
+    ///
+    /// It should at least be a type that supports `Into<ValueParser>`.  A non-`ValueParser` type
+    /// allows the caller to do further initialization on the parser.
+    type Parser;
+
+    /// Create the specified [`Self::Parser`]
+    fn value_parser() -> Self::Parser;
+}
+impl ValueParserFactory for String {
+    type Parser = ValueParser;
+    fn value_parser() -> Self::Parser {
+        ValueParser::string()
+    }
+}
+impl ValueParserFactory for std::ffi::OsString {
+    type Parser = ValueParser;
+    fn value_parser() -> Self::Parser {
+        ValueParser::os_string()
+    }
+}
+impl ValueParserFactory for std::path::PathBuf {
+    type Parser = ValueParser;
+    fn value_parser() -> Self::Parser {
+        ValueParser::path_buf()
+    }
+}
+impl ValueParserFactory for bool {
+    type Parser = ValueParser;
+    fn value_parser() -> Self::Parser {
+        ValueParser::bool()
+    }
+}
+impl ValueParserFactory for u8 {
+    type Parser = RangedI64ValueParser<u8>;
+    fn value_parser() -> Self::Parser {
+        let start: i64 = u8::MIN.into();
+        let end: i64 = u8::MAX.into();
+        RangedI64ValueParser::new().range(start..=end)
+    }
+}
+impl ValueParserFactory for i8 {
+    type Parser = RangedI64ValueParser<i8>;
+    fn value_parser() -> Self::Parser {
+        let start: i64 = i8::MIN.into();
+        let end: i64 = i8::MAX.into();
+        RangedI64ValueParser::new().range(start..=end)
+    }
+}
+impl ValueParserFactory for u16 {
+    type Parser = RangedI64ValueParser<u16>;
+    fn value_parser() -> Self::Parser {
+        let start: i64 = u16::MIN.into();
+        let end: i64 = u16::MAX.into();
+        RangedI64ValueParser::new().range(start..=end)
+    }
+}
+impl ValueParserFactory for i16 {
+    type Parser = RangedI64ValueParser<i16>;
+    fn value_parser() -> Self::Parser {
+        let start: i64 = i16::MIN.into();
+        let end: i64 = i16::MAX.into();
+        RangedI64ValueParser::new().range(start..=end)
+    }
+}
+impl ValueParserFactory for u32 {
+    type Parser = RangedI64ValueParser<u32>;
+    fn value_parser() -> Self::Parser {
+        let start: i64 = u32::MIN.into();
+        let end: i64 = u32::MAX.into();
+        RangedI64ValueParser::new().range(start..=end)
+    }
+}
+impl ValueParserFactory for i32 {
+    type Parser = RangedI64ValueParser<i32>;
+    fn value_parser() -> Self::Parser {
+        let start: i64 = i32::MIN.into();
+        let end: i64 = i32::MAX.into();
+        RangedI64ValueParser::new().range(start..=end)
+    }
+}
+impl ValueParserFactory for i64 {
+    type Parser = RangedI64ValueParser<i64>;
+    fn value_parser() -> Self::Parser {
+        RangedI64ValueParser::new()
+    }
+}
+impl ValueParserFactory for u64 {
+    type Parser = RangedU64ValueParser<u64>;
+    fn value_parser() -> Self::Parser {
+        RangedU64ValueParser::new()
+    }
+}
+
+#[doc(hidden)]
+#[derive(Debug)]
+pub struct _AutoValueParser<T>(std::marker::PhantomData<T>);
+
+impl<T> _AutoValueParser<T> {
+    #[doc(hidden)]
+    #[allow(clippy::new_without_default)]
+    pub fn new() -> Self {
+        Self(Default::default())
+    }
+}
+
+/// Unstable [`ValueParser`]
+///
+/// Implementation may change to more specific instance in the future
+#[doc(hidden)]
+#[derive(Debug)]
+pub struct _AnonymousValueParser(ValueParser);
+
+#[doc(hidden)]
+pub mod via_prelude {
+    use super::*;
+
+    #[doc(hidden)]
+    pub trait _ValueParserViaFactory: private::_ValueParserViaFactorySealed {
+        type Parser;
+        fn value_parser(&self) -> Self::Parser;
+    }
+    impl<P: ValueParserFactory> _ValueParserViaFactory for &&_AutoValueParser<P> {
+        type Parser = P::Parser;
+        fn value_parser(&self) -> Self::Parser {
+            P::value_parser()
+        }
+    }
+
+    #[doc(hidden)]
+    pub trait _ValueParserViaValueEnum: private::_ValueParserViaValueEnumSealed {
+        type Output;
+
+        fn value_parser(&self) -> Self::Output;
+    }
+    impl<E: crate::ValueEnum + Clone + Send + Sync + 'static> _ValueParserViaValueEnum
+        for &_AutoValueParser<E>
+    {
+        type Output = EnumValueParser<E>;
+
+        fn value_parser(&self) -> Self::Output {
+            EnumValueParser::<E>::new()
+        }
+    }
+
+    #[doc(hidden)]
+    pub trait _ValueParserViaFromStr: private::_ValueParserViaFromStrSealed {
+        fn value_parser(&self) -> _AnonymousValueParser;
+    }
+    impl<FromStr> _ValueParserViaFromStr for _AutoValueParser<FromStr>
+    where
+        FromStr: std::str::FromStr + std::any::Any + Clone + Send + Sync + 'static,
+        <FromStr as std::str::FromStr>::Err:
+            Into<Box<dyn std::error::Error + Send + Sync + 'static>>,
+    {
+        fn value_parser(&self) -> _AnonymousValueParser {
+            let func: fn(&str) -> Result<FromStr, <FromStr as std::str::FromStr>::Err> =
+                FromStr::from_str;
+            _AnonymousValueParser(ValueParser::new(func))
+        }
+    }
+}
+
+/// Select a [`ValueParser`] implementation from the intended type
+///
+/// To register a custom type with this macro, implement [`ValueParserFactory`].
+///
+/// # Example
+///
+/// Usage:
+/// ```rust
+/// # use std::path::PathBuf;
+/// # use std::path::Path;
+/// let mut cmd = clap::Command::new("raw")
+///     .arg(
+///         clap::Arg::new("output")
+///             .value_parser(clap::value_parser!(PathBuf))
+///             .required(true)
+///     );
+///
+/// let m = cmd.try_get_matches_from_mut(["cmd", "file.txt"]).unwrap();
+/// let port: &PathBuf = m.get_one("output")
+///     .expect("required");
+/// assert_eq!(port, Path::new("file.txt"));
+/// ```
+///
+/// Supported types:
+/// ```rust
+/// // Built-in types
+/// let parser = clap::value_parser!(String);
+/// assert_eq!(format!("{:?}", parser), "ValueParser::string");
+/// let parser = clap::value_parser!(std::ffi::OsString);
+/// assert_eq!(format!("{:?}", parser), "ValueParser::os_string");
+/// let parser = clap::value_parser!(std::path::PathBuf);
+/// assert_eq!(format!("{:?}", parser), "ValueParser::path_buf");
+/// let parser = clap::value_parser!(u16).range(3000..);
+/// assert_eq!(format!("{:?}", parser), "RangedI64ValueParser { bounds: (Included(3000), Included(65535)), target: PhantomData }");
+/// let parser = clap::value_parser!(u64).range(3000..);
+/// assert_eq!(format!("{:?}", parser), "RangedU64ValueParser { bounds: (Included(3000), Unbounded), target: PhantomData }");
+///
+/// // FromStr types
+/// let parser = clap::value_parser!(usize);
+/// assert_eq!(format!("{:?}", parser), "_AnonymousValueParser(ValueParser::other(usize))");
+///
+/// // ValueEnum types
+/// #[derive(Copy, Clone, Debug, PartialEq, Eq)]
+/// enum ColorChoice {
+///     Always,
+///     Auto,
+///     Never,
+/// }
+/// impl clap::ValueEnum for ColorChoice {
+///     // ...
+/// #     fn value_variants<'a>() -> &'a [Self] {
+/// #         &[Self::Always, Self::Auto, Self::Never]
+/// #     }
+/// #     fn to_possible_value<'a>(&self) -> Option<clap::PossibleValue<'a>> {
+/// #         match self {
+/// #             Self::Always => Some(clap::PossibleValue::new("always")),
+/// #             Self::Auto => Some(clap::PossibleValue::new("auto")),
+/// #             Self::Never => Some(clap::PossibleValue::new("never")),
+/// #         }
+/// #     }
+/// }
+/// let parser = clap::value_parser!(ColorChoice);
+/// assert_eq!(format!("{:?}", parser), "EnumValueParser(PhantomData)");
+/// ```
+#[macro_export]
+macro_rules! value_parser {
+    ($name:ty) => {{
+        use $crate::builder::via_prelude::*;
+        let auto = $crate::builder::_AutoValueParser::<$name>::new();
+        (&&&auto).value_parser()
+    }};
+}
+
+mod private {
+    use super::*;
+
+    pub trait _ValueParserViaSelfSealed {}
+    impl<P: Into<ValueParser>> _ValueParserViaSelfSealed for &&&_AutoValueParser<P> {}
+
+    pub trait _ValueParserViaFactorySealed {}
+    impl<P: ValueParserFactory> _ValueParserViaFactorySealed for &&_AutoValueParser<P> {}
+
+    pub trait _ValueParserViaValueEnumSealed {}
+    impl<E: crate::ValueEnum> _ValueParserViaValueEnumSealed for &_AutoValueParser<E> {}
+
+    pub trait _ValueParserViaFromStrSealed {}
+    impl<FromStr> _ValueParserViaFromStrSealed for _AutoValueParser<FromStr>
+    where
+        FromStr: std::str::FromStr + std::any::Any + Send + Sync + 'static,
+        <FromStr as std::str::FromStr>::Err:
+            Into<Box<dyn std::error::Error + Send + Sync + 'static>>,
+    {
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn ensure_typed_applies_to_parse() {
+        fn parse(_: &str) -> Result<usize, std::io::Error> {
+            Ok(10)
+        }
+        let cmd = crate::Command::new("cmd");
+        let arg = None;
+        assert_eq!(
+            TypedValueParser::parse_ref(&parse, &cmd, arg, std::ffi::OsStr::new("foo")).unwrap(),
+            10
+        );
+    }
+}
diff --git a/vendor/clap-3.2.20/src/derive.rs b/vendor/clap-3.2.20/src/derive.rs
new file mode 100644
index 000000000..b6ac04df6
--- /dev/null
+++ b/vendor/clap-3.2.20/src/derive.rs
@@ -0,0 +1,577 @@
+//! This module contains traits that are usable with the `#[derive(...)].`
+//! macros in [`clap_derive`].
+
+use crate::{ArgMatches, Command, Error, PossibleValue};
+
+use std::ffi::OsString;
+
+/// Parse command-line arguments into `Self`.
+///
+/// The primary one-stop-shop trait used to create an instance of a `clap`
+/// [`Command`], conduct the parsing, and turn the resulting [`ArgMatches`] back
+/// into concrete instance of the user struct.
+///
+/// This trait is primarily a convenience on top of [`FromArgMatches`] +
+/// [`CommandFactory`] which uses those two underlying traits to build the two
+/// fundamental functions `parse` which uses the `std::env::args_os` iterator,
+/// and `parse_from` which allows the consumer to supply the iterator (along
+/// with fallible options for each).
+///
+/// See also [`Subcommand`] and [`Args`].
+///
+/// See the [derive reference](crate::_derive) for attributes and best practices.
+///
+/// **NOTE:** Deriving requires the [`derive` feature flag][crate::_features]
+///
+/// # Examples
+///
+/// The following example creates a `Context` struct that would be used
+/// throughout the application representing the normalized values coming from
+/// the CLI.
+///
+#[cfg_attr(not(feature = "derive"), doc = " ```ignore")]
+#[cfg_attr(feature = "derive", doc = " ```")]
+/// /// My super CLI
+/// #[derive(clap::Parser)]
+/// #[clap(name = "demo")]
+/// struct Context {
+///     /// More verbose output
+///     #[clap(long)]
+///     verbose: bool,
+///     /// An optional name
+///     #[clap(short, long)]
+///     name: Option<String>,
+/// }
+/// ```
+///
+/// The equivalent [`Command`] struct + `From` implementation:
+///
+/// ```rust
+/// # use clap::{Command, Arg, ArgMatches, ArgAction};
+/// Command::new("demo")
+///     .about("My super CLI")
+///     .arg(Arg::new("verbose")
+///         .long("verbose")
+///         .action(ArgAction::SetTrue)
+///         .help("More verbose output"))
+///     .arg(Arg::new("name")
+///         .long("name")
+///         .short('n')
+///         .help("An optional name")
+///         .takes_value(true));
+///
+/// struct Context {
+///     verbose: bool,
+///     name: Option<String>,
+/// }
+///
+/// impl From<ArgMatches> for Context {
+///     fn from(m: ArgMatches) -> Self {
+///         Context {
+///             verbose: *m.get_one::<bool>("verbose").expect("defaulted_by_clap"),
+///             name: m.get_one::<String>("name").cloned(),
+///         }
+///     }
+/// }
+/// ```
+///
+pub trait Parser: FromArgMatches + CommandFactory + Sized {
+    /// Parse from `std::env::args_os()`, exit on error
+    fn parse() -> Self {
+        let mut matches = <Self as CommandFactory>::command().get_matches();
+        let res = <Self as FromArgMatches>::from_arg_matches_mut(&mut matches)
+            .map_err(format_error::<Self>);
+        match res {
+            Ok(s) => s,
+            Err(e) => {
+                // Since this is more of a development-time error, we aren't doing as fancy of a quit
+                // as `get_matches`
+                e.exit()
+            }
+        }
+    }
+
+    /// Parse from `std::env::args_os()`, return Err on error.
+    fn try_parse() -> Result<Self, Error> {
+        let mut matches = <Self as CommandFactory>::command().try_get_matches()?;
+        <Self as FromArgMatches>::from_arg_matches_mut(&mut matches).map_err(format_error::<Self>)
+    }
+
+    /// Parse from iterator, exit on error
+    fn parse_from<I, T>(itr: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        let mut matches = <Self as CommandFactory>::command().get_matches_from(itr);
+        let res = <Self as FromArgMatches>::from_arg_matches_mut(&mut matches)
+            .map_err(format_error::<Self>);
+        match res {
+            Ok(s) => s,
+            Err(e) => {
+                // Since this is more of a development-time error, we aren't doing as fancy of a quit
+                // as `get_matches_from`
+                e.exit()
+            }
+        }
+    }
+
+    /// Parse from iterator, return Err on error.
+    fn try_parse_from<I, T>(itr: I) -> Result<Self, Error>
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        let mut matches = <Self as CommandFactory>::command().try_get_matches_from(itr)?;
+        <Self as FromArgMatches>::from_arg_matches_mut(&mut matches).map_err(format_error::<Self>)
+    }
+
+    /// Update from iterator, exit on error
+    fn update_from<I, T>(&mut self, itr: I)
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        let mut matches = <Self as CommandFactory>::command_for_update().get_matches_from(itr);
+        let res = <Self as FromArgMatches>::update_from_arg_matches_mut(self, &mut matches)
+            .map_err(format_error::<Self>);
+        if let Err(e) = res {
+            // Since this is more of a development-time error, we aren't doing as fancy of a quit
+            // as `get_matches_from`
+            e.exit()
+        }
+    }
+
+    /// Update from iterator, return Err on error.
+    fn try_update_from<I, T>(&mut self, itr: I) -> Result<(), Error>
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        let mut matches =
+            <Self as CommandFactory>::command_for_update().try_get_matches_from(itr)?;
+        <Self as FromArgMatches>::update_from_arg_matches_mut(self, &mut matches)
+            .map_err(format_error::<Self>)
+    }
+
+    /// Deprecated, `StructOpt::clap` replaced with [`CommandFactory::command`] (derive as part of
+    /// [`Parser`])
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "`StructOpt::clap` is replaced with `CommandFactory::command` (derived as part of `Parser`)"
+        )
+    )]
+    #[doc(hidden)]
+    fn clap<'help>() -> Command<'help> {
+        <Self as CommandFactory>::command()
+    }
+
+    /// Deprecated, `StructOpt::from_clap` replaced with [`FromArgMatches::from_arg_matches_mut`] (derive as part of
+    /// [`Parser`])
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "`StructOpt::from_clap` is replaced with `FromArgMatches::from_arg_matches_mut` (derived as part of `Parser`)"
+        )
+    )]
+    #[doc(hidden)]
+    fn from_clap(matches: &ArgMatches) -> Self {
+        <Self as FromArgMatches>::from_arg_matches(matches).unwrap()
+    }
+
+    /// Deprecated, `StructOpt::from_args` replaced with `Parser::parse` (note the change in derives)
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "`StructOpt::from_args` is replaced with `Parser::parse` (note the change in derives)"
+        )
+    )]
+    #[doc(hidden)]
+    fn from_args() -> Self {
+        Self::parse()
+    }
+
+    /// Deprecated, `StructOpt::from_args_safe` replaced with `Parser::try_parse` (note the change in derives)
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "`StructOpt::from_args_safe` is replaced with `Parser::try_parse` (note the change in derives)"
+        )
+    )]
+    #[doc(hidden)]
+    fn from_args_safe() -> Result<Self, Error> {
+        Self::try_parse()
+    }
+
+    /// Deprecated, `StructOpt::from_iter` replaced with `Parser::parse_from` (note the change in derives)
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "`StructOpt::from_iter` is replaced with `Parser::parse_from` (note the change in derives)"
+        )
+    )]
+    #[doc(hidden)]
+    fn from_iter<I, T>(itr: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        Self::parse_from(itr)
+    }
+
+    /// Deprecated, `StructOpt::from_iter_safe` replaced with `Parser::try_parse_from` (note the
+    /// change in derives)
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "`StructOpt::from_iter_safe` is replaced with `Parser::try_parse_from` (note the change in derives)"
+        )
+    )]
+    #[doc(hidden)]
+    fn from_iter_safe<I, T>(itr: I) -> Result<Self, Error>
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<OsString> + Clone,
+    {
+        Self::try_parse_from(itr)
+    }
+}
+
+/// Create a [`Command`] relevant for a user-defined container.
+///
+/// Derived as part of [`Parser`].
+pub trait CommandFactory: Sized {
+    /// Build a [`Command`] that can instantiate `Self`.
+    ///
+    /// See [`FromArgMatches::from_arg_matches_mut`] for instantiating `Self`.
+    fn command<'help>() -> Command<'help> {
+        #[allow(deprecated)]
+        Self::into_app()
+    }
+    /// Deprecated, replaced with `CommandFactory::command`
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `CommandFactory::command")
+    )]
+    fn into_app<'help>() -> Command<'help>;
+    /// Build a [`Command`] that can update `self`.
+    ///
+    /// See [`FromArgMatches::update_from_arg_matches_mut`] for updating `self`.
+    fn command_for_update<'help>() -> Command<'help> {
+        #[allow(deprecated)]
+        Self::into_app_for_update()
+    }
+    /// Deprecated, replaced with `CommandFactory::command_for_update`
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.1.0",
+            note = "Replaced with `CommandFactory::command_for_update"
+        )
+    )]
+    fn into_app_for_update<'help>() -> Command<'help>;
+}
+
+/// Converts an instance of [`ArgMatches`] to a user-defined container.
+///
+/// Derived as part of [`Parser`], [`Args`], and [`Subcommand`].
+pub trait FromArgMatches: Sized {
+    /// Instantiate `Self` from [`ArgMatches`], parsing the arguments as needed.
+    ///
+    /// Motivation: If our application had two CLI options, `--name
+    /// <STRING>` and the flag `--debug`, we may create a struct as follows:
+    ///
+    #[cfg_attr(not(feature = "derive"), doc = " ```ignore")]
+    #[cfg_attr(feature = "derive", doc = " ```no_run")]
+    /// struct Context {
+    ///     name: String,
+    ///     debug: bool
+    /// }
+    /// ```
+    ///
+    /// We then need to convert the `ArgMatches` that `clap` generated into our struct.
+    /// `from_arg_matches` serves as the equivalent of:
+    ///
+    #[cfg_attr(not(feature = "derive"), doc = " ```ignore")]
+    #[cfg_attr(feature = "derive", doc = " ```no_run")]
+    /// # use clap::ArgMatches;
+    /// # struct Context {
+    /// #   name: String,
+    /// #   debug: bool
+    /// # }
+    /// impl From<ArgMatches> for Context {
+    ///    fn from(m: ArgMatches) -> Self {
+    ///        Context {
+    ///            name: m.get_one::<String>("name").unwrap().clone(),
+    ///            debug: *m.get_one::<bool>("debug").expect("defaulted by clap"),
+    ///        }
+    ///    }
+    /// }
+    /// ```
+    fn from_arg_matches(matches: &ArgMatches) -> Result<Self, Error>;
+
+    /// Instantiate `Self` from [`ArgMatches`], parsing the arguments as needed.
+    ///
+    /// Motivation: If our application had two CLI options, `--name
+    /// <STRING>` and the flag `--debug`, we may create a struct as follows:
+    ///
+    #[cfg_attr(not(feature = "derive"), doc = " ```ignore")]
+    #[cfg_attr(feature = "derive", doc = " ```no_run")]
+    /// struct Context {
+    ///     name: String,
+    ///     debug: bool
+    /// }
+    /// ```
+    ///
+    /// We then need to convert the `ArgMatches` that `clap` generated into our struct.
+    /// `from_arg_matches_mut` serves as the equivalent of:
+    ///
+    #[cfg_attr(not(feature = "derive"), doc = " ```ignore")]
+    #[cfg_attr(feature = "derive", doc = " ```no_run")]
+    /// # use clap::ArgMatches;
+    /// # struct Context {
+    /// #   name: String,
+    /// #   debug: bool
+    /// # }
+    /// impl From<ArgMatches> for Context {
+    ///    fn from(m: ArgMatches) -> Self {
+    ///        Context {
+    ///            name: m.get_one::<String>("name").unwrap().to_string(),
+    ///            debug: *m.get_one::<bool>("debug").expect("defaulted by clap"),
+    ///        }
+    ///    }
+    /// }
+    /// ```
+    fn from_arg_matches_mut(matches: &mut ArgMatches) -> Result<Self, Error> {
+        Self::from_arg_matches(matches)
+    }
+
+    /// Assign values from `ArgMatches` to `self`.
+    fn update_from_arg_matches(&mut self, matches: &ArgMatches) -> Result<(), Error>;
+
+    /// Assign values from `ArgMatches` to `self`.
+    fn update_from_arg_matches_mut(&mut self, matches: &mut ArgMatches) -> Result<(), Error> {
+        self.update_from_arg_matches(matches)
+    }
+}
+
+/// Parse a set of arguments into a user-defined container.
+///
+/// Implementing this trait lets a parent container delegate argument parsing behavior to `Self`.
+/// with:
+/// - `#[clap(flatten)] args: ChildArgs`: Attribute can only be used with struct fields that impl
+///   `Args`.
+/// - `Variant(ChildArgs)`: No attribute is used with enum variants that impl `Args`.
+///
+/// See the [derive reference](crate::_derive) for attributes and best practices.
+///
+/// **NOTE:** Deriving requires the [`derive` feature flag][crate::_features]
+///
+/// # Example
+///
+#[cfg_attr(not(feature = "derive"), doc = " ```ignore")]
+#[cfg_attr(feature = "derive", doc = " ```")]
+/// #[derive(clap::Parser)]
+/// struct Args {
+///     #[clap(flatten)]
+///     logging: LogArgs,
+/// }
+///
+/// #[derive(clap::Args)]
+/// struct LogArgs {
+///     #[clap(long, short = 'v', parse(from_occurrences))]
+///     verbose: i8,
+/// }
+/// ```
+pub trait Args: FromArgMatches + Sized {
+    /// Append to [`Command`] so it can instantiate `Self`.
+    ///
+    /// See also [`CommandFactory`].
+    fn augment_args(cmd: Command<'_>) -> Command<'_>;
+    /// Append to [`Command`] so it can update `self`.
+    ///
+    /// This is used to implement `#[clap(flatten)]`
+    ///
+    /// See also [`CommandFactory`].
+    fn augment_args_for_update(cmd: Command<'_>) -> Command<'_>;
+}
+
+/// Parse a sub-command into a user-defined enum.
+///
+/// Implementing this trait lets a parent container delegate subcommand behavior to `Self`.
+/// with:
+/// - `#[clap(subcommand)] field: SubCmd`: Attribute can be used with either struct fields or enum
+///   variants that impl `Subcommand`.
+/// - `#[clap(flatten)] Variant(SubCmd)`: Attribute can only be used with enum variants that impl
+///   `Subcommand`.
+///
+/// See the [derive reference](crate::_derive) for attributes and best practices.
+///
+/// **NOTE:** Deriving requires the [`derive` feature flag][crate::_features]
+///
+/// # Example
+///
+#[cfg_attr(not(feature = "derive"), doc = " ```ignore")]
+#[cfg_attr(feature = "derive", doc = " ```")]
+/// #[derive(clap::Parser)]
+/// struct Args {
+///     #[clap(subcommand)]
+///     action: Action,
+/// }
+///
+/// #[derive(clap::Subcommand)]
+/// enum Action {
+///     Add,
+///     Remove,
+/// }
+/// ```
+pub trait Subcommand: FromArgMatches + Sized {
+    /// Append to [`Command`] so it can instantiate `Self`.
+    ///
+    /// See also [`CommandFactory`].
+    fn augment_subcommands(cmd: Command<'_>) -> Command<'_>;
+    /// Append to [`Command`] so it can update `self`.
+    ///
+    /// This is used to implement `#[clap(flatten)]`
+    ///
+    /// See also [`CommandFactory`].
+    fn augment_subcommands_for_update(cmd: Command<'_>) -> Command<'_>;
+    /// Test whether `Self` can parse a specific subcommand
+    fn has_subcommand(name: &str) -> bool;
+}
+
+/// Parse arguments into enums.
+///
+/// When deriving [`Parser`], a field whose type implements `ValueEnum` can have the attribute
+/// `#[clap(value_enum)]` which will
+/// - Call [`Arg::possible_values`][crate::Arg::possible_values]
+/// - Allowing using the `#[clap(default_value_t)]` attribute without implementing `Display`.
+///
+/// See the [derive reference](crate::_derive) for attributes and best practices.
+///
+/// **NOTE:** Deriving requires the [`derive` feature flag][crate::_features]
+///
+/// # Example
+///
+#[cfg_attr(not(feature = "derive"), doc = " ```ignore")]
+#[cfg_attr(feature = "derive", doc = " ```")]
+/// #[derive(clap::Parser)]
+/// struct Args {
+///     #[clap(value_enum)]
+///     level: Level,
+/// }
+///
+/// #[derive(clap::ValueEnum, Clone)]
+/// enum Level {
+///     Debug,
+///     Info,
+///     Warning,
+///     Error,
+/// }
+/// ```
+pub trait ValueEnum: Sized + Clone {
+    /// All possible argument values, in display order.
+    fn value_variants<'a>() -> &'a [Self];
+
+    /// Parse an argument into `Self`.
+    fn from_str(input: &str, ignore_case: bool) -> Result<Self, String> {
+        Self::value_variants()
+            .iter()
+            .find(|v| {
+                v.to_possible_value()
+                    .expect("ValueEnum::value_variants contains only values with a corresponding ValueEnum::to_possible_value")
+                    .matches(input, ignore_case)
+            })
+            .cloned()
+            .ok_or_else(|| format!("Invalid variant: {}", input))
+    }
+
+    /// The canonical argument value.
+    ///
+    /// The value is `None` for skipped variants.
+    fn to_possible_value<'a>(&self) -> Option<PossibleValue<'a>>;
+}
+
+impl<T: Parser> Parser for Box<T> {
+    fn parse() -> Self {
+        Box::new(<T as Parser>::parse())
+    }
+
+    fn try_parse() -> Result<Self, Error> {
+        <T as Parser>::try_parse().map(Box::new)
+    }
+
+    fn parse_from<I, It>(itr: I) -> Self
+    where
+        I: IntoIterator<Item = It>,
+        It: Into<OsString> + Clone,
+    {
+        Box::new(<T as Parser>::parse_from(itr))
+    }
+
+    fn try_parse_from<I, It>(itr: I) -> Result<Self, Error>
+    where
+        I: IntoIterator<Item = It>,
+        It: Into<OsString> + Clone,
+    {
+        <T as Parser>::try_parse_from(itr).map(Box::new)
+    }
+}
+
+#[allow(deprecated)]
+impl<T: CommandFactory> CommandFactory for Box<T> {
+    fn into_app<'help>() -> Command<'help> {
+        <T as CommandFactory>::into_app()
+    }
+    fn into_app_for_update<'help>() -> Command<'help> {
+        <T as CommandFactory>::into_app_for_update()
+    }
+}
+
+impl<T: FromArgMatches> FromArgMatches for Box<T> {
+    fn from_arg_matches(matches: &ArgMatches) -> Result<Self, Error> {
+        <T as FromArgMatches>::from_arg_matches(matches).map(Box::new)
+    }
+    fn from_arg_matches_mut(matches: &mut ArgMatches) -> Result<Self, Error> {
+        <T as FromArgMatches>::from_arg_matches_mut(matches).map(Box::new)
+    }
+    fn update_from_arg_matches(&mut self, matches: &ArgMatches) -> Result<(), Error> {
+        <T as FromArgMatches>::update_from_arg_matches(self, matches)
+    }
+    fn update_from_arg_matches_mut(&mut self, matches: &mut ArgMatches) -> Result<(), Error> {
+        <T as FromArgMatches>::update_from_arg_matches_mut(self, matches)
+    }
+}
+
+impl<T: Args> Args for Box<T> {
+    fn augment_args(cmd: Command<'_>) -> Command<'_> {
+        <T as Args>::augment_args(cmd)
+    }
+    fn augment_args_for_update(cmd: Command<'_>) -> Command<'_> {
+        <T as Args>::augment_args_for_update(cmd)
+    }
+}
+
+impl<T: Subcommand> Subcommand for Box<T> {
+    fn augment_subcommands(cmd: Command<'_>) -> Command<'_> {
+        <T as Subcommand>::augment_subcommands(cmd)
+    }
+    fn augment_subcommands_for_update(cmd: Command<'_>) -> Command<'_> {
+        <T as Subcommand>::augment_subcommands_for_update(cmd)
+    }
+    fn has_subcommand(name: &str) -> bool {
+        <T as Subcommand>::has_subcommand(name)
+    }
+}
+
+fn format_error<I: CommandFactory>(err: crate::Error) -> crate::Error {
+    let mut cmd = I::command();
+    err.format(&mut cmd)
+}
diff --git a/vendor/clap-3.2.20/src/error/context.rs b/vendor/clap-3.2.20/src/error/context.rs
new file mode 100644
index 000000000..985cd4d70
--- /dev/null
+++ b/vendor/clap-3.2.20/src/error/context.rs
@@ -0,0 +1,55 @@
+/// Semantics for a piece of error information
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[non_exhaustive]
+pub enum ContextKind {
+    /// The cause of the error
+    InvalidSubcommand,
+    /// The cause of the error
+    InvalidArg,
+    /// Existing arguments
+    PriorArg,
+    /// Accepted values
+    ValidValue,
+    /// Rejected values
+    InvalidValue,
+    /// Number of values present
+    ActualNumValues,
+    /// Number of allowed values
+    ExpectedNumValues,
+    /// Minimum number of allowed values
+    MinValues,
+    /// Number of occurrences present
+    ActualNumOccurrences,
+    /// Maximum number of allowed occurrences
+    MaxOccurrences,
+    /// Potential fix for the user
+    SuggestedCommand,
+    /// Potential fix for the user
+    SuggestedSubcommand,
+    /// Potential fix for the user
+    SuggestedArg,
+    /// Potential fix for the user
+    SuggestedValue,
+    /// Trailing argument
+    TrailingArg,
+    /// A usage string
+    Usage,
+    /// An opaque message to the user
+    Custom,
+}
+
+/// A piece of error information
+#[derive(Clone, Debug, PartialEq, Eq)]
+#[non_exhaustive]
+pub enum ContextValue {
+    /// [`ContextKind`] is self-sufficient, no additional information needed
+    None,
+    /// A single value
+    Bool(bool),
+    /// A single value
+    String(String),
+    /// Many values
+    Strings(Vec<String>),
+    /// A single value
+    Number(isize),
+}
diff --git a/vendor/clap-3.2.20/src/error/kind.rs b/vendor/clap-3.2.20/src/error/kind.rs
new file mode 100644
index 000000000..4c3dc48b0
--- /dev/null
+++ b/vendor/clap-3.2.20/src/error/kind.rs
@@ -0,0 +1,440 @@
+/// Command line argument parser kind of error
+#[derive(Debug, Copy, Clone, PartialEq)]
+#[non_exhaustive]
+pub enum ErrorKind {
+    /// Occurs when an [`Arg`][crate::Arg] has a set of possible values,
+    /// and the user provides a value which isn't in that set.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("speed")
+    ///         .value_parser(["fast", "slow"]))
+    ///     .try_get_matches_from(vec!["prog", "other"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::InvalidValue);
+    /// ```
+    InvalidValue,
+
+    /// Occurs when a user provides a flag, option, argument or subcommand which isn't defined.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .arg(arg!(--flag "some flag"))
+    ///     .try_get_matches_from(vec!["prog", "--other"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::UnknownArgument);
+    /// ```
+    UnknownArgument,
+
+    /// Occurs when the user provides an unrecognized [`Subcommand`] which meets the threshold for
+    /// being similar enough to an existing subcommand.
+    /// If it doesn't meet the threshold, or the 'suggestions' feature is disabled,
+    /// the more general [`UnknownArgument`] error is returned.
+    ///
+    /// # Examples
+    ///
+    #[cfg_attr(not(feature = "suggestions"), doc = " ```no_run")]
+    #[cfg_attr(feature = "suggestions", doc = " ```")]
+    /// # use clap::{Command, Arg, ErrorKind, };
+    /// let result = Command::new("prog")
+    ///     .subcommand(Command::new("config")
+    ///         .about("Used for configuration")
+    ///         .arg(Arg::new("config_file")
+    ///             .help("The configuration file to use")))
+    ///     .try_get_matches_from(vec!["prog", "confi"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::InvalidSubcommand);
+    /// ```
+    ///
+    /// [`Subcommand`]: crate::Subcommand
+    /// [`UnknownArgument`]: ErrorKind::UnknownArgument
+    InvalidSubcommand,
+
+    /// Occurs when the user provides an unrecognized [`Subcommand`] which either
+    /// doesn't meet the threshold for being similar enough to an existing subcommand,
+    /// or the 'suggestions' feature is disabled.
+    /// Otherwise the more detailed [`InvalidSubcommand`] error is returned.
+    ///
+    /// This error typically happens when passing additional subcommand names to the `help`
+    /// subcommand. Otherwise, the more general [`UnknownArgument`] error is used.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind, };
+    /// let result = Command::new("prog")
+    ///     .subcommand(Command::new("config")
+    ///         .about("Used for configuration")
+    ///         .arg(Arg::new("config_file")
+    ///             .help("The configuration file to use")))
+    ///     .try_get_matches_from(vec!["prog", "help", "nothing"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::UnrecognizedSubcommand);
+    /// ```
+    ///
+    /// [`Subcommand`]: crate::Subcommand
+    /// [`InvalidSubcommand`]: ErrorKind::InvalidSubcommand
+    /// [`UnknownArgument`]: ErrorKind::UnknownArgument
+    UnrecognizedSubcommand,
+
+    /// Occurs when the user provides an empty value for an option that does not allow empty
+    /// values.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("color")
+    ///          .takes_value(true)
+    ///          .forbid_empty_values(true)
+    ///          .long("color"))
+    ///     .try_get_matches_from(vec!["prog", "--color="]);
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::EmptyValue);
+    /// ```
+    EmptyValue,
+
+    /// Occurs when the user doesn't use equals for an option that requires equal
+    /// sign to provide values.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let res = Command::new("prog")
+    ///     .arg(Arg::new("color")
+    ///          .takes_value(true)
+    ///          .require_equals(true)
+    ///          .long("color"))
+    ///     .try_get_matches_from(vec!["prog", "--color", "red"]);
+    /// assert!(res.is_err());
+    /// assert_eq!(res.unwrap_err().kind(), ErrorKind::NoEquals);
+    /// ```
+    NoEquals,
+
+    /// Occurs when the user provides a value for an argument with a custom validation and the
+    /// value fails that validation.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// fn is_numeric(val: &str) -> Result<(), String> {
+    ///     match val.parse::<i64>() {
+    ///         Ok(..) => Ok(()),
+    ///         Err(..) => Err(String::from("Value wasn't a number!")),
+    ///     }
+    /// }
+    ///
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("num")
+    ///          .validator(is_numeric))
+    ///     .try_get_matches_from(vec!["prog", "NotANumber"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::ValueValidation);
+    /// ```
+    ValueValidation,
+
+    /// Occurs when a user provides more values for an argument than were defined by setting
+    /// [`Arg::max_values`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("arg")
+    ///         .max_values(2))
+    ///     .try_get_matches_from(vec!["prog", "too", "many", "values"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::TooManyValues);
+    /// ```
+    /// [`Arg::max_values`]: crate::Arg::max_values()
+    TooManyValues,
+
+    /// Occurs when the user provides fewer values for an argument than were defined by setting
+    /// [`Arg::min_values`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("some_opt")
+    ///         .long("opt")
+    ///         .min_values(3))
+    ///     .try_get_matches_from(vec!["prog", "--opt", "too", "few"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::TooFewValues);
+    /// ```
+    /// [`Arg::min_values`]: crate::Arg::min_values()
+    TooFewValues,
+
+    /// Occurs when a user provides more occurrences for an argument than were defined by setting
+    /// [`Arg::max_occurrences`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("verbosity")
+    ///         .short('v')
+    ///         .max_occurrences(2))
+    ///     .try_get_matches_from(vec!["prog", "-vvv"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::TooManyOccurrences);
+    /// ```
+    /// [`Arg::max_occurrences`]: crate::Arg::max_occurrences()
+    TooManyOccurrences,
+
+    /// Occurs when the user provides a different number of values for an argument than what's
+    /// been defined by setting [`Arg::number_of_values`] or than was implicitly set by
+    /// [`Arg::value_names`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("some_opt")
+    ///         .long("opt")
+    ///         .takes_value(true)
+    ///         .number_of_values(2))
+    ///     .try_get_matches_from(vec!["prog", "--opt", "wrong"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::WrongNumberOfValues);
+    /// ```
+    ///
+    /// [`Arg::number_of_values`]: crate::Arg::number_of_values()
+    /// [`Arg::value_names`]: crate::Arg::value_names()
+    WrongNumberOfValues,
+
+    /// Occurs when the user provides two values which conflict with each other and can't be used
+    /// together.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("debug")
+    ///         .long("debug")
+    ///         .conflicts_with("color"))
+    ///     .arg(Arg::new("color")
+    ///         .long("color"))
+    ///     .try_get_matches_from(vec!["prog", "--debug", "--color"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::ArgumentConflict);
+    /// ```
+    ArgumentConflict,
+
+    /// Occurs when the user does not provide one or more required arguments.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("debug")
+    ///         .required(true))
+    ///     .try_get_matches_from(vec!["prog"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
+    /// ```
+    MissingRequiredArgument,
+
+    /// Occurs when a subcommand is required (as defined by [`Command::subcommand_required`]),
+    /// but the user does not provide one.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, ErrorKind};
+    /// let err = Command::new("prog")
+    ///     .subcommand_required(true)
+    ///     .subcommand(Command::new("test"))
+    ///     .try_get_matches_from(vec![
+    ///         "myprog",
+    ///     ]);
+    /// assert!(err.is_err());
+    /// assert_eq!(err.unwrap_err().kind(), ErrorKind::MissingSubcommand);
+    /// # ;
+    /// ```
+    ///
+    /// [`Command::subcommand_required`]: crate::Command::subcommand_required
+    MissingSubcommand,
+
+    /// Occurs when the user provides multiple values to an argument which doesn't allow that.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("debug")
+    ///         .long("debug")
+    ///         .multiple_occurrences(false))
+    ///     .try_get_matches_from(vec!["prog", "--debug", "--debug"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::UnexpectedMultipleUsage);
+    /// ```
+    UnexpectedMultipleUsage,
+
+    /// Occurs when the user provides a value containing invalid UTF-8.
+    ///
+    /// To allow arbitrary data
+    /// - Set [`Arg::allow_invalid_utf8`] for argument values
+    /// - Set [`Command::allow_invalid_utf8_for_external_subcommands`] for external-subcommand
+    ///   values
+    ///
+    /// # Platform Specific
+    ///
+    /// Non-Windows platforms only (such as Linux, Unix, OSX, etc.)
+    ///
+    /// # Examples
+    ///
+    #[cfg_attr(not(unix), doc = " ```ignore")]
+    #[cfg_attr(unix, doc = " ```")]
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// # use std::os::unix::ffi::OsStringExt;
+    /// # use std::ffi::OsString;
+    /// let result = Command::new("prog")
+    ///     .arg(Arg::new("utf8")
+    ///         .short('u')
+    ///         .takes_value(true))
+    ///     .try_get_matches_from(vec![OsString::from("myprog"),
+    ///                                 OsString::from("-u"),
+    ///                                 OsString::from_vec(vec![0xE9])]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::InvalidUtf8);
+    /// ```
+    ///
+    /// [`Arg::allow_invalid_utf8`]: crate::Arg::allow_invalid_utf8
+    /// [`Command::allow_invalid_utf8_for_external_subcommands`]: crate::Command::allow_invalid_utf8_for_external_subcommands
+    InvalidUtf8,
+
+    /// Not a true "error" as it means `--help` or similar was used.
+    /// The help message will be sent to `stdout`.
+    ///
+    /// **Note**: If the help is displayed due to an error (such as missing subcommands) it will
+    /// be sent to `stderr` instead of `stdout`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .try_get_matches_from(vec!["prog", "--help"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::DisplayHelp);
+    /// ```
+    DisplayHelp,
+
+    /// Occurs when either an argument or a [`Subcommand`] is required, as defined by
+    /// [`Command::arg_required_else_help`] , but the user did not provide
+    /// one.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind, };
+    /// let result = Command::new("prog")
+    ///     .arg_required_else_help(true)
+    ///     .subcommand(Command::new("config")
+    ///         .about("Used for configuration")
+    ///         .arg(Arg::new("config_file")
+    ///             .help("The configuration file to use")))
+    ///     .try_get_matches_from(vec!["prog"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::DisplayHelpOnMissingArgumentOrSubcommand);
+    /// ```
+    ///
+    /// [`Subcommand`]: crate::Subcommand
+    /// [`Command::arg_required_else_help`]: crate::Command::arg_required_else_help
+    DisplayHelpOnMissingArgumentOrSubcommand,
+
+    /// Not a true "error" as it means `--version` or similar was used.
+    /// The message will be sent to `stdout`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ErrorKind};
+    /// let result = Command::new("prog")
+    ///     .version("3.0")
+    ///     .try_get_matches_from(vec!["prog", "--version"]);
+    /// assert!(result.is_err());
+    /// assert_eq!(result.unwrap_err().kind(), ErrorKind::DisplayVersion);
+    /// ```
+    DisplayVersion,
+
+    /// Occurs when using the [`ArgMatches::value_of_t`] and friends to convert an argument value
+    /// into type `T`, but the argument you requested wasn't used. I.e. you asked for an argument
+    /// with name `config` to be converted, but `config` wasn't used by the user.
+    ///
+    /// [`ArgMatches::value_of_t`]: crate::ArgMatches::value_of_t()
+    ArgumentNotFound,
+
+    /// Represents an [I/O error].
+    /// Can occur when writing to `stderr` or `stdout` or reading a configuration file.
+    ///
+    /// [I/O error]: std::io::Error
+    Io,
+
+    /// Represents a [Format error] (which is a part of [`Display`]).
+    /// Typically caused by writing to `stderr` or `stdout`.
+    ///
+    /// [`Display`]: std::fmt::Display
+    /// [Format error]: std::fmt::Error
+    Format,
+}
+
+impl ErrorKind {
+    /// End-user description of the error case, where relevant
+    pub fn as_str(self) -> Option<&'static str> {
+        match self {
+            Self::InvalidValue => Some("One of the values isn't valid for an argument"),
+            Self::UnknownArgument => {
+                Some("Found an argument which wasn't expected or isn't valid in this context")
+            }
+            Self::InvalidSubcommand => Some("A subcommand wasn't recognized"),
+            Self::UnrecognizedSubcommand => Some("A subcommand wasn't recognized"),
+            Self::EmptyValue => Some("An argument requires a value but none was supplied"),
+            Self::NoEquals => Some("Equal is needed when assigning values to one of the arguments"),
+            Self::ValueValidation => Some("Invalid value for one of the arguments"),
+            Self::TooManyValues => Some("An argument received an unexpected value"),
+            Self::TooFewValues => Some("An argument requires more values"),
+            Self::TooManyOccurrences => Some("An argument occurred too many times"),
+            Self::WrongNumberOfValues => Some("An argument received too many or too few values"),
+            Self::ArgumentConflict => {
+                Some("An argument cannot be used with one or more of the other specified arguments")
+            }
+            Self::MissingRequiredArgument => {
+                Some("One or more required arguments were not provided")
+            }
+            Self::MissingSubcommand => Some("A subcommand is required but one was not provided"),
+            Self::UnexpectedMultipleUsage => {
+                Some("An argument was provided more than once but cannot be used multiple times")
+            }
+            Self::InvalidUtf8 => Some("Invalid UTF-8 was detected in one or more arguments"),
+            Self::DisplayHelp => None,
+            Self::DisplayHelpOnMissingArgumentOrSubcommand => None,
+            Self::DisplayVersion => None,
+            Self::ArgumentNotFound => Some("An argument wasn't found"),
+            Self::Io => None,
+            Self::Format => None,
+        }
+    }
+}
+
+impl std::fmt::Display for ErrorKind {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.as_str().unwrap_or_default().fmt(f)
+    }
+}
diff --git a/vendor/clap-3.2.20/src/error/mod.rs b/vendor/clap-3.2.20/src/error/mod.rs
new file mode 100644
index 000000000..fbd2b30a8
--- /dev/null
+++ b/vendor/clap-3.2.20/src/error/mod.rs
@@ -0,0 +1,1153 @@
+//! Error reporting
+#![allow(deprecated)]
+
+// Std
+use std::{
+    borrow::Cow,
+    convert::From,
+    error,
+    fmt::{self, Debug, Display, Formatter},
+    io::{self, BufRead},
+    result::Result as StdResult,
+};
+
+// Internal
+use crate::output::fmt::Colorizer;
+use crate::output::fmt::Stream;
+use crate::parser::features::suggestions;
+use crate::util::{color::ColorChoice, safe_exit, SUCCESS_CODE, USAGE_CODE};
+use crate::AppSettings;
+use crate::Command;
+
+mod context;
+mod kind;
+
+pub use context::ContextKind;
+pub use context::ContextValue;
+pub use kind::ErrorKind;
+
+/// Short hand for [`Result`] type
+///
+/// [`Result`]: std::result::Result
+pub type Result<T, E = Error> = StdResult<T, E>;
+
+/// Command Line Argument Parser Error
+///
+/// See [`Command::error`] to create an error.
+///
+/// [`Command::error`]: crate::Command::error
+#[derive(Debug)]
+pub struct Error {
+    inner: Box<ErrorInner>,
+    /// Deprecated, replaced with [`Error::kind()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Error::kind()`")
+    )]
+    pub kind: ErrorKind,
+    /// Deprecated, replaced with [`Error::context()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.1.0", note = "Replaced with `Error::context()`")
+    )]
+    pub info: Vec<String>,
+}
+
+#[derive(Debug)]
+struct ErrorInner {
+    kind: ErrorKind,
+    context: Vec<(ContextKind, ContextValue)>,
+    message: Option<Message>,
+    source: Option<Box<dyn error::Error + Send + Sync>>,
+    help_flag: Option<&'static str>,
+    color_when: ColorChoice,
+    wait_on_exit: bool,
+    backtrace: Option<Backtrace>,
+}
+
+impl Error {
+    /// Create an unformatted error
+    ///
+    /// This is for you need to pass the error up to
+    /// a place that has access to the `Command` at which point you can call [`Error::format`].
+    ///
+    /// Prefer [`Command::error`] for generating errors.
+    ///
+    /// [`Command::error`]: crate::Command::error
+    pub fn raw(kind: ErrorKind, message: impl std::fmt::Display) -> Self {
+        Self::new(kind).set_message(message.to_string())
+    }
+
+    /// Format the existing message with the Command's context
+    #[must_use]
+    pub fn format(mut self, cmd: &mut Command) -> Self {
+        cmd._build_self();
+        let usage = cmd.render_usage();
+        if let Some(message) = self.inner.message.as_mut() {
+            message.format(cmd, usage);
+        }
+        self.with_cmd(cmd)
+    }
+
+    /// Type of error for programmatic processing
+    pub fn kind(&self) -> ErrorKind {
+        self.inner.kind
+    }
+
+    /// Additional information to further qualify the error
+    pub fn context(&self) -> impl Iterator<Item = (ContextKind, &ContextValue)> {
+        self.inner.context.iter().map(|(k, v)| (*k, v))
+    }
+
+    /// Should the message be written to `stdout` or not?
+    #[inline]
+    pub fn use_stderr(&self) -> bool {
+        self.stream() == Stream::Stderr
+    }
+
+    pub(crate) fn stream(&self) -> Stream {
+        match self.kind() {
+            ErrorKind::DisplayHelp | ErrorKind::DisplayVersion => Stream::Stdout,
+            _ => Stream::Stderr,
+        }
+    }
+
+    /// Prints the error and exits.
+    ///
+    /// Depending on the error kind, this either prints to `stderr` and exits with a status of `2`
+    /// or prints to `stdout` and exits with a status of `0`.
+    pub fn exit(&self) -> ! {
+        if self.use_stderr() {
+            // Swallow broken pipe errors
+            let _ = self.print();
+
+            if self.inner.wait_on_exit {
+                wlnerr!("\nPress [ENTER] / [RETURN] to continue...");
+                let mut s = String::new();
+                let i = io::stdin();
+                i.lock().read_line(&mut s).unwrap();
+            }
+
+            safe_exit(USAGE_CODE);
+        }
+
+        // Swallow broken pipe errors
+        let _ = self.print();
+        safe_exit(SUCCESS_CODE)
+    }
+
+    /// Prints formatted and colored error to `stdout` or `stderr` according to its error kind
+    ///
+    /// # Example
+    /// ```no_run
+    /// use clap::Command;
+    ///
+    /// match Command::new("Command").try_get_matches() {
+    ///     Ok(matches) => {
+    ///         // do_something
+    ///     },
+    ///     Err(err) => {
+    ///         err.print().expect("Error writing Error");
+    ///         // do_something
+    ///     },
+    /// };
+    /// ```
+    pub fn print(&self) -> io::Result<()> {
+        self.formatted().print()
+    }
+
+    /// Deprecated, replaced with [`Command::error`]
+    ///
+    /// [`Command::error`]: crate::Command::error
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Command::error`")
+    )]
+    #[doc(hidden)]
+    pub fn with_description(description: String, kind: ErrorKind) -> Self {
+        Error::raw(kind, description)
+    }
+
+    fn new(kind: ErrorKind) -> Self {
+        Self {
+            inner: Box::new(ErrorInner {
+                kind,
+                context: Vec::new(),
+                message: None,
+                source: None,
+                help_flag: None,
+                color_when: ColorChoice::Never,
+                wait_on_exit: false,
+                backtrace: Backtrace::new(),
+            }),
+            kind,
+            info: vec![],
+        }
+    }
+
+    #[inline(never)]
+    fn for_app(kind: ErrorKind, cmd: &Command, colorizer: Colorizer, info: Vec<String>) -> Self {
+        Self::new(kind)
+            .set_message(colorizer)
+            .with_cmd(cmd)
+            .set_info(info)
+    }
+
+    pub(crate) fn with_cmd(self, cmd: &Command) -> Self {
+        self.set_wait_on_exit(cmd.is_set(AppSettings::WaitOnError))
+            .set_color(cmd.get_color())
+            .set_help_flag(get_help_flag(cmd))
+    }
+
+    pub(crate) fn set_message(mut self, message: impl Into<Message>) -> Self {
+        self.inner.message = Some(message.into());
+        self
+    }
+
+    pub(crate) fn set_info(mut self, info: Vec<String>) -> Self {
+        self.info = info;
+        self
+    }
+
+    pub(crate) fn set_source(mut self, source: Box<dyn error::Error + Send + Sync>) -> Self {
+        self.inner.source = Some(source);
+        self
+    }
+
+    pub(crate) fn set_color(mut self, color_when: ColorChoice) -> Self {
+        self.inner.color_when = color_when;
+        self
+    }
+
+    pub(crate) fn set_help_flag(mut self, help_flag: Option<&'static str>) -> Self {
+        self.inner.help_flag = help_flag;
+        self
+    }
+
+    pub(crate) fn set_wait_on_exit(mut self, yes: bool) -> Self {
+        self.inner.wait_on_exit = yes;
+        self
+    }
+
+    /// Does not verify if `ContextKind` is already present
+    #[inline(never)]
+    pub(crate) fn insert_context_unchecked(
+        mut self,
+        kind: ContextKind,
+        value: ContextValue,
+    ) -> Self {
+        self.inner.context.push((kind, value));
+        self
+    }
+
+    /// Does not verify if `ContextKind` is already present
+    #[inline(never)]
+    pub(crate) fn extend_context_unchecked<const N: usize>(
+        mut self,
+        context: [(ContextKind, ContextValue); N],
+    ) -> Self {
+        self.inner.context.extend(context);
+        self
+    }
+
+    #[inline(never)]
+    fn get_context(&self, kind: ContextKind) -> Option<&ContextValue> {
+        self.inner
+            .context
+            .iter()
+            .find_map(|(k, v)| (*k == kind).then(|| v))
+    }
+
+    pub(crate) fn display_help(cmd: &Command, colorizer: Colorizer) -> Self {
+        Self::for_app(ErrorKind::DisplayHelp, cmd, colorizer, vec![])
+    }
+
+    pub(crate) fn display_help_error(cmd: &Command, colorizer: Colorizer) -> Self {
+        Self::for_app(
+            ErrorKind::DisplayHelpOnMissingArgumentOrSubcommand,
+            cmd,
+            colorizer,
+            vec![],
+        )
+    }
+
+    pub(crate) fn display_version(cmd: &Command, colorizer: Colorizer) -> Self {
+        Self::for_app(ErrorKind::DisplayVersion, cmd, colorizer, vec![])
+    }
+
+    pub(crate) fn argument_conflict(
+        cmd: &Command,
+        arg: String,
+        mut others: Vec<String>,
+        usage: String,
+    ) -> Self {
+        let info = others.clone();
+        let others = match others.len() {
+            0 => ContextValue::None,
+            1 => ContextValue::String(others.pop().unwrap()),
+            _ => ContextValue::Strings(others),
+        };
+        Self::new(ErrorKind::ArgumentConflict)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (ContextKind::PriorArg, others),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn empty_value(cmd: &Command, good_vals: &[&str], arg: String) -> Self {
+        let info = vec![arg.clone()];
+        let mut err = Self::new(ErrorKind::EmptyValue)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([(ContextKind::InvalidArg, ContextValue::String(arg))]);
+        if !good_vals.is_empty() {
+            err = err.insert_context_unchecked(
+                ContextKind::ValidValue,
+                ContextValue::Strings(good_vals.iter().map(|s| (*s).to_owned()).collect()),
+            );
+        }
+        err
+    }
+
+    pub(crate) fn no_equals(cmd: &Command, arg: String, usage: String) -> Self {
+        let info = vec![arg.clone()];
+        Self::new(ErrorKind::NoEquals)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn invalid_value(
+        cmd: &Command,
+        bad_val: String,
+        good_vals: &[&str],
+        arg: String,
+    ) -> Self {
+        let mut info = vec![arg.clone(), bad_val.clone()];
+        info.extend(good_vals.iter().map(|s| (*s).to_owned()));
+
+        let suggestion = suggestions::did_you_mean(&bad_val, good_vals.iter()).pop();
+        let mut err = Self::new(ErrorKind::InvalidValue)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (ContextKind::InvalidValue, ContextValue::String(bad_val)),
+                (
+                    ContextKind::ValidValue,
+                    ContextValue::Strings(good_vals.iter().map(|s| (*s).to_owned()).collect()),
+                ),
+            ]);
+        if let Some(suggestion) = suggestion {
+            err = err.insert_context_unchecked(
+                ContextKind::SuggestedValue,
+                ContextValue::String(suggestion),
+            );
+        }
+        err
+    }
+
+    pub(crate) fn invalid_subcommand(
+        cmd: &Command,
+        subcmd: String,
+        did_you_mean: String,
+        name: String,
+        usage: String,
+    ) -> Self {
+        let info = vec![subcmd.clone()];
+        let suggestion = format!("{} -- {}", name, subcmd);
+        Self::new(ErrorKind::InvalidSubcommand)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidSubcommand, ContextValue::String(subcmd)),
+                (
+                    ContextKind::SuggestedSubcommand,
+                    ContextValue::String(did_you_mean),
+                ),
+                (
+                    ContextKind::SuggestedCommand,
+                    ContextValue::String(suggestion),
+                ),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn unrecognized_subcommand(cmd: &Command, subcmd: String, usage: String) -> Self {
+        let info = vec![subcmd.clone()];
+        Self::new(ErrorKind::UnrecognizedSubcommand)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidSubcommand, ContextValue::String(subcmd)),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn missing_required_argument(
+        cmd: &Command,
+        required: Vec<String>,
+        usage: String,
+    ) -> Self {
+        let info = required.clone();
+        Self::new(ErrorKind::MissingRequiredArgument)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::Strings(required)),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn missing_subcommand(cmd: &Command, name: String, usage: String) -> Self {
+        let info = vec![];
+        Self::new(ErrorKind::MissingSubcommand)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidSubcommand, ContextValue::String(name)),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn invalid_utf8(cmd: &Command, usage: String) -> Self {
+        let info = vec![];
+        Self::new(ErrorKind::InvalidUtf8)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([(ContextKind::Usage, ContextValue::String(usage))])
+    }
+
+    pub(crate) fn too_many_occurrences(
+        cmd: &Command,
+        arg: String,
+        max_occurs: usize,
+        curr_occurs: usize,
+        usage: String,
+    ) -> Self {
+        let info = vec![arg.clone(), curr_occurs.to_string(), max_occurs.to_string()];
+        Self::new(ErrorKind::TooManyOccurrences)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (
+                    ContextKind::MaxOccurrences,
+                    ContextValue::Number(max_occurs as isize),
+                ),
+                (
+                    ContextKind::ActualNumValues,
+                    ContextValue::Number(curr_occurs as isize),
+                ),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn too_many_values(cmd: &Command, val: String, arg: String, usage: String) -> Self {
+        let info = vec![arg.clone(), val.clone()];
+        Self::new(ErrorKind::TooManyValues)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (ContextKind::InvalidValue, ContextValue::String(val)),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn too_few_values(
+        cmd: &Command,
+        arg: String,
+        min_vals: usize,
+        curr_vals: usize,
+        usage: String,
+    ) -> Self {
+        let info = vec![arg.clone(), curr_vals.to_string(), min_vals.to_string()];
+        Self::new(ErrorKind::TooFewValues)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (
+                    ContextKind::MinValues,
+                    ContextValue::Number(min_vals as isize),
+                ),
+                (
+                    ContextKind::ActualNumValues,
+                    ContextValue::Number(curr_vals as isize),
+                ),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn value_validation(
+        arg: String,
+        val: String,
+        err: Box<dyn error::Error + Send + Sync>,
+    ) -> Self {
+        let info = vec![arg.clone(), val.to_string(), err.to_string()];
+        Self::new(ErrorKind::ValueValidation)
+            .set_info(info)
+            .set_source(err)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (ContextKind::InvalidValue, ContextValue::String(val)),
+            ])
+    }
+
+    pub(crate) fn wrong_number_of_values(
+        cmd: &Command,
+        arg: String,
+        num_vals: usize,
+        curr_vals: usize,
+        usage: String,
+    ) -> Self {
+        let info = vec![arg.clone(), curr_vals.to_string(), num_vals.to_string()];
+        Self::new(ErrorKind::WrongNumberOfValues)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (
+                    ContextKind::ExpectedNumValues,
+                    ContextValue::Number(num_vals as isize),
+                ),
+                (
+                    ContextKind::ActualNumValues,
+                    ContextValue::Number(curr_vals as isize),
+                ),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn unexpected_multiple_usage(cmd: &Command, arg: String, usage: String) -> Self {
+        let info = vec![arg.clone()];
+        Self::new(ErrorKind::UnexpectedMultipleUsage)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn unknown_argument(
+        cmd: &Command,
+        arg: String,
+        did_you_mean: Option<(String, Option<String>)>,
+        usage: String,
+    ) -> Self {
+        let info = vec![arg.clone()];
+        let mut err = Self::new(ErrorKind::UnknownArgument)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ]);
+        if let Some((flag, sub)) = did_you_mean {
+            err = err.insert_context_unchecked(
+                ContextKind::SuggestedArg,
+                ContextValue::String(format!("--{}", flag)),
+            );
+            if let Some(sub) = sub {
+                err = err.insert_context_unchecked(
+                    ContextKind::SuggestedSubcommand,
+                    ContextValue::String(sub),
+                );
+            }
+        }
+        err
+    }
+
+    pub(crate) fn unnecessary_double_dash(cmd: &Command, arg: String, usage: String) -> Self {
+        let info = vec![arg.clone()];
+        Self::new(ErrorKind::UnknownArgument)
+            .with_cmd(cmd)
+            .set_info(info)
+            .extend_context_unchecked([
+                (ContextKind::InvalidArg, ContextValue::String(arg)),
+                (ContextKind::TrailingArg, ContextValue::Bool(true)),
+                (ContextKind::Usage, ContextValue::String(usage)),
+            ])
+    }
+
+    pub(crate) fn argument_not_found_auto(arg: String) -> Self {
+        let info = vec![arg.clone()];
+        Self::new(ErrorKind::ArgumentNotFound)
+            .set_info(info)
+            .extend_context_unchecked([(ContextKind::InvalidArg, ContextValue::String(arg))])
+    }
+
+    fn formatted(&self) -> Cow<'_, Colorizer> {
+        if let Some(message) = self.inner.message.as_ref() {
+            message.formatted()
+        } else {
+            let mut c = Colorizer::new(self.stream(), self.inner.color_when);
+
+            start_error(&mut c);
+
+            if !self.write_dynamic_context(&mut c) {
+                if let Some(msg) = self.kind().as_str() {
+                    c.none(msg.to_owned());
+                } else if let Some(source) = self.inner.source.as_ref() {
+                    c.none(source.to_string());
+                } else {
+                    c.none("Unknown cause");
+                }
+            }
+
+            let usage = self.get_context(ContextKind::Usage);
+            if let Some(ContextValue::String(usage)) = usage {
+                put_usage(&mut c, usage);
+            }
+
+            try_help(&mut c, self.inner.help_flag);
+
+            Cow::Owned(c)
+        }
+    }
+
+    #[must_use]
+    fn write_dynamic_context(&self, c: &mut Colorizer) -> bool {
+        match self.kind() {
+            ErrorKind::ArgumentConflict => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                let prior_arg = self.get_context(ContextKind::PriorArg);
+                if let (Some(ContextValue::String(invalid_arg)), Some(prior_arg)) =
+                    (invalid_arg, prior_arg)
+                {
+                    c.none("The argument '");
+                    c.warning(invalid_arg);
+                    c.none("' cannot be used with");
+
+                    match prior_arg {
+                        ContextValue::Strings(values) => {
+                            c.none(":");
+                            for v in values {
+                                c.none("\n    ");
+                                c.warning(&**v);
+                            }
+                        }
+                        ContextValue::String(value) => {
+                            c.none(" '");
+                            c.warning(value);
+                            c.none("'");
+                        }
+                        _ => {
+                            c.none(" one or more of the other specified arguments");
+                        }
+                    }
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::EmptyValue => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                if let Some(ContextValue::String(invalid_arg)) = invalid_arg {
+                    c.none("The argument '");
+                    c.warning(invalid_arg);
+                    c.none("' requires a value but none was supplied");
+
+                    let possible_values = self.get_context(ContextKind::ValidValue);
+                    if let Some(ContextValue::Strings(possible_values)) = possible_values {
+                        c.none("\n\t[possible values: ");
+                        if let Some((last, elements)) = possible_values.split_last() {
+                            for v in elements {
+                                c.good(escape(v));
+                                c.none(", ");
+                            }
+                            c.good(escape(last));
+                        }
+                        c.none("]");
+                    }
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::NoEquals => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                if let Some(ContextValue::String(invalid_arg)) = invalid_arg {
+                    c.none("Equal sign is needed when assigning values to '");
+                    c.warning(invalid_arg);
+                    c.none("'.");
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::InvalidValue => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                let invalid_value = self.get_context(ContextKind::InvalidValue);
+                if let (
+                    Some(ContextValue::String(invalid_arg)),
+                    Some(ContextValue::String(invalid_value)),
+                ) = (invalid_arg, invalid_value)
+                {
+                    c.none(quote(invalid_value));
+                    c.none(" isn't a valid value for '");
+                    c.warning(invalid_arg);
+                    c.none("'");
+
+                    let possible_values = self.get_context(ContextKind::ValidValue);
+                    if let Some(ContextValue::Strings(possible_values)) = possible_values {
+                        c.none("\n\t[possible values: ");
+                        if let Some((last, elements)) = possible_values.split_last() {
+                            for v in elements {
+                                c.good(escape(v));
+                                c.none(", ");
+                            }
+                            c.good(escape(last));
+                        }
+                        c.none("]");
+                    }
+
+                    let suggestion = self.get_context(ContextKind::SuggestedValue);
+                    if let Some(ContextValue::String(suggestion)) = suggestion {
+                        c.none("\n\n\tDid you mean ");
+                        c.good(quote(suggestion));
+                        c.none("?");
+                    }
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::InvalidSubcommand => {
+                let invalid_sub = self.get_context(ContextKind::InvalidSubcommand);
+                if let Some(ContextValue::String(invalid_sub)) = invalid_sub {
+                    c.none("The subcommand '");
+                    c.warning(invalid_sub);
+                    c.none("' wasn't recognized");
+
+                    let valid_sub = self.get_context(ContextKind::SuggestedSubcommand);
+                    if let Some(ContextValue::String(valid_sub)) = valid_sub {
+                        c.none("\n\n\tDid you mean ");
+                        c.good(valid_sub);
+                        c.none("?");
+                    }
+
+                    let suggestion = self.get_context(ContextKind::SuggestedCommand);
+                    if let Some(ContextValue::String(suggestion)) = suggestion {
+                        c.none(
+            "\n\nIf you believe you received this message in error, try re-running with '",
+        );
+                        c.good(suggestion);
+                        c.none("'");
+                    }
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::UnrecognizedSubcommand => {
+                let invalid_sub = self.get_context(ContextKind::InvalidSubcommand);
+                if let Some(ContextValue::String(invalid_sub)) = invalid_sub {
+                    c.none("The subcommand '");
+                    c.warning(invalid_sub);
+                    c.none("' wasn't recognized");
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::MissingRequiredArgument => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                if let Some(ContextValue::Strings(invalid_arg)) = invalid_arg {
+                    c.none("The following required arguments were not provided:");
+                    for v in invalid_arg {
+                        c.none("\n    ");
+                        c.good(&**v);
+                    }
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::MissingSubcommand => {
+                let invalid_sub = self.get_context(ContextKind::InvalidSubcommand);
+                if let Some(ContextValue::String(invalid_sub)) = invalid_sub {
+                    c.none("'");
+                    c.warning(invalid_sub);
+                    c.none("' requires a subcommand but one was not provided");
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::InvalidUtf8 => false,
+            ErrorKind::TooManyOccurrences => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                let actual_num_occurs = self.get_context(ContextKind::ActualNumOccurrences);
+                let max_occurs = self.get_context(ContextKind::MaxOccurrences);
+                if let (
+                    Some(ContextValue::String(invalid_arg)),
+                    Some(ContextValue::Number(actual_num_occurs)),
+                    Some(ContextValue::Number(max_occurs)),
+                ) = (invalid_arg, actual_num_occurs, max_occurs)
+                {
+                    let were_provided = Error::singular_or_plural(*actual_num_occurs as usize);
+                    c.none("The argument '");
+                    c.warning(invalid_arg);
+                    c.none("' allows at most ");
+                    c.warning(max_occurs.to_string());
+                    c.none(" occurrences but ");
+                    c.warning(actual_num_occurs.to_string());
+                    c.none(were_provided);
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::TooManyValues => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                let invalid_value = self.get_context(ContextKind::InvalidValue);
+                if let (
+                    Some(ContextValue::String(invalid_arg)),
+                    Some(ContextValue::String(invalid_value)),
+                ) = (invalid_arg, invalid_value)
+                {
+                    c.none("The value '");
+                    c.warning(invalid_value);
+                    c.none("' was provided to '");
+                    c.warning(invalid_arg);
+                    c.none("' but it wasn't expecting any more values");
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::TooFewValues => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                let actual_num_values = self.get_context(ContextKind::ActualNumValues);
+                let min_values = self.get_context(ContextKind::MinValues);
+                if let (
+                    Some(ContextValue::String(invalid_arg)),
+                    Some(ContextValue::Number(actual_num_values)),
+                    Some(ContextValue::Number(min_values)),
+                ) = (invalid_arg, actual_num_values, min_values)
+                {
+                    let were_provided = Error::singular_or_plural(*actual_num_values as usize);
+                    c.none("The argument '");
+                    c.warning(invalid_arg);
+                    c.none("' requires at least ");
+                    c.warning(min_values.to_string());
+                    c.none(" values but only ");
+                    c.warning(actual_num_values.to_string());
+                    c.none(were_provided);
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::ValueValidation => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                let invalid_value = self.get_context(ContextKind::InvalidValue);
+                if let (
+                    Some(ContextValue::String(invalid_arg)),
+                    Some(ContextValue::String(invalid_value)),
+                ) = (invalid_arg, invalid_value)
+                {
+                    c.none("Invalid value ");
+                    c.warning(quote(invalid_value));
+                    c.none(" for '");
+                    c.warning(invalid_arg);
+                    if let Some(source) = self.inner.source.as_deref() {
+                        c.none("': ");
+                        c.none(source.to_string());
+                    } else {
+                        c.none("'");
+                    }
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::WrongNumberOfValues => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                let actual_num_values = self.get_context(ContextKind::ActualNumValues);
+                let num_values = self.get_context(ContextKind::ExpectedNumValues);
+                if let (
+                    Some(ContextValue::String(invalid_arg)),
+                    Some(ContextValue::Number(actual_num_values)),
+                    Some(ContextValue::Number(num_values)),
+                ) = (invalid_arg, actual_num_values, num_values)
+                {
+                    let were_provided = Error::singular_or_plural(*actual_num_values as usize);
+                    c.none("The argument '");
+                    c.warning(invalid_arg);
+                    c.none("' requires ");
+                    c.warning(num_values.to_string());
+                    c.none(" values, but ");
+                    c.warning(actual_num_values.to_string());
+                    c.none(were_provided);
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::UnexpectedMultipleUsage => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                if let Some(ContextValue::String(invalid_arg)) = invalid_arg {
+                    c.none("The argument '");
+                    c.warning(invalid_arg.to_string());
+                    c.none("' was provided more than once, but cannot be used multiple times");
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::UnknownArgument => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                if let Some(ContextValue::String(invalid_arg)) = invalid_arg {
+                    c.none("Found argument '");
+                    c.warning(invalid_arg.to_string());
+                    c.none("' which wasn't expected, or isn't valid in this context");
+
+                    let valid_sub = self.get_context(ContextKind::SuggestedSubcommand);
+                    let valid_arg = self.get_context(ContextKind::SuggestedArg);
+                    match (valid_sub, valid_arg) {
+                        (
+                            Some(ContextValue::String(valid_sub)),
+                            Some(ContextValue::String(valid_arg)),
+                        ) => {
+                            c.none("\n\n\tDid you mean ");
+                            c.none("to put '");
+                            c.good(valid_arg);
+                            c.none("' after the subcommand '");
+                            c.good(valid_sub);
+                            c.none("'?");
+                        }
+                        (None, Some(ContextValue::String(valid_arg))) => {
+                            c.none("\n\n\tDid you mean '");
+                            c.good(valid_arg);
+                            c.none("'?");
+                        }
+                        (_, _) => {}
+                    }
+
+                    let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                    if let Some(ContextValue::String(invalid_arg)) = invalid_arg {
+                        if invalid_arg.starts_with('-') {
+                            c.none(format!(
+                                "\n\n\tIf you tried to supply `{}` as a value rather than a flag, use `-- {}`",
+                                invalid_arg, invalid_arg
+                            ));
+                        }
+
+                        let trailing_arg = self.get_context(ContextKind::TrailingArg);
+                        if trailing_arg == Some(&ContextValue::Bool(true)) {
+                            c.none(format!(
+                            "\n\n\tIf you tried to supply `{}` as a subcommand, remove the '--' before it.",
+                            invalid_arg
+                        ));
+                        }
+                    }
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::ArgumentNotFound => {
+                let invalid_arg = self.get_context(ContextKind::InvalidArg);
+                if let Some(ContextValue::String(invalid_arg)) = invalid_arg {
+                    c.none("The argument '");
+                    c.warning(invalid_arg.to_string());
+                    c.none("' wasn't found");
+                    true
+                } else {
+                    false
+                }
+            }
+            ErrorKind::DisplayHelp
+            | ErrorKind::DisplayHelpOnMissingArgumentOrSubcommand
+            | ErrorKind::DisplayVersion
+            | ErrorKind::Io
+            | ErrorKind::Format => false,
+        }
+    }
+
+    /// Returns the singular or plural form on the verb to be based on the argument's value.
+    fn singular_or_plural(n: usize) -> &'static str {
+        if n > 1 {
+            " were provided"
+        } else {
+            " was provided"
+        }
+    }
+}
+
+impl From<io::Error> for Error {
+    fn from(e: io::Error) -> Self {
+        Error::raw(ErrorKind::Io, e)
+    }
+}
+
+impl From<fmt::Error> for Error {
+    fn from(e: fmt::Error) -> Self {
+        Error::raw(ErrorKind::Format, e)
+    }
+}
+
+impl error::Error for Error {
+    #[allow(trivial_casts)]
+    fn source(&self) -> Option<&(dyn error::Error + 'static)> {
+        self.inner.source.as_ref().map(|e| e.as_ref() as _)
+    }
+}
+
+impl Display for Error {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        // Assuming `self.message` already has a trailing newline, from `try_help` or similar
+        write!(f, "{}", self.formatted())?;
+        if let Some(backtrace) = self.inner.backtrace.as_ref() {
+            writeln!(f)?;
+            writeln!(f, "Backtrace:")?;
+            writeln!(f, "{}", backtrace)?;
+        }
+        Ok(())
+    }
+}
+
+fn start_error(c: &mut Colorizer) {
+    c.error("error:");
+    c.none(" ");
+}
+
+fn put_usage(c: &mut Colorizer, usage: impl Into<String>) {
+    c.none("\n\n");
+    c.none(usage);
+}
+
+fn get_help_flag(cmd: &Command) -> Option<&'static str> {
+    if !cmd.is_disable_help_flag_set() {
+        Some("--help")
+    } else if cmd.has_subcommands() && !cmd.is_disable_help_subcommand_set() {
+        Some("help")
+    } else {
+        None
+    }
+}
+
+fn try_help(c: &mut Colorizer, help: Option<&str>) {
+    if let Some(help) = help {
+        c.none("\n\nFor more information try ");
+        c.good(help);
+        c.none("\n");
+    } else {
+        c.none("\n");
+    }
+}
+
+fn quote(s: impl AsRef<str>) -> String {
+    let s = s.as_ref();
+    format!("{:?}", s)
+}
+
+fn escape(s: impl AsRef<str>) -> String {
+    let s = s.as_ref();
+    if s.contains(char::is_whitespace) {
+        quote(s)
+    } else {
+        s.to_owned()
+    }
+}
+
+#[derive(Clone, Debug)]
+pub(crate) enum Message {
+    Raw(String),
+    Formatted(Colorizer),
+}
+
+impl Message {
+    fn format(&mut self, cmd: &Command, usage: String) {
+        match self {
+            Message::Raw(s) => {
+                let mut c = Colorizer::new(Stream::Stderr, cmd.get_color());
+
+                let mut message = String::new();
+                std::mem::swap(s, &mut message);
+                start_error(&mut c);
+                c.none(message);
+                put_usage(&mut c, usage);
+                try_help(&mut c, get_help_flag(cmd));
+                *self = Self::Formatted(c);
+            }
+            Message::Formatted(_) => {}
+        }
+    }
+
+    fn formatted(&self) -> Cow<Colorizer> {
+        match self {
+            Message::Raw(s) => {
+                let mut c = Colorizer::new(Stream::Stderr, ColorChoice::Never);
+                start_error(&mut c);
+                c.none(s);
+                Cow::Owned(c)
+            }
+            Message::Formatted(c) => Cow::Borrowed(c),
+        }
+    }
+}
+
+impl From<String> for Message {
+    fn from(inner: String) -> Self {
+        Self::Raw(inner)
+    }
+}
+
+impl From<Colorizer> for Message {
+    fn from(inner: Colorizer) -> Self {
+        Self::Formatted(inner)
+    }
+}
+
+#[cfg(feature = "debug")]
+#[derive(Debug)]
+struct Backtrace(backtrace::Backtrace);
+
+#[cfg(feature = "debug")]
+impl Backtrace {
+    fn new() -> Option<Self> {
+        Some(Self(backtrace::Backtrace::new()))
+    }
+}
+
+#[cfg(feature = "debug")]
+impl Display for Backtrace {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        // `backtrace::Backtrace` uses `Debug` instead of `Display`
+        write!(f, "{:?}", self.0)
+    }
+}
+
+#[cfg(not(feature = "debug"))]
+#[derive(Debug)]
+struct Backtrace;
+
+#[cfg(not(feature = "debug"))]
+impl Backtrace {
+    fn new() -> Option<Self> {
+        None
+    }
+}
+
+#[cfg(not(feature = "debug"))]
+impl Display for Backtrace {
+    fn fmt(&self, _: &mut Formatter) -> fmt::Result {
+        Ok(())
+    }
+}
+
+#[test]
+fn check_auto_traits() {
+    static_assertions::assert_impl_all!(Error: Send, Sync, Unpin);
+}
diff --git a/vendor/clap-3.2.20/src/lib.rs b/vendor/clap-3.2.20/src/lib.rs
new file mode 100644
index 000000000..5cefe6ec1
--- /dev/null
+++ b/vendor/clap-3.2.20/src/lib.rs
@@ -0,0 +1,232 @@
+// Copyright ⓒ 2015-2016 Kevin B. Knapp and [`clap-rs` contributors](https://github.com/clap-rs/clap/graphs/contributors).
+// Licensed under the MIT license
+// (see LICENSE or <http://opensource.org/licenses/MIT>) All files in the project carrying such
+// notice may not be copied, modified, or distributed except according to those terms.
+
+//! > **Command Line Argument Parser for Rust**
+//!
+//! Quick Links:
+//! - Derive [tutorial][_derive::_tutorial] and [reference][_derive]
+//! - Builder [tutorial][_tutorial] and [reference](index.html)
+//! - [Cookbook][_cookbook]
+//! - [FAQ][_faq]
+//! - [Discussions](https://github.com/clap-rs/clap/discussions)
+//!
+//! ## Aspirations
+//!
+//! - Out of the box, users get a polished CLI experience
+//!   - Including common argument behavior, help generation, suggested fixes for users, colored output, [shell completions](https://github.com/clap-rs/clap/tree/master/clap_complete), etc
+//! - Flexible enough to port your existing CLI interface
+//!   - However, we won't necessarily streamline support for each use case
+//! - Reasonable parse performance
+//! - Resilient maintainership, including
+//!   - Willing to break compatibility rather than batching up breaking changes in large releases
+//!   - Leverage feature flags to keep to one active branch
+//!   - Being under [WG-CLI](https://github.com/rust-cli/team/) to increase the bus factor
+//! - We follow semver and will wait about 6-9 months between major breaking changes
+//! - We will support the last two minor Rust releases (MSRV, currently 1.56.1)
+//!
+//! While these aspirations can be at odds with fast build times and low binary
+//! size, we will still strive to keep these reasonable for the flexibility you
+//! get.  Check out the
+//! [argparse-benchmarks](https://github.com/rust-cli/argparse-benchmarks-rs) for
+//! CLI parsers optimized for other use cases.
+//!
+//! ## Example
+//!
+//! Run
+//! ```console
+//! $ cargo add clap --features derive
+//! ```
+//! *(See also [feature flag reference][_features])*
+//!
+//! Then define your CLI in `main.rs`:
+#![cfg_attr(not(feature = "derive"), doc = " ```ignore")]
+#![cfg_attr(feature = "derive", doc = " ```no_run")]
+#![doc = include_str!("../examples/demo.rs")]
+//! ```
+//!
+//! And try it out:
+#![doc = include_str!("../examples/demo.md")]
+//!
+//! See also the derive [tutorial][_derive::_tutorial] and [reference][_derive]
+//!
+//! ### Related Projects
+//!
+//! Augment clap:
+//! - [wild](https://crates.io/crates/wild) for supporting wildcards (`*`) on Windows like you do Linux
+//! - [argfile](https://crates.io/crates/argfile) for loading additional arguments from a file (aka response files)
+//! - [shadow-rs](https://crates.io/crates/shadow-rs) for generating `Command::long_version`
+//! - [clap_mangen](https://crates.io/crates/clap_mangen) for generating man page source (roff)
+//! - [clap_complete](https://crates.io/crates/clap_complete) for shell completion support
+//!
+//! CLI Helpers
+//! - [clap-verbosity-flag](https://crates.io/crates/clap-verbosity-flag)
+//! - [clap-cargo](https://crates.io/crates/clap-cargo)
+//! - [concolor-clap](https://crates.io/crates/concolor-clap)
+//!
+//! Testing
+//! - [`trycmd`](https://crates.io/crates/trycmd):  Bulk snapshot testing
+//! - [`snapbox`](https://crates.io/crates/snapbox):  Specialized snapshot testing
+//! - [`assert_cmd`](https://crates.io/crates/assert_cmd) and [`assert_fs`](https://crates.io/crates/assert_fs): Customized testing
+//!
+//! Documentation:
+//! - [Command-line Apps for Rust](https://rust-cli.github.io/book/index.html) book
+//!
+
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc(html_logo_url = "https://raw.githubusercontent.com/clap-rs/clap/master/assets/clap.png")]
+#![warn(
+    missing_docs,
+    missing_debug_implementations,
+    missing_copy_implementations,
+    trivial_casts,
+    unused_allocation,
+    trivial_numeric_casts,
+    clippy::single_char_pattern
+)]
+#![forbid(unsafe_code)]
+// HACK https://github.com/rust-lang/rust-clippy/issues/7290
+#![allow(clippy::single_component_path_imports)]
+#![allow(clippy::branches_sharing_code)]
+// Doesn't allow for debug statements, etc to be unique
+#![allow(clippy::if_same_then_else)]
+
+#[cfg(not(feature = "std"))]
+compile_error!("`std` feature is currently required to build `clap`");
+
+pub use crate::builder::ArgAction;
+pub use crate::builder::Command;
+pub use crate::builder::{Arg, ArgGroup};
+pub use crate::error::Error;
+pub use crate::parser::ArgMatches;
+#[cfg(feature = "color")]
+pub use crate::util::color::ColorChoice;
+#[cfg(not(feature = "color"))]
+#[allow(unused_imports)]
+pub(crate) use crate::util::color::ColorChoice;
+
+pub use crate::derive::{Args, CommandFactory, FromArgMatches, Parser, Subcommand, ValueEnum};
+
+#[allow(deprecated)]
+pub use crate::builder::App;
+pub use crate::builder::{AppFlags, AppSettings, ArgFlags, ArgSettings, PossibleValue, ValueHint};
+pub use crate::error::{ErrorKind, Result};
+#[allow(deprecated)]
+pub use crate::parser::{Indices, OsValues, ValueSource, Values};
+
+#[cfg(feature = "yaml")]
+#[doc(hidden)]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(
+        since = "3.0.0",
+        note = "Deprecated in Issue #3087, maybe clap::Parser would fit your use case?"
+    )
+)]
+#[doc(hidden)]
+pub use yaml_rust::YamlLoader;
+
+#[cfg(feature = "derive")]
+#[doc(hidden)]
+pub use clap_derive::{self, *};
+
+/// Deprecated, replaced with [`CommandFactory`]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.0.0", note = "Replaced with `CommandFactory`")
+)]
+pub use CommandFactory as IntoApp;
+/// Deprecated, replaced with [`Parser`]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.0.0", note = "Replaced with `Parser`")
+)]
+#[doc(hidden)]
+pub use Parser as StructOpt;
+/// Deprecated, replaced with [`ValueEnum`]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.2.0", note = "Replaced with `ValueEnum`")
+)]
+pub use ValueEnum as ArgEnum;
+
+#[cfg(feature = "unstable-doc")]
+pub mod _cookbook;
+#[cfg(feature = "unstable-doc")]
+pub mod _derive;
+#[cfg(feature = "unstable-doc")]
+pub mod _faq;
+#[cfg(feature = "unstable-doc")]
+pub mod _features;
+#[cfg(feature = "unstable-doc")]
+pub mod _tutorial;
+
+#[doc(hidden)]
+pub mod __macro_refs {
+    #[cfg(any(feature = "derive", feature = "cargo"))]
+    #[doc(hidden)]
+    pub use once_cell;
+}
+
+#[macro_use]
+#[allow(missing_docs)]
+mod macros;
+
+mod derive;
+
+#[cfg(feature = "regex")]
+pub use crate::builder::RegexRef;
+
+pub mod builder;
+pub mod error;
+pub mod parser;
+
+mod mkeymap;
+mod output;
+mod util;
+
+const INTERNAL_ERROR_MSG: &str = "Fatal internal error. Please consider filing a bug \
+                                  report at https://github.com/clap-rs/clap/issues";
+const INVALID_UTF8: &str = "unexpected invalid UTF-8 code point";
+
+/// Deprecated, replaced with [`Command::new`], unless you were looking for [Subcommand]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(
+        since = "3.0.0",
+        note = "Replaced with `Command::new` unless you intended the `Subcommand` trait"
+    )
+)]
+#[doc(hidden)]
+#[derive(Debug, Copy, Clone)]
+pub struct SubCommand {}
+
+#[allow(deprecated)]
+impl SubCommand {
+    /// Deprecated, replaced with [`Command::new`].
+    /// Did you mean Subcommand (lower-case c)?
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.0.0", note = "Replaced with `Command::new`")
+    )]
+    #[doc(hidden)]
+    pub fn with_name<'help>(name: &str) -> App<'help> {
+        Command::new(name)
+    }
+
+    /// Deprecated in [Issue #3087](https://github.com/clap-rs/clap/issues/3087), maybe [`clap::Parser`][crate::Parser] would fit your use case?
+    #[cfg(feature = "yaml")]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.0.0",
+            note = "Deprecated in Issue #3087, maybe clap::Parser would fit your use case?"
+        )
+    )]
+    #[doc(hidden)]
+    pub fn from_yaml(yaml: &yaml_rust::Yaml) -> App {
+        #![allow(deprecated)]
+        Command::from_yaml(yaml)
+    }
+}
diff --git a/vendor/clap-3.2.20/src/macros.rs b/vendor/clap-3.2.20/src/macros.rs
new file mode 100644
index 000000000..1f9167408
--- /dev/null
+++ b/vendor/clap-3.2.20/src/macros.rs
@@ -0,0 +1,1058 @@
+/// Deprecated in [Issue #3087](https://github.com/clap-rs/clap/issues/3087), maybe [`clap::Parser`][crate::Parser] would fit your use case?
+#[cfg(feature = "yaml")]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(
+        since = "3.0.0",
+        note = "Deprecated in Issue #3087, maybe clap::Parser would fit your use case?"
+    )
+)]
+#[doc(hidden)]
+#[macro_export]
+macro_rules! load_yaml {
+    ($yaml:expr) => {
+        &$crate::YamlLoader::load_from_str(include_str!($yaml)).expect("failed to load YAML file")
+            [0]
+    };
+}
+
+/// Deprecated, replaced with [`ArgMatches::value_of_t`][crate::ArgMatches::value_of_t]
+#[macro_export]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.0.0", note = "Replaced with `ArgMatches::get_one`")
+)]
+#[doc(hidden)]
+macro_rules! value_t {
+    ($m:ident, $v:expr, $t:ty) => {
+        $crate::value_t!($m.value_of($v), $t)
+    };
+    ($m:ident.value_of($v:expr), $t:ty) => {
+        $m.value_of_t::<$t>($v)
+    };
+}
+
+/// Deprecated, replaced with [`ArgMatches::value_of_t_or_exit`][crate::ArgMatches::value_of_t_or_exit]
+#[macro_export]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.0.0", note = "Replaced with `ArgMatches::get_one`")
+)]
+#[doc(hidden)]
+macro_rules! value_t_or_exit {
+    ($m:ident, $v:expr, $t:ty) => {
+        value_t_or_exit!($m.value_of($v), $t)
+    };
+    ($m:ident.value_of($v:expr), $t:ty) => {
+        $m.value_of_t_or_exit::<$t>($v)
+    };
+}
+
+/// Deprecated, replaced with [`ArgMatches::values_of_t`][crate::ArgMatches::value_of_t]
+#[macro_export]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.0.0", note = "Replaced with `ArgMatches::get_many`")
+)]
+#[doc(hidden)]
+macro_rules! values_t {
+    ($m:ident, $v:expr, $t:ty) => {
+        values_t!($m.values_of($v), $t)
+    };
+    ($m:ident.values_of($v:expr), $t:ty) => {
+        $m.values_of_t::<$t>($v)
+    };
+}
+
+/// Deprecated, replaced with [`ArgMatches::values_of_t_or_exit`][crate::ArgMatches::value_of_t_or_exit]
+#[macro_export]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.0.0", note = "Replaced with `ArgMatches::get_many`")
+)]
+#[doc(hidden)]
+macro_rules! values_t_or_exit {
+    ($m:ident, $v:expr, $t:ty) => {
+        values_t_or_exit!($m.values_of($v), $t)
+    };
+    ($m:ident.values_of($v:expr), $t:ty) => {
+        $m.values_of_t_or_exit::<$t>($v)
+    };
+}
+
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.0.0", note = "Replaced with `ValueEnum`")
+)]
+#[doc(hidden)]
+#[macro_export]
+macro_rules! _clap_count_exprs {
+    () => { 0 };
+    ($e:expr) => { 1 };
+    ($e:expr, $($es:expr),+) => { 1 + $crate::_clap_count_exprs!($($es),*) };
+}
+
+/// Deprecated, replaced with [`ArgEnum`][crate::ArgEnum]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.0.0", note = "Replaced with `ValueEnum`")
+)]
+#[doc(hidden)]
+#[macro_export]
+macro_rules! arg_enum {
+    (@as_item $($i:item)*) => ($($i)*);
+    (@impls ( $($tts:tt)* ) -> ($e:ident, $($v:ident),+)) => {
+        $crate::arg_enum!(@as_item
+        $($tts)*
+
+        impl ::std::str::FromStr for $e {
+            type Err = String;
+
+            fn from_str(s: &str) -> ::std::result::Result<Self,Self::Err> {
+                #[allow(deprecated, unused_imports)]
+                use ::std::ascii::AsciiExt;
+                match s {
+                    $(stringify!($v) |
+                    _ if s.eq_ignore_ascii_case(stringify!($v)) => Ok($e::$v)),+,
+                    _ => Err({
+                        let v = vec![
+                            $(stringify!($v),)+
+                        ];
+                        format!("valid values: {}",
+                            v.join(", "))
+                    }),
+                }
+            }
+        }
+        impl ::std::fmt::Display for $e {
+            fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
+                match *self {
+                    $($e::$v => write!(f, stringify!($v)),)+
+                }
+            }
+        }
+        impl $e {
+            #[allow(dead_code)]
+            pub fn variants() -> [&'static str; $crate::_clap_count_exprs!($(stringify!($v)),+)] {
+                [
+                    $(stringify!($v),)+
+                ]
+            }
+        });
+    };
+    ($(#[$($m:meta),+])+ pub enum $e:ident { $($v:ident $(=$val:expr)*,)+ } ) => {
+        $crate::arg_enum!(@impls
+            ($(#[$($m),+])+
+            pub enum $e {
+                $($v$(=$val)*),+
+            }) -> ($e, $($v),+)
+        );
+    };
+    ($(#[$($m:meta),+])+ pub enum $e:ident { $($v:ident $(=$val:expr)*),+ } ) => {
+        $crate::arg_enum!(@impls
+            ($(#[$($m),+])+
+            pub enum $e {
+                $($v$(=$val)*),+
+            }) -> ($e, $($v),+)
+        );
+    };
+    ($(#[$($m:meta),+])+ enum $e:ident { $($v:ident $(=$val:expr)*,)+ } ) => {
+        $crate::arg_enum!(@impls
+            ($(#[$($m),+])+
+             enum $e {
+                 $($v$(=$val)*),+
+             }) -> ($e, $($v),+)
+        );
+    };
+    ($(#[$($m:meta),+])+ enum $e:ident { $($v:ident $(=$val:expr)*),+ } ) => {
+        $crate::arg_enum!(@impls
+            ($(#[$($m),+])+
+            enum $e {
+                $($v$(=$val)*),+
+            }) -> ($e, $($v),+)
+        );
+    };
+    (pub enum $e:ident { $($v:ident $(=$val:expr)*,)+ } ) => {
+        $crate::arg_enum!(@impls
+            (pub enum $e {
+                $($v$(=$val)*),+
+            }) -> ($e, $($v),+)
+        );
+    };
+    (pub enum $e:ident { $($v:ident $(=$val:expr)*),+ } ) => {
+        $crate::arg_enum!(@impls
+            (pub enum $e {
+                $($v$(=$val)*),+
+            }) -> ($e, $($v),+)
+        );
+    };
+    (enum $e:ident { $($v:ident $(=$val:expr)*,)+ } ) => {
+        $crate::arg_enum!(@impls
+            (enum $e {
+                $($v$(=$val)*),+
+            }) -> ($e, $($v),+)
+        );
+    };
+    (enum $e:ident { $($v:ident $(=$val:expr)*),+ } ) => {
+        $crate::arg_enum!(@impls
+            (enum $e {
+                $($v$(=$val)*),+
+            }) -> ($e, $($v),+)
+        );
+    };
+}
+
+/// Allows you to pull the version from your Cargo.toml at compile time as
+/// `MAJOR.MINOR.PATCH_PKGVERSION_PRE`
+///
+/// # Examples
+///
+/// ```no_run
+/// # #[macro_use]
+/// # extern crate clap;
+/// # use clap::Command;
+/// # fn main() {
+/// let m = Command::new("cmd")
+///             .version(crate_version!())
+///             .get_matches();
+/// # }
+/// ```
+#[cfg(feature = "cargo")]
+#[macro_export]
+macro_rules! crate_version {
+    () => {
+        env!("CARGO_PKG_VERSION")
+    };
+}
+
+/// Allows you to pull the authors for the command from your Cargo.toml at
+/// compile time in the form:
+/// `"author1 lastname <author1@example.com>:author2 lastname <author2@example.com>"`
+///
+/// You can replace the colons with a custom separator by supplying a
+/// replacement string, so, for example,
+/// `crate_authors!(",\n")` would become
+/// `"author1 lastname <author1@example.com>,\nauthor2 lastname <author2@example.com>,\nauthor3 lastname <author3@example.com>"`
+///
+/// # Examples
+///
+/// ```no_run
+/// # #[macro_use]
+/// # extern crate clap;
+/// # use clap::Command;
+/// # fn main() {
+/// let m = Command::new("cmd")
+///             .author(crate_authors!("\n"))
+///             .get_matches();
+/// # }
+/// ```
+#[cfg(feature = "cargo")]
+#[macro_export]
+macro_rules! crate_authors {
+    ($sep:expr) => {{
+        static CACHED: clap::__macro_refs::once_cell::sync::Lazy<String> =
+            clap::__macro_refs::once_cell::sync::Lazy::new(|| {
+                env!("CARGO_PKG_AUTHORS").replace(':', $sep)
+            });
+
+        let s: &'static str = &*CACHED;
+        s
+    }};
+    () => {
+        env!("CARGO_PKG_AUTHORS")
+    };
+}
+
+/// Allows you to pull the description from your Cargo.toml at compile time.
+///
+/// # Examples
+///
+/// ```no_run
+/// # #[macro_use]
+/// # extern crate clap;
+/// # use clap::Command;
+/// # fn main() {
+/// let m = Command::new("cmd")
+///             .about(crate_description!())
+///             .get_matches();
+/// # }
+/// ```
+#[cfg(feature = "cargo")]
+#[macro_export]
+macro_rules! crate_description {
+    () => {
+        env!("CARGO_PKG_DESCRIPTION")
+    };
+}
+
+/// Allows you to pull the name from your Cargo.toml at compile time.
+///
+/// # Examples
+///
+/// ```no_run
+/// # #[macro_use]
+/// # extern crate clap;
+/// # use clap::Command;
+/// # fn main() {
+/// let m = Command::new(crate_name!())
+///             .get_matches();
+/// # }
+/// ```
+#[cfg(feature = "cargo")]
+#[macro_export]
+macro_rules! crate_name {
+    () => {
+        env!("CARGO_PKG_NAME")
+    };
+}
+
+/// Allows you to build the `Command` instance from your Cargo.toml at compile time.
+///
+/// **NOTE:** Changing the values in your `Cargo.toml` does not trigger a re-build automatically,
+/// and therefore won't change the generated output until you recompile.
+///
+/// In some cases you can "trick" the compiler into triggering a rebuild when your
+/// `Cargo.toml` is changed by including this in your `src/main.rs` file
+/// `include_str!("../Cargo.toml");`
+///
+/// # Examples
+///
+/// ```no_run
+/// # #[macro_use]
+/// # extern crate clap;
+/// # fn main() {
+/// let m = command!().get_matches();
+/// # }
+/// ```
+#[cfg(feature = "cargo")]
+#[macro_export]
+macro_rules! command {
+    () => {{
+        $crate::command!($crate::crate_name!())
+    }};
+    ($name:expr) => {{
+        let mut cmd = $crate::Command::new($name).version($crate::crate_version!());
+
+        let author = $crate::crate_authors!();
+        if !author.is_empty() {
+            cmd = cmd.author(author)
+        }
+
+        let about = $crate::crate_description!();
+        if !about.is_empty() {
+            cmd = cmd.about(about)
+        }
+
+        cmd
+    }};
+}
+
+/// Requires `cargo` feature flag to be enabled.
+#[cfg(not(feature = "cargo"))]
+#[macro_export]
+macro_rules! command {
+    () => {{
+        compile_error!("`cargo` feature flag is required");
+    }};
+    ($name:expr) => {{
+        compile_error!("`cargo` feature flag is required");
+    }};
+}
+
+/// Deprecated, replaced with [`clap::command!`][crate::command]
+#[cfg(feature = "cargo")]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.1.0", note = "Replaced with `clap::command!")
+)]
+#[macro_export]
+macro_rules! app_from_crate {
+    () => {{
+        let mut cmd = $crate::Command::new($crate::crate_name!()).version($crate::crate_version!());
+
+        let author = $crate::crate_authors!(", ");
+        if !author.is_empty() {
+            cmd = cmd.author(author)
+        }
+
+        let about = $crate::crate_description!();
+        if !about.is_empty() {
+            cmd = cmd.about(about)
+        }
+
+        cmd
+    }};
+    ($sep:expr) => {{
+        let mut cmd = $crate::Command::new($crate::crate_name!()).version($crate::crate_version!());
+
+        let author = $crate::crate_authors!($sep);
+        if !author.is_empty() {
+            cmd = cmd.author(author)
+        }
+
+        let about = $crate::crate_description!();
+        if !about.is_empty() {
+            cmd = cmd.about(about)
+        }
+
+        cmd
+    }};
+}
+
+#[doc(hidden)]
+#[macro_export]
+macro_rules! arg_impl {
+    ( @string $val:ident ) => {
+        stringify!($val)
+    };
+    ( @string $val:literal ) => {{
+        let ident_or_string_literal: &str = $val;
+        ident_or_string_literal
+    }};
+    ( @string $val:tt ) => {
+        ::std::compile_error!("Only identifiers or string literals supported");
+    };
+    ( @string ) => {
+        None
+    };
+
+    ( @char $val:ident ) => {{
+        let ident_or_char_literal = stringify!($val);
+        debug_assert_eq!(
+            ident_or_char_literal.len(),
+            1,
+            "Single-letter identifier expected, got {}",
+            ident_or_char_literal
+        );
+        ident_or_char_literal.chars().next().unwrap()
+    }};
+    ( @char $val:literal ) => {{
+        let ident_or_char_literal: char = $val;
+        ident_or_char_literal
+    }};
+    ( @char ) => {{
+        None
+    }};
+
+    (
+        @arg
+        ($arg:expr)
+        --$long:ident
+        $($tail:tt)*
+    ) => {
+        $crate::arg_impl! {
+            @arg
+            ({
+                debug_assert_eq!($arg.get_value_names(), None, "Flags should precede values");
+                #[allow(deprecated)]
+                {
+                    debug_assert!(!$arg.is_multiple_occurrences_set(), "Flags should precede `...`");
+                }
+
+                let mut arg = $arg;
+                let long = $crate::arg_impl! { @string $long };
+                if arg.get_id().is_empty() {
+                    arg = arg.id(long);
+                }
+                arg.long(long)
+            })
+            $($tail)*
+        }
+    };
+    (
+        @arg
+        ($arg:expr)
+        --$long:literal
+        $($tail:tt)*
+    ) => {
+        $crate::arg_impl! {
+            @arg
+            ({
+                debug_assert_eq!($arg.get_value_names(), None, "Flags should precede values");
+                #[allow(deprecated)]
+                {
+                    debug_assert!(!$arg.is_multiple_occurrences_set(), "Flags should precede `...`");
+                }
+
+                let mut arg = $arg;
+                let long = $crate::arg_impl! { @string $long };
+                if arg.get_id().is_empty() {
+                    arg = arg.id(long);
+                }
+                arg.long(long)
+            })
+            $($tail)*
+        }
+    };
+    (
+        @arg
+        ($arg:expr)
+        -$short:ident
+        $($tail:tt)*
+    ) => {
+        $crate::arg_impl! {
+            @arg
+            ({
+                debug_assert_eq!($arg.get_long(), None, "Short flags should precede long flags");
+                debug_assert_eq!($arg.get_value_names(), None, "Flags should precede values");
+                #[allow(deprecated)]
+                {
+                    debug_assert!(!$arg.is_multiple_occurrences_set(), "Flags should precede `...`");
+                }
+
+                $arg.short($crate::arg_impl! { @char $short })
+            })
+            $($tail)*
+        }
+    };
+    (
+        @arg
+        ($arg:expr)
+        -$short:literal
+        $($tail:tt)*
+    ) => {
+        $crate::arg_impl! {
+            @arg
+            ({
+                debug_assert_eq!($arg.get_long(), None, "Short flags should precede long flags");
+                debug_assert_eq!($arg.get_value_names(), None, "Flags should precede values");
+                #[allow(deprecated)]
+                {
+                    debug_assert!(!$arg.is_multiple_occurrences_set(), "Flags should precede `...`");
+                }
+
+                $arg.short($crate::arg_impl! { @char $short })
+            })
+            $($tail)*
+        }
+    };
+    (
+        @arg
+        ($arg:expr)
+        <$value_name:ident>
+        $($tail:tt)*
+    ) => {
+        $crate::arg_impl! {
+            @arg
+            ({
+                #[allow(deprecated)]
+                {
+                    debug_assert!(!$arg.is_multiple_occurrences_set(), "Values should precede `...`");
+                }
+                debug_assert_eq!($arg.get_value_names(), None, "Multiple values not yet supported");
+
+                let mut arg = $arg;
+
+                arg = arg.required(true);
+                arg = arg.takes_value(true);
+
+                let value_name = $crate::arg_impl! { @string $value_name };
+                if arg.get_id().is_empty() {
+                    arg = arg.id(value_name);
+                }
+                arg.value_name(value_name)
+            })
+            $($tail)*
+        }
+    };
+    (
+        @arg
+        ($arg:expr)
+        <$value_name:literal>
+        $($tail:tt)*
+    ) => {
+        $crate::arg_impl! {
+            @arg
+            ({
+                #[allow(deprecated)]
+                {
+                    debug_assert!(!$arg.is_multiple_occurrences_set(), "Values should precede `...`");
+                }
+                debug_assert_eq!($arg.get_value_names(), None, "Multiple values not yet supported");
+
+                let mut arg = $arg;
+
+                arg = arg.required(true);
+                arg = arg.takes_value(true);
+
+                let value_name = $crate::arg_impl! { @string $value_name };
+                if arg.get_id().is_empty() {
+                    arg = arg.id(value_name);
+                }
+                arg.value_name(value_name)
+            })
+            $($tail)*
+        }
+    };
+    (
+        @arg
+        ($arg:expr)
+        [$value_name:ident]
+        $($tail:tt)*
+    ) => {
+        $crate::arg_impl! {
+            @arg
+            ({
+                #[allow(deprecated)]
+                {
+                    debug_assert!(!$arg.is_multiple_occurrences_set(), "Values should precede `...`");
+                }
+                debug_assert_eq!($arg.get_value_names(), None, "Multiple values not yet supported");
+
+                let mut arg = $arg;
+
+                if arg.get_long().is_none() && arg.get_short().is_none() {
+                    arg = arg.required(false);
+                } else {
+                    arg = arg.min_values(0).max_values(1);
+                }
+                arg = arg.takes_value(true);
+
+                let value_name = $crate::arg_impl! { @string $value_name };
+                if arg.get_id().is_empty() {
+                    arg = arg.id(value_name);
+                }
+                arg.value_name(value_name)
+            })
+            $($tail)*
+        }
+    };
+    (
+        @arg
+        ($arg:expr)
+        [$value_name:literal]
+        $($tail:tt)*
+    ) => {
+        $crate::arg_impl! {
+            @arg
+            ({
+                #[allow(deprecated)]
+                {
+                    debug_assert!(!$arg.is_multiple_occurrences_set(), "Values should precede `...`");
+                }
+                debug_assert_eq!($arg.get_value_names(), None, "Multiple values not yet supported");
+
+                let mut arg = $arg;
+
+                if arg.get_long().is_none() && arg.get_short().is_none() {
+                    arg = arg.required(false);
+                } else {
+                    arg = arg.min_values(0).max_values(1);
+                }
+                arg = arg.takes_value(true);
+
+                let value_name = $crate::arg_impl! { @string $value_name };
+                if arg.get_id().is_empty() {
+                    arg = arg.id(value_name);
+                }
+                arg.value_name(value_name)
+            })
+            $($tail)*
+        }
+    };
+    (
+        @arg
+        ($arg:expr)
+        ...
+        $($tail:tt)*
+    ) => {
+        $crate::arg_impl! {
+            @arg
+            ({#[allow(deprecated)]{
+                $arg.multiple_occurrences(true)
+            }})
+            $($tail)*
+        }
+    };
+    (
+        @arg
+        ($arg:expr)
+        $help:literal
+    ) => {
+        $arg.help($help)
+    };
+    (
+        @arg
+        ($arg:expr)
+    ) => {
+        $arg
+    };
+}
+
+/// Create an [`Arg`] from a usage string.
+///
+/// Allows creation of basic settings for the [`Arg`].
+///
+/// **NOTE**: Not all settings may be set using the usage string method. Some properties are
+/// only available via the builder pattern.
+///
+/// # Syntax
+///
+/// Usage strings typically following the form:
+///
+/// ```notrust
+/// [explicit name] [short] [long] [value names] [...] [help string]
+/// ```
+///
+/// ### Explicit Name
+///
+/// The name may be either a bare-word or a string, followed by a `:`, like `name:` or
+/// `"name":`.
+///
+/// *Note:* This is an optional field, if it's omitted the argument will use one of the additional
+/// fields as the name using the following priority order:
+///
+///  1. Explicit Name
+///  2. Long
+///  3. Value Name
+///
+/// See [`Arg::name`][crate::Arg::name].
+///
+/// ### Short
+///
+/// A short flag is a `-` followed by either a bare-character or quoted character, like `-f` or
+/// `-'f'`.
+///
+/// See [`Arg::short`][crate::Arg::short].
+///
+/// ### Long
+///
+/// A long flag is a `--` followed by either a bare-word or a string, like `--foo` or
+/// `--"foo"`.
+///
+/// See [`Arg::long`][crate::Arg::long].
+///
+/// ### Values (Value Notation)
+///
+/// This is set by placing bare-word between:
+/// - `[]` like `[FOO]`
+///   - Positional argument: optional
+///   - Named argument: optional value
+/// - `<>` like `<FOO>`: required
+///
+/// See [`Arg::value_name`][crate::Arg::value_name].
+///
+/// ### `...`
+///
+/// `...` (three consecutive dots/periods) specifies that this argument may occur multiple
+/// times (not to be confused with multiple values per occurrence).
+///
+/// See [`Arg::multiple_occurrences`][crate::Arg::multiple_occurrences].
+///
+/// ### Help String
+///
+/// The help string is denoted between a pair of double quotes `""` and may contain any
+/// characters.
+///
+/// # Examples
+///
+/// ```rust
+/// # use clap::{Command, Arg, arg};
+/// Command::new("prog")
+///     .args(&[
+///         arg!(--config <FILE> "a required file for the configuration and no short"),
+///         arg!(-d --debug ... "turns on debugging information and allows multiples"),
+///         arg!([input] "an optional input file to use")
+/// ])
+/// # ;
+/// ```
+/// [`Arg`]: ./struct.Arg.html
+#[macro_export]
+macro_rules! arg {
+    ( $name:ident: $($tail:tt)+ ) => {
+        $crate::arg_impl! {
+            @arg ($crate::Arg::new($crate::arg_impl! { @string $name })) $($tail)+
+        }
+    };
+    ( $($tail:tt)+ ) => {{
+        let arg = $crate::arg_impl! {
+            @arg ($crate::Arg::default()) $($tail)+
+        };
+        debug_assert!(!arg.get_id().is_empty(), "Without a value or long flag, the `name:` prefix is required");
+        arg
+    }};
+}
+
+/// Deprecated, replaced with [`clap::Parser`][crate::Parser] and [`clap::arg!`][crate::arg] (Issue clap-rs/clap#2835)
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(
+        since = "3.0.0",
+        note = "Replaced with `clap::Parser` for a declarative API (Issue clap-rs/clap#2835)"
+    )
+)]
+#[doc(hidden)]
+#[macro_export]
+macro_rules! clap_app {
+    (@app ($builder:expr)) => { $builder };
+    (@app ($builder:expr) (@arg ($name:expr): $($tail:tt)*) $($tt:tt)*) => {
+        $crate::clap_app!{ @app
+            ($builder.arg(
+                $crate::clap_app!{ @arg ($crate::Arg::new($name)) (-) $($tail)* }))
+            $($tt)*
+        }
+    };
+    (@app ($builder:expr) (@arg $name:ident: $($tail:tt)*) $($tt:tt)*) => {
+        $crate::clap_app!{ @app
+            ($builder.arg(
+                $crate::clap_app!{ @arg ($crate::Arg::new(stringify!($name))) (-) $($tail)* }))
+            $($tt)*
+        }
+    };
+    (@app ($builder:expr) (@setting $setting:ident) $($tt:tt)*) => {
+        $crate::clap_app!{ @app
+            ($builder.setting($crate::AppSettings::$setting))
+            $($tt)*
+        }
+    };
+// Treat the application builder as an argument to set its attributes
+    (@app ($builder:expr) (@attributes $($attr:tt)*) $($tt:tt)*) => {
+        $crate::clap_app!{ @app ($crate::clap_app!{ @arg ($builder) $($attr)* }) $($tt)* }
+    };
+    (@app ($builder:expr) (@group $name:ident => $($tail:tt)*) $($tt:tt)*) => {
+        $crate::clap_app!{ @app
+            ($crate::clap_app!{ @group ($builder, $crate::ArgGroup::new(stringify!($name))) $($tail)* })
+            $($tt)*
+        }
+    };
+    (@app ($builder:expr) (@group $name:ident !$ident:ident => $($tail:tt)*) $($tt:tt)*) => {
+        $crate::clap_app!{ @app
+            ($crate::clap_app!{ @group ($builder, $crate::ArgGroup::new(stringify!($name)).$ident(false)) $($tail)* })
+            $($tt)*
+        }
+    };
+    (@app ($builder:expr) (@group $name:ident +$ident:ident => $($tail:tt)*) $($tt:tt)*) => {
+        $crate::clap_app!{ @app
+            ($crate::clap_app!{ @group ($builder, $crate::ArgGroup::new(stringify!($name)).$ident(true)) $($tail)* })
+            $($tt)*
+        }
+    };
+// Handle subcommand creation
+    (@app ($builder:expr) (@subcommand $name:ident => $($tail:tt)*) $($tt:tt)*) => {
+        $crate::clap_app!{ @app
+            ($builder.subcommand(
+                $crate::clap_app!{ @app ($crate::Command::new(stringify!($name))) $($tail)* }
+            ))
+            $($tt)*
+        }
+    };
+// Yaml like function calls - used for setting various meta directly against the app
+    (@app ($builder:expr) ($ident:ident: $($v:expr),*) $($tt:tt)*) => {
+// $crate::clap_app!{ @app ($builder.$ident($($v),*)) $($tt)* }
+        $crate::clap_app!{ @app
+            ($builder.$ident($($v),*))
+            $($tt)*
+        }
+    };
+
+// Add members to group and continue argument handling with the parent builder
+    (@group ($builder:expr, $group:expr)) => { $builder.group($group) };
+    // Treat the group builder as an argument to set its attributes
+    (@group ($builder:expr, $group:expr) (@attributes $($attr:tt)*) $($tt:tt)*) => {
+        $crate::clap_app!{ @group ($builder, $crate::clap_app!{ @arg ($group) (-) $($attr)* }) $($tt)* }
+    };
+    (@group ($builder:expr, $group:expr) (@arg $name:ident: $($tail:tt)*) $($tt:tt)*) => {
+        $crate::clap_app!{ @group
+            ($crate::clap_app!{ @app ($builder) (@arg $name: $($tail)*) },
+             $group.arg(stringify!($name)))
+            $($tt)*
+        }
+    };
+
+// No more tokens to munch
+    (@arg ($arg:expr) $modes:tt) => { $arg };
+// Shorthand tokens influenced by the usage_string
+    (@arg ($arg:expr) $modes:tt --($long:expr) $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.long($long)) $modes $($tail)* }
+    };
+    (@arg ($arg:expr) $modes:tt --$long:ident $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.long(stringify!($long))) $modes $($tail)* }
+    };
+    (@arg ($arg:expr) $modes:tt -$short:ident $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.short(stringify!($short).chars().next().unwrap())) $modes $($tail)* }
+    };
+    (@arg ($arg:expr) (-) <$var:ident> $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.value_name(stringify!($var))) (+) +takes_value +required $($tail)* }
+    };
+    (@arg ($arg:expr) (+) <$var:ident> $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.value_name(stringify!($var))) (+) $($tail)* }
+    };
+    (@arg ($arg:expr) (-) [$var:ident] $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.value_name(stringify!($var))) (+) +takes_value $($tail)* }
+    };
+    (@arg ($arg:expr) (+) [$var:ident] $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.value_name(stringify!($var))) (+) $($tail)* }
+    };
+    (@arg ($arg:expr) $modes:tt ... $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg) $modes +multiple +takes_value $($tail)* }
+    };
+// Shorthand magic
+    (@arg ($arg:expr) $modes:tt #{$n:expr, $m:expr} $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg) $modes min_values($n) max_values($m) $($tail)* }
+    };
+    (@arg ($arg:expr) $modes:tt * $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg) $modes +required $($tail)* }
+    };
+// !foo -> .foo(false)
+    (@arg ($arg:expr) $modes:tt !$ident:ident $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.$ident(false)) $modes $($tail)* }
+    };
+// +foo -> .foo(true)
+    (@arg ($arg:expr) $modes:tt +$ident:ident $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.$ident(true)) $modes $($tail)* }
+    };
+// Validator
+    (@arg ($arg:expr) $modes:tt {$fn_:expr} $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.validator($fn_)) $modes $($tail)* }
+    };
+    (@as_expr $expr:expr) => { $expr };
+// Help
+    (@arg ($arg:expr) $modes:tt $desc:tt) => { $arg.help($crate::clap_app!{ @as_expr $desc }) };
+// Handle functions that need to be called multiple times for each argument
+    (@arg ($arg:expr) $modes:tt $ident:ident[$($target:ident)*] $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg $( .$ident(stringify!($target)) )*) $modes $($tail)* }
+    };
+// Inherit builder's functions, e.g. `index(2)`, `requires_if("val", "arg")`
+    (@arg ($arg:expr) $modes:tt $ident:ident($($expr:expr),*) $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.$ident($($expr),*)) $modes $($tail)* }
+    };
+// Inherit builder's functions with trailing comma, e.g. `index(2,)`, `requires_if("val", "arg",)`
+    (@arg ($arg:expr) $modes:tt $ident:ident($($expr:expr,)*) $($tail:tt)*) => {
+        $crate::clap_app!{ @arg ($arg.$ident($($expr),*)) $modes $($tail)* }
+    };
+
+// Build a subcommand outside of an app.
+    (@subcommand $name:ident => $($tail:tt)*) => {
+        $crate::clap_app!{ @app ($crate::Command::new(stringify!($name))) $($tail)* }
+    };
+// Start the magic
+    (($name:expr) => $($tail:tt)*) => {{
+        $crate::clap_app!{ @app ($crate::Command::new($name)) $($tail)*}
+    }};
+
+    ($name:ident => $($tail:tt)*) => {{
+        $crate::clap_app!{ @app ($crate::Command::new(stringify!($name))) $($tail)*}
+    }};
+}
+
+macro_rules! impl_settings {
+    ($settings:ident, $flags:ident,
+        $(
+            $(#[$inner:ident $($args:tt)*])*
+            $setting:ident => $flag:path
+        ),+
+    ) => {
+        impl $flags {
+            #[allow(dead_code)]
+            pub(crate) fn empty() -> Self {
+                $flags(Flags::empty())
+            }
+
+            #[allow(dead_code)]
+            pub(crate) fn insert(&mut self, rhs: Self) {
+                self.0.insert(rhs.0);
+            }
+
+            #[allow(dead_code)]
+            pub(crate) fn remove(&mut self, rhs: Self) {
+                self.0.remove(rhs.0);
+            }
+
+            #[allow(dead_code)]
+            pub(crate) fn set(&mut self, s: $settings) {
+                #[allow(deprecated)]  // some Settings might be deprecated
+                match s {
+                    $(
+                        $(#[$inner $($args)*])*
+                        $settings::$setting => self.0.insert($flag),
+                    )*
+                }
+            }
+
+            #[allow(dead_code)]
+            pub(crate) fn unset(&mut self, s: $settings) {
+                #[allow(deprecated)]  // some Settings might be deprecated
+                match s {
+                    $(
+                        $(#[$inner $($args)*])*
+                        $settings::$setting => self.0.remove($flag),
+                    )*
+                }
+            }
+
+            #[allow(dead_code)]
+            pub(crate) fn is_set(&self, s: $settings) -> bool {
+                #[allow(deprecated)]  // some Settings might be deprecated
+                match s {
+                    $(
+                        $(#[$inner $($args)*])*
+                        $settings::$setting => self.0.contains($flag),
+                    )*
+                }
+            }
+        }
+
+        impl BitOr for $flags {
+            type Output = Self;
+
+            fn bitor(mut self, rhs: Self) -> Self::Output {
+                self.0.insert(rhs.0);
+                self
+            }
+        }
+
+        impl From<$settings> for $flags {
+            fn from(setting: $settings) -> Self {
+                let mut flags = $flags::empty();
+                flags.set(setting);
+                flags
+            }
+        }
+
+        impl BitOr<$settings> for $flags {
+            type Output = Self;
+
+            fn bitor(mut self, rhs: $settings) -> Self::Output {
+                self.set(rhs);
+                self
+            }
+        }
+
+        impl BitOr for $settings {
+            type Output = $flags;
+
+            fn bitor(self, rhs: Self) -> Self::Output {
+                let mut flags = $flags::empty();
+                flags.set(self);
+                flags.set(rhs);
+                flags
+            }
+        }
+    }
+}
+
+// Convenience for writing to stderr thanks to https://github.com/BurntSushi
+macro_rules! wlnerr {
+    ($($arg:tt)*) => ({
+        use std::io::{Write, stderr};
+        writeln!(&mut stderr(), $($arg)*).ok();
+    })
+}
+
+#[cfg(feature = "debug")]
+macro_rules! debug {
+    ($($arg:tt)*) => ({
+        let prefix = format!("[{:>w$}] \t", module_path!(), w = 28);
+        let body = format!($($arg)*);
+        let mut color = $crate::output::fmt::Colorizer::new($crate::output::fmt::Stream::Stderr, $crate::ColorChoice::Auto);
+        color.hint(prefix);
+        color.hint(body);
+        color.none("\n");
+        let _ = color.print();
+    })
+}
+
+#[cfg(not(feature = "debug"))]
+macro_rules! debug {
+    ($($arg:tt)*) => {};
+}
diff --git a/vendor/clap-3.2.20/src/mkeymap.rs b/vendor/clap-3.2.20/src/mkeymap.rs
new file mode 100644
index 000000000..97ecdda77
--- /dev/null
+++ b/vendor/clap-3.2.20/src/mkeymap.rs
@@ -0,0 +1,193 @@
+use std::iter::Iterator;
+use std::ops::Index;
+use std::{ffi::OsStr, ffi::OsString};
+
+use crate::util::Id;
+use crate::Arg;
+use crate::INTERNAL_ERROR_MSG;
+
+#[derive(PartialEq, Eq, Debug, Clone)]
+pub(crate) struct Key {
+    key: KeyType,
+    index: usize,
+}
+
+#[derive(Default, PartialEq, Eq, Debug, Clone)]
+pub(crate) struct MKeyMap<'help> {
+    /// All of the arguments.
+    args: Vec<Arg<'help>>,
+
+    // Cache part:
+    /// Will be set after `_build()`.
+    keys: Vec<Key>,
+}
+
+#[derive(Debug, PartialEq, Eq, Hash, Clone)]
+pub(crate) enum KeyType {
+    Short(char),
+    Long(OsString),
+    Position(usize),
+}
+
+impl KeyType {
+    pub(crate) fn is_position(&self) -> bool {
+        matches!(self, KeyType::Position(_))
+    }
+}
+
+impl PartialEq<usize> for KeyType {
+    fn eq(&self, rhs: &usize) -> bool {
+        match self {
+            KeyType::Position(x) => x == rhs,
+            _ => false,
+        }
+    }
+}
+
+impl PartialEq<&str> for KeyType {
+    fn eq(&self, rhs: &&str) -> bool {
+        match self {
+            KeyType::Long(l) => l == rhs,
+            _ => false,
+        }
+    }
+}
+
+impl PartialEq<str> for KeyType {
+    fn eq(&self, rhs: &str) -> bool {
+        match self {
+            KeyType::Long(l) => l == rhs,
+            _ => false,
+        }
+    }
+}
+
+impl PartialEq<OsStr> for KeyType {
+    fn eq(&self, rhs: &OsStr) -> bool {
+        match self {
+            KeyType::Long(l) => l == rhs,
+            _ => false,
+        }
+    }
+}
+
+impl PartialEq<char> for KeyType {
+    fn eq(&self, rhs: &char) -> bool {
+        match self {
+            KeyType::Short(c) => c == rhs,
+            _ => false,
+        }
+    }
+}
+
+impl<'help> MKeyMap<'help> {
+    /// If any arg has corresponding key in this map, we can search the key with
+    /// u64(for positional argument), char(for short flag), &str and OsString
+    /// (for long flag)
+    pub(crate) fn contains<K>(&self, key: K) -> bool
+    where
+        KeyType: PartialEq<K>,
+    {
+        self.keys.iter().any(|x| x.key == key)
+    }
+
+    /// Reserves capacity for at least additional more elements to be inserted
+    pub(crate) fn reserve(&mut self, additional: usize) {
+        self.args.reserve(additional);
+    }
+
+    /// Push an argument in the map.
+    pub(crate) fn push(&mut self, new_arg: Arg<'help>) {
+        self.args.push(new_arg);
+    }
+
+    /// Find the arg have corresponding key in this map, we can search the key
+    /// with u64(for positional argument), char(for short flag), &str and
+    /// OsString (for long flag)
+    pub(crate) fn get<K: ?Sized>(&self, key: &K) -> Option<&Arg<'help>>
+    where
+        KeyType: PartialEq<K>,
+    {
+        self.keys
+            .iter()
+            .find(|k| &k.key == key)
+            .map(|k| &self.args[k.index])
+    }
+
+    /// Find out if the map have no arg.
+    pub(crate) fn is_empty(&self) -> bool {
+        self.args.is_empty()
+    }
+
+    /// Return iterators of all keys.
+    pub(crate) fn keys(&self) -> impl Iterator<Item = &KeyType> {
+        self.keys.iter().map(|x| &x.key)
+    }
+
+    /// Return iterators of all args.
+    pub(crate) fn args(&self) -> impl Iterator<Item = &Arg<'help>> {
+        self.args.iter()
+    }
+
+    /// Return mutable iterators of all args.
+    pub(crate) fn args_mut<'map>(&'map mut self) -> impl Iterator<Item = &'map mut Arg<'help>> {
+        self.args.iter_mut()
+    }
+
+    /// We need a lazy build here since some we may change args after creating
+    /// the map, you can checkout who uses `args_mut`.
+    pub(crate) fn _build(&mut self) {
+        for (i, arg) in self.args.iter().enumerate() {
+            append_keys(&mut self.keys, arg, i);
+        }
+    }
+
+    /// Remove an arg in the graph by Id, usually used by `mut_arg`. Return
+    /// `Some(arg)` if removed.
+    pub(crate) fn remove_by_name(&mut self, name: &Id) -> Option<Arg<'help>> {
+        self.args
+            .iter()
+            .position(|arg| &arg.id == name)
+            // since it's a cold function, using this wouldn't hurt much
+            .map(|i| self.args.remove(i))
+    }
+
+    /// Remove an arg based on index
+    pub(crate) fn remove(&mut self, index: usize) -> Arg<'help> {
+        self.args.remove(index)
+    }
+}
+
+impl<'help> Index<&'_ KeyType> for MKeyMap<'help> {
+    type Output = Arg<'help>;
+
+    fn index(&self, key: &KeyType) -> &Self::Output {
+        self.get(key).expect(INTERNAL_ERROR_MSG)
+    }
+}
+
+/// Generate key types for an specific Arg.
+fn append_keys(keys: &mut Vec<Key>, arg: &Arg, index: usize) {
+    if let Some(pos_index) = arg.index {
+        let key = KeyType::Position(pos_index);
+        keys.push(Key { key, index });
+    } else {
+        if let Some(short) = arg.short {
+            let key = KeyType::Short(short);
+            keys.push(Key { key, index });
+        }
+        if let Some(long) = arg.long {
+            let key = KeyType::Long(OsString::from(long));
+            keys.push(Key { key, index });
+        }
+
+        for (short, _) in arg.short_aliases.iter() {
+            let key = KeyType::Short(*short);
+            keys.push(Key { key, index });
+        }
+        for (long, _) in arg.aliases.iter() {
+            let key = KeyType::Long(OsString::from(long));
+            keys.push(Key { key, index });
+        }
+    }
+}
diff --git a/vendor/clap-3.2.20/src/output/fmt.rs b/vendor/clap-3.2.20/src/output/fmt.rs
new file mode 100644
index 000000000..dc1f46e08
--- /dev/null
+++ b/vendor/clap-3.2.20/src/output/fmt.rs
@@ -0,0 +1,158 @@
+use crate::util::color::ColorChoice;
+
+use std::{
+    fmt::{self, Display, Formatter},
+    io::{self, Write},
+};
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub(crate) enum Stream {
+    Stdout,
+    Stderr,
+}
+
+#[derive(Clone, Debug)]
+pub(crate) struct Colorizer {
+    stream: Stream,
+    #[allow(unused)]
+    color_when: ColorChoice,
+    pieces: Vec<(String, Style)>,
+}
+
+impl Colorizer {
+    #[inline(never)]
+    pub(crate) fn new(stream: Stream, color_when: ColorChoice) -> Self {
+        Colorizer {
+            stream,
+            color_when,
+            pieces: vec![],
+        }
+    }
+
+    #[inline(never)]
+    pub(crate) fn good(&mut self, msg: impl Into<String>) {
+        self.pieces.push((msg.into(), Style::Good));
+    }
+
+    #[inline(never)]
+    pub(crate) fn warning(&mut self, msg: impl Into<String>) {
+        self.pieces.push((msg.into(), Style::Warning));
+    }
+
+    #[inline(never)]
+    pub(crate) fn error(&mut self, msg: impl Into<String>) {
+        self.pieces.push((msg.into(), Style::Error));
+    }
+
+    #[inline(never)]
+    #[allow(dead_code)]
+    pub(crate) fn hint(&mut self, msg: impl Into<String>) {
+        self.pieces.push((msg.into(), Style::Hint));
+    }
+
+    #[inline(never)]
+    pub(crate) fn none(&mut self, msg: impl Into<String>) {
+        self.pieces.push((msg.into(), Style::Default));
+    }
+}
+
+/// Printing methods.
+impl Colorizer {
+    #[cfg(feature = "color")]
+    pub(crate) fn print(&self) -> io::Result<()> {
+        use termcolor::{BufferWriter, ColorChoice as DepColorChoice, ColorSpec, WriteColor};
+
+        let color_when = match self.color_when {
+            ColorChoice::Always => DepColorChoice::Always,
+            ColorChoice::Auto if is_a_tty(self.stream) => DepColorChoice::Auto,
+            _ => DepColorChoice::Never,
+        };
+
+        let writer = match self.stream {
+            Stream::Stderr => BufferWriter::stderr(color_when),
+            Stream::Stdout => BufferWriter::stdout(color_when),
+        };
+
+        let mut buffer = writer.buffer();
+
+        for piece in &self.pieces {
+            let mut color = ColorSpec::new();
+            match piece.1 {
+                Style::Good => {
+                    color.set_fg(Some(termcolor::Color::Green));
+                }
+                Style::Warning => {
+                    color.set_fg(Some(termcolor::Color::Yellow));
+                }
+                Style::Error => {
+                    color.set_fg(Some(termcolor::Color::Red));
+                    color.set_bold(true);
+                }
+                Style::Hint => {
+                    color.set_dimmed(true);
+                }
+                Style::Default => {}
+            }
+
+            buffer.set_color(&color)?;
+            buffer.write_all(piece.0.as_bytes())?;
+            buffer.reset()?;
+        }
+
+        writer.print(&buffer)
+    }
+
+    #[cfg(not(feature = "color"))]
+    pub(crate) fn print(&self) -> io::Result<()> {
+        // [e]println can't be used here because it panics
+        // if something went wrong. We don't want that.
+        match self.stream {
+            Stream::Stdout => {
+                let stdout = std::io::stdout();
+                let mut stdout = stdout.lock();
+                write!(stdout, "{}", self)
+            }
+            Stream::Stderr => {
+                let stderr = std::io::stderr();
+                let mut stderr = stderr.lock();
+                write!(stderr, "{}", self)
+            }
+        }
+    }
+}
+
+/// Color-unaware printing. Never uses coloring.
+impl Display for Colorizer {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        for piece in &self.pieces {
+            Display::fmt(&piece.0, f)?;
+        }
+
+        Ok(())
+    }
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub enum Style {
+    Good,
+    Warning,
+    Error,
+    Hint,
+    Default,
+}
+
+impl Default for Style {
+    fn default() -> Self {
+        Self::Default
+    }
+}
+
+#[cfg(feature = "color")]
+fn is_a_tty(stream: Stream) -> bool {
+    let stream = match stream {
+        Stream::Stdout => atty::Stream::Stdout,
+        Stream::Stderr => atty::Stream::Stderr,
+    };
+
+    atty::is(stream)
+}
diff --git a/vendor/clap-3.2.20/src/output/help.rs b/vendor/clap-3.2.20/src/output/help.rs
new file mode 100644
index 000000000..eb53bfa54
--- /dev/null
+++ b/vendor/clap-3.2.20/src/output/help.rs
@@ -0,0 +1,1176 @@
+// Std
+use std::borrow::Cow;
+use std::cmp;
+use std::fmt::Write as _;
+use std::io::{self, Write};
+use std::usize;
+
+// Internal
+use crate::builder::{display_arg_val, Arg, Command};
+use crate::output::{fmt::Colorizer, Usage};
+use crate::PossibleValue;
+
+// Third party
+use indexmap::IndexSet;
+use textwrap::core::display_width;
+
+/// `clap` Help Writer.
+///
+/// Wraps a writer stream providing different methods to generate help for `clap` objects.
+pub(crate) struct Help<'help, 'cmd, 'writer> {
+    writer: HelpWriter<'writer>,
+    cmd: &'cmd Command<'help>,
+    usage: &'cmd Usage<'help, 'cmd>,
+    next_line_help: bool,
+    term_w: usize,
+    use_long: bool,
+}
+
+// Public Functions
+impl<'help, 'cmd, 'writer> Help<'help, 'cmd, 'writer> {
+    #[cfg(feature = "unstable-v4")]
+    const DEFAULT_TEMPLATE: &'static str = "\
+        {before-help}{name} {version}\n\
+        {author-with-newline}{about-with-newline}\n\
+        {usage-heading}\n    {usage}\n\
+        \n\
+        {all-args}{after-help}\
+    ";
+    #[cfg(not(feature = "unstable-v4"))]
+    const DEFAULT_TEMPLATE: &'static str = "\
+        {before-help}{bin} {version}\n\
+        {author-with-newline}{about-with-newline}\n\
+        {usage-heading}\n    {usage}\n\
+        \n\
+        {all-args}{after-help}\
+    ";
+
+    #[cfg(feature = "unstable-v4")]
+    const DEFAULT_NO_ARGS_TEMPLATE: &'static str = "\
+        {before-help}{name} {version}\n\
+        {author-with-newline}{about-with-newline}\n\
+        {usage-heading}\n    {usage}{after-help}\
+    ";
+    #[cfg(not(feature = "unstable-v4"))]
+    const DEFAULT_NO_ARGS_TEMPLATE: &'static str = "\
+        {before-help}{bin} {version}\n\
+        {author-with-newline}{about-with-newline}\n\
+        {usage-heading}\n    {usage}{after-help}\
+    ";
+
+    /// Create a new `Help` instance.
+    pub(crate) fn new(
+        writer: HelpWriter<'writer>,
+        cmd: &'cmd Command<'help>,
+        usage: &'cmd Usage<'help, 'cmd>,
+        use_long: bool,
+    ) -> Self {
+        debug!("Help::new cmd={}, use_long={}", cmd.get_name(), use_long);
+        let term_w = match cmd.get_term_width() {
+            Some(0) => usize::MAX,
+            Some(w) => w,
+            None => cmp::min(
+                dimensions().map_or(100, |(w, _)| w),
+                match cmd.get_max_term_width() {
+                    None | Some(0) => usize::MAX,
+                    Some(mw) => mw,
+                },
+            ),
+        };
+        let next_line_help = cmd.is_next_line_help_set();
+
+        Help {
+            writer,
+            cmd,
+            usage,
+            next_line_help,
+            term_w,
+            use_long,
+        }
+    }
+
+    /// Writes the parser help to the wrapped stream.
+    pub(crate) fn write_help(&mut self) -> io::Result<()> {
+        debug!("Help::write_help");
+
+        if let Some(h) = self.cmd.get_override_help() {
+            self.none(h)?;
+        } else if let Some(tmpl) = self.cmd.get_help_template() {
+            self.write_templated_help(tmpl)?;
+        } else {
+            let pos = self
+                .cmd
+                .get_positionals()
+                .any(|arg| should_show_arg(self.use_long, arg));
+            let non_pos = self
+                .cmd
+                .get_non_positionals()
+                .any(|arg| should_show_arg(self.use_long, arg));
+            let subcmds = self.cmd.has_visible_subcommands();
+
+            if non_pos || pos || subcmds {
+                self.write_templated_help(Self::DEFAULT_TEMPLATE)?;
+            } else {
+                self.write_templated_help(Self::DEFAULT_NO_ARGS_TEMPLATE)?;
+            }
+        }
+
+        self.none("\n")?;
+
+        Ok(())
+    }
+}
+
+macro_rules! write_method {
+    ($_self:ident, $msg:ident, $meth:ident) => {
+        match &mut $_self.writer {
+            HelpWriter::Buffer(c) => {
+                c.$meth(($msg).into());
+                Ok(())
+            }
+            HelpWriter::Normal(w) => w.write_all($msg.as_ref()),
+        }
+    };
+}
+
+// Methods to write Arg help.
+impl<'help, 'cmd, 'writer> Help<'help, 'cmd, 'writer> {
+    #[inline(never)]
+    fn good<T: Into<String> + AsRef<[u8]>>(&mut self, msg: T) -> io::Result<()> {
+        write_method!(self, msg, good)
+    }
+
+    #[inline(never)]
+    fn warning<T: Into<String> + AsRef<[u8]>>(&mut self, msg: T) -> io::Result<()> {
+        write_method!(self, msg, warning)
+    }
+
+    #[inline(never)]
+    fn none<T: Into<String> + AsRef<[u8]>>(&mut self, msg: T) -> io::Result<()> {
+        write_method!(self, msg, none)
+    }
+
+    #[inline(never)]
+    fn spaces(&mut self, n: usize) -> io::Result<()> {
+        // A string with 64 consecutive spaces.
+        const SHORT_SPACE: &str =
+            "                                                                ";
+        if let Some(short) = SHORT_SPACE.get(..n) {
+            self.none(short)
+        } else {
+            self.none(" ".repeat(n))
+        }
+    }
+
+    /// Writes help for each argument in the order they were declared to the wrapped stream.
+    fn write_args_unsorted(&mut self, args: &[&Arg<'help>]) -> io::Result<()> {
+        debug!("Help::write_args_unsorted");
+        // The shortest an arg can legally be is 2 (i.e. '-x')
+        let mut longest = 2;
+        let mut arg_v = Vec::with_capacity(10);
+
+        for &arg in args
+            .iter()
+            .filter(|arg| should_show_arg(self.use_long, *arg))
+        {
+            if arg.longest_filter() {
+                longest = longest.max(display_width(&arg.to_string()));
+                debug!(
+                    "Help::write_args_unsorted: arg={:?} longest={}",
+                    arg.get_id(),
+                    longest
+                );
+            }
+            arg_v.push(arg)
+        }
+
+        let next_line_help = self.will_args_wrap(args, longest);
+
+        let argc = arg_v.len();
+        for (i, arg) in arg_v.iter().enumerate() {
+            self.write_arg(arg, i + 1 == argc, next_line_help, longest)?;
+        }
+        Ok(())
+    }
+
+    /// Sorts arguments by length and display order and write their help to the wrapped stream.
+    fn write_args(&mut self, args: &[&Arg<'help>], _category: &str) -> io::Result<()> {
+        debug!("Help::write_args {}", _category);
+        // The shortest an arg can legally be is 2 (i.e. '-x')
+        let mut longest = 2;
+        let mut ord_v = Vec::new();
+
+        // Determine the longest
+        for &arg in args.iter().filter(|arg| {
+            // If it's NextLineHelp we don't care to compute how long it is because it may be
+            // NextLineHelp on purpose simply *because* it's so long and would throw off all other
+            // args alignment
+            should_show_arg(self.use_long, *arg)
+        }) {
+            if arg.longest_filter() {
+                longest = longest.max(display_width(&arg.to_string()));
+                debug!(
+                    "Help::write_args: arg={:?} longest={}",
+                    arg.get_id(),
+                    longest
+                );
+            }
+
+            // Formatting key like this to ensure that:
+            // 1. Argument has long flags are printed just after short flags.
+            // 2. For two args both have short flags like `-c` and `-C`, the
+            //    `-C` arg is printed just after the `-c` arg
+            // 3. For args without short or long flag, print them at last(sorted
+            //    by arg name).
+            // Example order: -a, -b, -B, -s, --select-file, --select-folder, -x
+
+            let key = if let Some(x) = arg.short {
+                let mut s = x.to_ascii_lowercase().to_string();
+                s.push(if x.is_ascii_lowercase() { '0' } else { '1' });
+                s
+            } else if let Some(x) = arg.long {
+                x.to_string()
+            } else {
+                let mut s = '{'.to_string();
+                s.push_str(arg.name);
+                s
+            };
+            ord_v.push((arg.get_display_order(), key, arg));
+        }
+        ord_v.sort_by(|a, b| (a.0, &a.1).cmp(&(b.0, &b.1)));
+
+        let next_line_help = self.will_args_wrap(args, longest);
+
+        for (i, (_, _, arg)) in ord_v.iter().enumerate() {
+            let last_arg = i + 1 == ord_v.len();
+            self.write_arg(arg, last_arg, next_line_help, longest)?;
+        }
+        Ok(())
+    }
+
+    /// Writes help for an argument to the wrapped stream.
+    fn write_arg(
+        &mut self,
+        arg: &Arg<'help>,
+        last_arg: bool,
+        next_line_help: bool,
+        longest: usize,
+    ) -> io::Result<()> {
+        let spec_vals = &self.spec_vals(arg);
+
+        self.short(arg)?;
+        self.long(arg)?;
+        self.val(arg)?;
+        self.align_to_about(arg, next_line_help, longest)?;
+
+        let about = if self.use_long {
+            arg.long_help.or(arg.help).unwrap_or("")
+        } else {
+            arg.help.or(arg.long_help).unwrap_or("")
+        };
+
+        self.help(Some(arg), about, spec_vals, next_line_help, longest)?;
+
+        if !last_arg {
+            self.none("\n")?;
+            if next_line_help {
+                self.none("\n")?;
+            }
+        }
+        Ok(())
+    }
+
+    /// Writes argument's short command to the wrapped stream.
+    fn short(&mut self, arg: &Arg<'help>) -> io::Result<()> {
+        debug!("Help::short");
+
+        self.none(TAB)?;
+
+        if let Some(s) = arg.short {
+            self.good(format!("-{}", s))
+        } else if !arg.is_positional() {
+            self.none(TAB)
+        } else {
+            Ok(())
+        }
+    }
+
+    /// Writes argument's long command to the wrapped stream.
+    fn long(&mut self, arg: &Arg<'help>) -> io::Result<()> {
+        debug!("Help::long");
+        if let Some(long) = arg.long {
+            if arg.short.is_some() {
+                self.none(", ")?;
+            }
+            self.good(format!("--{}", long))?;
+        }
+        Ok(())
+    }
+
+    /// Writes argument's possible values to the wrapped stream.
+    fn val(&mut self, arg: &Arg<'help>) -> io::Result<()> {
+        debug!("Help::val: arg={}", arg.name);
+        let mut need_closing_bracket = false;
+        if arg.is_takes_value_set() && !arg.is_positional() {
+            let is_optional_val = arg.min_vals == Some(0);
+            let sep = if arg.is_require_equals_set() {
+                if is_optional_val {
+                    need_closing_bracket = true;
+                    "[="
+                } else {
+                    "="
+                }
+            } else if is_optional_val {
+                need_closing_bracket = true;
+                " ["
+            } else {
+                " "
+            };
+            self.none(sep)?;
+        }
+
+        if arg.is_takes_value_set() || arg.is_positional() {
+            display_arg_val(
+                arg,
+                |s, good| if good { self.good(s) } else { self.none(s) },
+            )?;
+        }
+
+        if need_closing_bracket {
+            self.none("]")?;
+        }
+        Ok(())
+    }
+
+    /// Write alignment padding between arg's switches/values and its about message.
+    fn align_to_about(
+        &mut self,
+        arg: &Arg<'help>,
+        next_line_help: bool,
+        longest: usize,
+    ) -> io::Result<()> {
+        debug!(
+            "Help::align_to_about: arg={}, next_line_help={}, longest={}",
+            arg.name, next_line_help, longest
+        );
+        if self.use_long || next_line_help {
+            // long help prints messages on the next line so it doesn't need to align text
+            debug!("Help::align_to_about: printing long help so skip alignment");
+        } else if !arg.is_positional() {
+            let self_len = display_width(&arg.to_string());
+            // Since we're writing spaces from the tab point we first need to know if we
+            // had a long and short, or just short
+            let padding = if arg.long.is_some() {
+                // Only account 4 after the val
+                4
+            } else {
+                // Only account for ', --' + 4 after the val
+                8
+            };
+            let spcs = longest + padding - self_len;
+            debug!(
+                "Help::align_to_about: positional=false arg_len={}, spaces={}",
+                self_len, spcs
+            );
+
+            self.spaces(spcs)?;
+        } else {
+            let self_len = display_width(&arg.to_string());
+            let padding = 4;
+            let spcs = longest + padding - self_len;
+            debug!(
+                "Help::align_to_about: positional=true arg_len={}, spaces={}",
+                self_len, spcs
+            );
+
+            self.spaces(spcs)?;
+        }
+        Ok(())
+    }
+
+    fn write_before_help(&mut self) -> io::Result<()> {
+        debug!("Help::write_before_help");
+        let before_help = if self.use_long {
+            self.cmd
+                .get_before_long_help()
+                .or_else(|| self.cmd.get_before_help())
+        } else {
+            self.cmd.get_before_help()
+        };
+        if let Some(output) = before_help {
+            self.none(text_wrapper(&output.replace("{n}", "\n"), self.term_w))?;
+            self.none("\n\n")?;
+        }
+        Ok(())
+    }
+
+    fn write_after_help(&mut self) -> io::Result<()> {
+        debug!("Help::write_after_help");
+        let after_help = if self.use_long {
+            self.cmd
+                .get_after_long_help()
+                .or_else(|| self.cmd.get_after_help())
+        } else {
+            self.cmd.get_after_help()
+        };
+        if let Some(output) = after_help {
+            self.none("\n\n")?;
+            self.none(text_wrapper(&output.replace("{n}", "\n"), self.term_w))?;
+        }
+        Ok(())
+    }
+
+    /// Writes argument's help to the wrapped stream.
+    fn help(
+        &mut self,
+        arg: Option<&Arg<'help>>,
+        about: &str,
+        spec_vals: &str,
+        next_line_help: bool,
+        longest: usize,
+    ) -> io::Result<()> {
+        debug!("Help::help");
+        let mut help = String::from(about) + spec_vals;
+        debug!("Help::help: Next Line...{:?}", next_line_help);
+
+        let spaces = if next_line_help {
+            12 // "tab" * 3
+        } else {
+            longest + 12
+        };
+
+        let too_long = spaces + display_width(&help) >= self.term_w;
+
+        // Is help on next line, if so then indent
+        if next_line_help {
+            self.none(format!("\n{}{}{}", TAB, TAB, TAB))?;
+        }
+
+        debug!("Help::help: Too long...");
+        if too_long && spaces <= self.term_w || help.contains("{n}") {
+            debug!("Yes");
+            debug!("Help::help: help...{}", help);
+            debug!("Help::help: help width...{}", display_width(&help));
+            // Determine how many newlines we need to insert
+            let avail_chars = self.term_w - spaces;
+            debug!("Help::help: Usable space...{}", avail_chars);
+            help = text_wrapper(&help.replace("{n}", "\n"), avail_chars);
+        } else {
+            debug!("No");
+        }
+        if let Some(part) = help.lines().next() {
+            self.none(part)?;
+        }
+
+        // indent of help
+        let spaces = if next_line_help {
+            TAB_WIDTH * 3
+        } else if let Some(true) = arg.map(|a| a.is_positional()) {
+            longest + TAB_WIDTH * 2
+        } else {
+            longest + TAB_WIDTH * 3
+        };
+
+        for part in help.lines().skip(1) {
+            self.none("\n")?;
+            self.spaces(spaces)?;
+            self.none(part)?;
+        }
+
+        #[cfg(feature = "unstable-v4")]
+        if let Some(arg) = arg {
+            const DASH_SPACE: usize = "- ".len();
+            const COLON_SPACE: usize = ": ".len();
+            let possible_vals = arg.get_possible_values2();
+            if self.use_long
+                && !arg.is_hide_possible_values_set()
+                && possible_vals.iter().any(PossibleValue::should_show_help)
+            {
+                debug!("Help::help: Found possible vals...{:?}", possible_vals);
+                if !help.is_empty() {
+                    self.none("\n\n")?;
+                    self.spaces(spaces)?;
+                }
+                self.none("Possible values:")?;
+                let longest = possible_vals
+                    .iter()
+                    .filter_map(|f| f.get_visible_quoted_name().map(|name| display_width(&name)))
+                    .max()
+                    .expect("Only called with possible value");
+                let help_longest = possible_vals
+                    .iter()
+                    .filter_map(|f| f.get_visible_help().map(display_width))
+                    .max()
+                    .expect("Only called with possible value with help");
+                // should new line
+                let taken = longest + spaces + DASH_SPACE;
+
+                let possible_value_new_line =
+                    self.term_w >= taken && self.term_w < taken + COLON_SPACE + help_longest;
+
+                let spaces = spaces + TAB_WIDTH - DASH_SPACE;
+                let spaces_help = if possible_value_new_line {
+                    spaces + DASH_SPACE
+                } else {
+                    spaces + longest + DASH_SPACE + COLON_SPACE
+                };
+
+                for pv in possible_vals.iter().filter(|pv| !pv.is_hide_set()) {
+                    self.none("\n")?;
+                    self.spaces(spaces)?;
+                    self.none("- ")?;
+                    self.good(pv.get_name())?;
+                    if let Some(help) = pv.get_help() {
+                        debug!("Help::help: Possible Value help");
+
+                        if possible_value_new_line {
+                            self.none(":\n")?;
+                            self.spaces(spaces_help)?;
+                        } else {
+                            self.none(": ")?;
+                            // To align help messages
+                            self.spaces(longest - display_width(pv.get_name()))?;
+                        }
+
+                        let avail_chars = if self.term_w > spaces_help {
+                            self.term_w - spaces_help
+                        } else {
+                            usize::MAX
+                        };
+
+                        let help = text_wrapper(help, avail_chars);
+                        let mut help = help.lines();
+
+                        self.none(help.next().unwrap_or_default())?;
+                        for part in help {
+                            self.none("\n")?;
+                            self.spaces(spaces_help)?;
+                            self.none(part)?;
+                        }
+                    }
+                }
+            }
+        }
+        Ok(())
+    }
+
+    /// Will use next line help on writing args.
+    fn will_args_wrap(&self, args: &[&Arg<'help>], longest: usize) -> bool {
+        args.iter()
+            .filter(|arg| should_show_arg(self.use_long, *arg))
+            .any(|arg| {
+                let spec_vals = &self.spec_vals(arg);
+                self.arg_next_line_help(arg, spec_vals, longest)
+            })
+    }
+
+    fn arg_next_line_help(&self, arg: &Arg<'help>, spec_vals: &str, longest: usize) -> bool {
+        if self.next_line_help || arg.is_next_line_help_set() || self.use_long {
+            // setting_next_line
+            true
+        } else {
+            // force_next_line
+            let h = arg.help.unwrap_or("");
+            let h_w = display_width(h) + display_width(spec_vals);
+            let taken = longest + 12;
+            self.term_w >= taken
+                && (taken as f32 / self.term_w as f32) > 0.40
+                && h_w > (self.term_w - taken)
+        }
+    }
+
+    fn spec_vals(&self, a: &Arg) -> String {
+        debug!("Help::spec_vals: a={}", a);
+        let mut spec_vals = vec![];
+        #[cfg(feature = "env")]
+        if let Some(ref env) = a.env {
+            if !a.is_hide_env_set() {
+                debug!(
+                    "Help::spec_vals: Found environment variable...[{:?}:{:?}]",
+                    env.0, env.1
+                );
+                let env_val = if !a.is_hide_env_values_set() {
+                    format!(
+                        "={}",
+                        env.1
+                            .as_ref()
+                            .map_or(Cow::Borrowed(""), |val| val.to_string_lossy())
+                    )
+                } else {
+                    String::new()
+                };
+                let env_info = format!("[env: {}{}]", env.0.to_string_lossy(), env_val);
+                spec_vals.push(env_info);
+            }
+        }
+        if a.is_takes_value_set() && !a.is_hide_default_value_set() && !a.default_vals.is_empty() {
+            debug!(
+                "Help::spec_vals: Found default value...[{:?}]",
+                a.default_vals
+            );
+
+            let pvs = a
+                .default_vals
+                .iter()
+                .map(|&pvs| pvs.to_string_lossy())
+                .map(|pvs| {
+                    if pvs.contains(char::is_whitespace) {
+                        Cow::from(format!("{:?}", pvs))
+                    } else {
+                        pvs
+                    }
+                })
+                .collect::<Vec<_>>()
+                .join(" ");
+
+            spec_vals.push(format!("[default: {}]", pvs));
+        }
+        if !a.aliases.is_empty() {
+            debug!("Help::spec_vals: Found aliases...{:?}", a.aliases);
+
+            let als = a
+                .aliases
+                .iter()
+                .filter(|&als| als.1) // visible
+                .map(|&als| als.0) // name
+                .collect::<Vec<_>>()
+                .join(", ");
+
+            if !als.is_empty() {
+                spec_vals.push(format!("[aliases: {}]", als));
+            }
+        }
+
+        if !a.short_aliases.is_empty() {
+            debug!(
+                "Help::spec_vals: Found short aliases...{:?}",
+                a.short_aliases
+            );
+
+            let als = a
+                .short_aliases
+                .iter()
+                .filter(|&als| als.1) // visible
+                .map(|&als| als.0.to_string()) // name
+                .collect::<Vec<_>>()
+                .join(", ");
+
+            if !als.is_empty() {
+                spec_vals.push(format!("[short aliases: {}]", als));
+            }
+        }
+
+        let possible_vals = a.get_possible_values2();
+        if !(a.is_hide_possible_values_set()
+            || possible_vals.is_empty()
+            || cfg!(feature = "unstable-v4")
+                && self.use_long
+                && possible_vals.iter().any(PossibleValue::should_show_help))
+        {
+            debug!("Help::spec_vals: Found possible vals...{:?}", possible_vals);
+
+            let pvs = possible_vals
+                .iter()
+                .filter_map(PossibleValue::get_visible_quoted_name)
+                .collect::<Vec<_>>()
+                .join(", ");
+
+            spec_vals.push(format!("[possible values: {}]", pvs));
+        }
+        let connector = if self.use_long { "\n" } else { " " };
+        let prefix = if !spec_vals.is_empty() && !a.get_help().unwrap_or("").is_empty() {
+            if self.use_long {
+                "\n\n"
+            } else {
+                " "
+            }
+        } else {
+            ""
+        };
+        prefix.to_string() + &spec_vals.join(connector)
+    }
+
+    fn write_about(&mut self, before_new_line: bool, after_new_line: bool) -> io::Result<()> {
+        let about = if self.use_long {
+            self.cmd.get_long_about().or_else(|| self.cmd.get_about())
+        } else {
+            self.cmd.get_about()
+        };
+        if let Some(output) = about {
+            if before_new_line {
+                self.none("\n")?;
+            }
+            self.none(text_wrapper(output, self.term_w))?;
+            if after_new_line {
+                self.none("\n")?;
+            }
+        }
+        Ok(())
+    }
+
+    fn write_author(&mut self, before_new_line: bool, after_new_line: bool) -> io::Result<()> {
+        if let Some(author) = self.cmd.get_author() {
+            if before_new_line {
+                self.none("\n")?;
+            }
+            self.none(text_wrapper(author, self.term_w))?;
+            if after_new_line {
+                self.none("\n")?;
+            }
+        }
+        Ok(())
+    }
+
+    fn write_version(&mut self) -> io::Result<()> {
+        let version = self
+            .cmd
+            .get_version()
+            .or_else(|| self.cmd.get_long_version());
+        if let Some(output) = version {
+            self.none(text_wrapper(output, self.term_w))?;
+        }
+        Ok(())
+    }
+}
+
+/// Methods to write a single subcommand
+impl<'help, 'cmd, 'writer> Help<'help, 'cmd, 'writer> {
+    fn write_subcommand(
+        &mut self,
+        sc_str: &str,
+        cmd: &Command<'help>,
+        next_line_help: bool,
+        longest: usize,
+    ) -> io::Result<()> {
+        debug!("Help::write_subcommand");
+
+        let spec_vals = &self.sc_spec_vals(cmd);
+
+        let about = cmd
+            .get_about()
+            .or_else(|| cmd.get_long_about())
+            .unwrap_or("");
+
+        self.subcmd(sc_str, next_line_help, longest)?;
+        self.help(None, about, spec_vals, next_line_help, longest)
+    }
+
+    fn sc_spec_vals(&self, a: &Command) -> String {
+        debug!("Help::sc_spec_vals: a={}", a.get_name());
+        let mut spec_vals = vec![];
+        if 0 < a.get_all_aliases().count() || 0 < a.get_all_short_flag_aliases().count() {
+            debug!(
+                "Help::spec_vals: Found aliases...{:?}",
+                a.get_all_aliases().collect::<Vec<_>>()
+            );
+            debug!(
+                "Help::spec_vals: Found short flag aliases...{:?}",
+                a.get_all_short_flag_aliases().collect::<Vec<_>>()
+            );
+
+            let mut short_als = a
+                .get_visible_short_flag_aliases()
+                .map(|a| format!("-{}", a))
+                .collect::<Vec<_>>();
+
+            let als = a.get_visible_aliases().map(|s| s.to_string());
+
+            short_als.extend(als);
+
+            let all_als = short_als.join(", ");
+
+            if !all_als.is_empty() {
+                spec_vals.push(format!(" [aliases: {}]", all_als));
+            }
+        }
+        spec_vals.join(" ")
+    }
+
+    fn subcommand_next_line_help(
+        &self,
+        cmd: &Command<'help>,
+        spec_vals: &str,
+        longest: usize,
+    ) -> bool {
+        if self.next_line_help | self.use_long {
+            // setting_next_line
+            true
+        } else {
+            // force_next_line
+            let h = cmd.get_about().unwrap_or("");
+            let h_w = display_width(h) + display_width(spec_vals);
+            let taken = longest + 12;
+            self.term_w >= taken
+                && (taken as f32 / self.term_w as f32) > 0.40
+                && h_w > (self.term_w - taken)
+        }
+    }
+
+    /// Writes subcommand to the wrapped stream.
+    fn subcmd(&mut self, sc_str: &str, next_line_help: bool, longest: usize) -> io::Result<()> {
+        self.none(TAB)?;
+        self.good(sc_str)?;
+        if !next_line_help {
+            let width = display_width(sc_str);
+            self.spaces(width.max(longest + 4) - width)?;
+        }
+        Ok(())
+    }
+}
+
+// Methods to write Parser help.
+impl<'help, 'cmd, 'writer> Help<'help, 'cmd, 'writer> {
+    /// Writes help for all arguments (options, flags, args, subcommands)
+    /// including titles of a Parser Object to the wrapped stream.
+    pub(crate) fn write_all_args(&mut self) -> io::Result<()> {
+        debug!("Help::write_all_args");
+        let pos = self
+            .cmd
+            .get_positionals_with_no_heading()
+            .filter(|arg| should_show_arg(self.use_long, arg))
+            .collect::<Vec<_>>();
+        let non_pos = self
+            .cmd
+            .get_non_positionals_with_no_heading()
+            .filter(|arg| should_show_arg(self.use_long, arg))
+            .collect::<Vec<_>>();
+        let subcmds = self.cmd.has_visible_subcommands();
+
+        let custom_headings = self
+            .cmd
+            .get_arguments()
+            .filter_map(|arg| arg.get_help_heading())
+            .collect::<IndexSet<_>>();
+
+        let mut first = if !pos.is_empty() {
+            // Write positional args if any
+            self.warning("ARGS:\n")?;
+            self.write_args_unsorted(&pos)?;
+            false
+        } else {
+            true
+        };
+
+        if !non_pos.is_empty() {
+            if !first {
+                self.none("\n\n")?;
+            }
+            self.warning("OPTIONS:\n")?;
+            self.write_args(&non_pos, "OPTIONS")?;
+            first = false;
+        }
+        if !custom_headings.is_empty() {
+            for heading in custom_headings {
+                let args = self
+                    .cmd
+                    .get_arguments()
+                    .filter(|a| {
+                        if let Some(help_heading) = a.get_help_heading() {
+                            return help_heading == heading;
+                        }
+                        false
+                    })
+                    .filter(|arg| should_show_arg(self.use_long, arg))
+                    .collect::<Vec<_>>();
+
+                if !args.is_empty() {
+                    if !first {
+                        self.none("\n\n")?;
+                    }
+                    self.warning(format!("{}:\n", heading))?;
+                    self.write_args(&args, heading)?;
+                    first = false
+                }
+            }
+        }
+
+        if subcmds {
+            if !first {
+                self.none("\n\n")?;
+            }
+
+            self.warning(
+                self.cmd
+                    .get_subcommand_help_heading()
+                    .unwrap_or("SUBCOMMANDS"),
+            )?;
+            self.warning(":\n")?;
+
+            self.write_subcommands(self.cmd)?;
+        }
+
+        Ok(())
+    }
+
+    /// Will use next line help on writing subcommands.
+    fn will_subcommands_wrap<'a>(
+        &self,
+        subcommands: impl IntoIterator<Item = &'a Command<'help>>,
+        longest: usize,
+    ) -> bool
+    where
+        'help: 'a,
+    {
+        subcommands
+            .into_iter()
+            .filter(|&subcommand| should_show_subcommand(subcommand))
+            .any(|subcommand| {
+                let spec_vals = &self.sc_spec_vals(subcommand);
+                self.subcommand_next_line_help(subcommand, spec_vals, longest)
+            })
+    }
+
+    /// Writes help for subcommands of a Parser Object to the wrapped stream.
+    fn write_subcommands(&mut self, cmd: &Command<'help>) -> io::Result<()> {
+        debug!("Help::write_subcommands");
+        // The shortest an arg can legally be is 2 (i.e. '-x')
+        let mut longest = 2;
+        let mut ord_v = Vec::new();
+        for subcommand in cmd
+            .get_subcommands()
+            .filter(|subcommand| should_show_subcommand(subcommand))
+        {
+            let mut sc_str = String::new();
+            sc_str.push_str(subcommand.get_name());
+            if let Some(short) = subcommand.get_short_flag() {
+                write!(sc_str, " -{}", short).unwrap();
+            }
+            if let Some(long) = subcommand.get_long_flag() {
+                write!(sc_str, " --{}", long).unwrap();
+            }
+            longest = longest.max(display_width(&sc_str));
+            ord_v.push((subcommand.get_display_order(), sc_str, subcommand));
+        }
+        ord_v.sort_by(|a, b| (a.0, &a.1).cmp(&(b.0, &b.1)));
+
+        debug!("Help::write_subcommands longest = {}", longest);
+
+        let next_line_help = self.will_subcommands_wrap(cmd.get_subcommands(), longest);
+
+        let mut first = true;
+        for (_, sc_str, sc) in &ord_v {
+            if first {
+                first = false;
+            } else {
+                self.none("\n")?;
+            }
+            self.write_subcommand(sc_str, sc, next_line_help, longest)?;
+        }
+        Ok(())
+    }
+
+    /// Writes binary name of a Parser Object to the wrapped stream.
+    fn write_display_name(&mut self) -> io::Result<()> {
+        debug!("Help::write_display_name");
+
+        let display_name = text_wrapper(
+            &self
+                .cmd
+                .get_display_name()
+                .unwrap_or_else(|| self.cmd.get_name())
+                .replace("{n}", "\n"),
+            self.term_w,
+        );
+        self.good(&display_name)?;
+        Ok(())
+    }
+
+    /// Writes binary name of a Parser Object to the wrapped stream.
+    fn write_bin_name(&mut self) -> io::Result<()> {
+        debug!("Help::write_bin_name");
+
+        let bin_name = if let Some(bn) = self.cmd.get_bin_name() {
+            if bn.contains(' ') {
+                // In case we're dealing with subcommands i.e. git mv is translated to git-mv
+                bn.replace(' ', "-")
+            } else {
+                text_wrapper(&self.cmd.get_name().replace("{n}", "\n"), self.term_w)
+            }
+        } else {
+            text_wrapper(&self.cmd.get_name().replace("{n}", "\n"), self.term_w)
+        };
+        self.good(&bin_name)?;
+        Ok(())
+    }
+}
+
+// Methods to write Parser help using templates.
+impl<'help, 'cmd, 'writer> Help<'help, 'cmd, 'writer> {
+    /// Write help to stream for the parser in the format defined by the template.
+    ///
+    /// For details about the template language see [`Command::help_template`].
+    ///
+    /// [`Command::help_template`]: Command::help_template()
+    fn write_templated_help(&mut self, template: &str) -> io::Result<()> {
+        debug!("Help::write_templated_help");
+
+        // The strategy is to copy the template from the reader to wrapped stream
+        // until a tag is found. Depending on its value, the appropriate content is copied
+        // to the wrapped stream.
+        // The copy from template is then resumed, repeating this sequence until reading
+        // the complete template.
+
+        macro_rules! tags {
+            (
+                match $part:ident {
+                    $( $tag:expr => $action:stmt )*
+                }
+            ) => {
+                match $part {
+                    $(
+                        part if part.starts_with(concat!($tag, "}")) => {
+                            $action
+                            let rest = &part[$tag.len()+1..];
+                            self.none(rest)?;
+                        }
+                    )*
+
+                    // Unknown tag, write it back.
+                    part => {
+                        self.none("{")?;
+                        self.none(part)?;
+                    }
+                }
+            };
+        }
+
+        let mut parts = template.split('{');
+        if let Some(first) = parts.next() {
+            self.none(first)?;
+        }
+
+        for part in parts {
+            tags! {
+                match part {
+                    "name" => {
+                        self.write_display_name()?;
+                    }
+                    "bin" => {
+                        self.write_bin_name()?;
+                    }
+                    "version" => {
+                        self.write_version()?;
+                    }
+                    "author" => {
+                        self.write_author(false, false)?;
+                    }
+                    "author-with-newline" => {
+                        self.write_author(false, true)?;
+                    }
+                    "author-section" => {
+                        self.write_author(true, true)?;
+                    }
+                    "about" => {
+                        self.write_about(false, false)?;
+                    }
+                    "about-with-newline" => {
+                        self.write_about(false, true)?;
+                    }
+                    "about-section" => {
+                        self.write_about(true, true)?;
+                    }
+                    "usage-heading" => {
+                        self.warning("USAGE:")?;
+                    }
+                    "usage" => {
+                        self.none(self.usage.create_usage_no_title(&[]))?;
+                    }
+                    "all-args" => {
+                        self.write_all_args()?;
+                    }
+                    "options" => {
+                        // Include even those with a heading as we don't have a good way of
+                        // handling help_heading in the template.
+                        self.write_args(&self.cmd.get_non_positionals().collect::<Vec<_>>(), "options")?;
+                    }
+                    "positionals" => {
+                        self.write_args(&self.cmd.get_positionals().collect::<Vec<_>>(), "positionals")?;
+                    }
+                    "subcommands" => {
+                        self.write_subcommands(self.cmd)?;
+                    }
+                    "after-help" => {
+                        self.write_after_help()?;
+                    }
+                    "before-help" => {
+                        self.write_before_help()?;
+                    }
+                }
+            }
+        }
+
+        Ok(())
+    }
+}
+
+pub(crate) fn dimensions() -> Option<(usize, usize)> {
+    #[cfg(not(feature = "wrap_help"))]
+    return None;
+
+    #[cfg(feature = "wrap_help")]
+    terminal_size::terminal_size().map(|(w, h)| (w.0.into(), h.0.into()))
+}
+
+const TAB: &str = "    ";
+const TAB_WIDTH: usize = 4;
+
+pub(crate) enum HelpWriter<'writer> {
+    Normal(&'writer mut dyn Write),
+    Buffer(&'writer mut Colorizer),
+}
+
+fn should_show_arg(use_long: bool, arg: &Arg) -> bool {
+    debug!("should_show_arg: use_long={:?}, arg={}", use_long, arg.name);
+    if arg.is_hide_set() {
+        return false;
+    }
+    (!arg.is_hide_long_help_set() && use_long)
+        || (!arg.is_hide_short_help_set() && !use_long)
+        || arg.is_next_line_help_set()
+}
+
+fn should_show_subcommand(subcommand: &Command) -> bool {
+    !subcommand.is_hide_set()
+}
+
+fn text_wrapper(help: &str, width: usize) -> String {
+    let wrapper = textwrap::Options::new(width)
+        .break_words(false)
+        .word_splitter(textwrap::WordSplitter::NoHyphenation);
+    help.lines()
+        .map(|line| textwrap::fill(line, &wrapper))
+        .collect::<Vec<String>>()
+        .join("\n")
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn wrap_help_last_word() {
+        let help = String::from("foo bar baz");
+        assert_eq!(text_wrapper(&help, 5), "foo\nbar\nbaz");
+    }
+
+    #[test]
+    fn display_width_handles_non_ascii() {
+        // Popular Danish tongue-twister, the name of a fruit dessert.
+        let text = "rødgrød med fløde";
+        assert_eq!(display_width(text), 17);
+        // Note that the string width is smaller than the string
+        // length. This is due to the precomposed non-ASCII letters:
+        assert_eq!(text.len(), 20);
+    }
+
+    #[test]
+    fn display_width_handles_emojis() {
+        let text = "😂";
+        // There is a single `char`...
+        assert_eq!(text.chars().count(), 1);
+        // but it is double-width:
+        assert_eq!(display_width(text), 2);
+        // This is much less than the byte length:
+        assert_eq!(text.len(), 4);
+    }
+}
diff --git a/vendor/clap-3.2.20/src/output/mod.rs b/vendor/clap-3.2.20/src/output/mod.rs
new file mode 100644
index 000000000..e32aac26a
--- /dev/null
+++ b/vendor/clap-3.2.20/src/output/mod.rs
@@ -0,0 +1,7 @@
+mod help;
+mod usage;
+
+pub(crate) mod fmt;
+
+pub(crate) use self::help::{Help, HelpWriter};
+pub(crate) use self::usage::Usage;
diff --git a/vendor/clap-3.2.20/src/output/usage.rs b/vendor/clap-3.2.20/src/output/usage.rs
new file mode 100644
index 000000000..6f7a2cad4
--- /dev/null
+++ b/vendor/clap-3.2.20/src/output/usage.rs
@@ -0,0 +1,449 @@
+use indexmap::IndexSet;
+
+// Internal
+use crate::builder::AppSettings as AS;
+use crate::builder::{Arg, ArgPredicate, Command};
+use crate::parser::ArgMatcher;
+use crate::util::ChildGraph;
+use crate::util::Id;
+use crate::INTERNAL_ERROR_MSG;
+
+pub(crate) struct Usage<'help, 'cmd> {
+    cmd: &'cmd Command<'help>,
+    required: Option<&'cmd ChildGraph<Id>>,
+}
+
+impl<'help, 'cmd> Usage<'help, 'cmd> {
+    pub(crate) fn new(cmd: &'cmd Command<'help>) -> Self {
+        Usage {
+            cmd,
+            required: None,
+        }
+    }
+
+    pub(crate) fn required(mut self, required: &'cmd ChildGraph<Id>) -> Self {
+        self.required = Some(required);
+        self
+    }
+
+    // Creates a usage string for display. This happens just after all arguments were parsed, but before
+    // any subcommands have been parsed (so as to give subcommands their own usage recursively)
+    pub(crate) fn create_usage_with_title(&self, used: &[Id]) -> String {
+        debug!("Usage::create_usage_with_title");
+        let mut usage = String::with_capacity(75);
+        usage.push_str("USAGE:\n    ");
+        usage.push_str(&*self.create_usage_no_title(used));
+        usage
+    }
+
+    // Creates a usage string (*without title*) if one was not provided by the user manually.
+    pub(crate) fn create_usage_no_title(&self, used: &[Id]) -> String {
+        debug!("Usage::create_usage_no_title");
+        if let Some(u) = self.cmd.get_override_usage() {
+            String::from(&*u)
+        } else if used.is_empty() {
+            self.create_help_usage(true)
+        } else {
+            self.create_smart_usage(used)
+        }
+    }
+
+    // Creates a usage string for display in help messages (i.e. not for errors)
+    fn create_help_usage(&self, incl_reqs: bool) -> String {
+        debug!("Usage::create_help_usage; incl_reqs={:?}", incl_reqs);
+        let mut usage = String::with_capacity(75);
+        let name = self
+            .cmd
+            .get_usage_name()
+            .or_else(|| self.cmd.get_bin_name())
+            .unwrap_or_else(|| self.cmd.get_name());
+        usage.push_str(name);
+        let req_string = if incl_reqs {
+            self.get_required_usage_from(&[], None, false)
+                .iter()
+                .fold(String::new(), |a, s| a + " " + s)
+        } else {
+            String::new()
+        };
+
+        if self.needs_options_tag() {
+            usage.push_str(" [OPTIONS]");
+        }
+
+        let allow_missing_positional = self.cmd.is_allow_missing_positional_set();
+        if !allow_missing_positional {
+            usage.push_str(&req_string);
+        }
+
+        let has_last = self.cmd.get_positionals().any(|p| p.is_last_set());
+        // places a '--' in the usage string if there are args and options
+        // supporting multiple values
+        if self
+            .cmd
+            .get_non_positionals()
+            .any(|o| o.is_multiple_values_set())
+            && self.cmd.get_positionals().any(|p| !p.is_required_set())
+            && !(self.cmd.has_visible_subcommands() || self.cmd.is_allow_external_subcommands_set())
+            && !has_last
+        {
+            usage.push_str(" [--]");
+        }
+        let not_req_or_hidden =
+            |p: &Arg| (!p.is_required_set() || p.is_last_set()) && !p.is_hide_set();
+        if self.cmd.get_positionals().any(not_req_or_hidden) {
+            if let Some(args_tag) = self.get_args_tag(incl_reqs) {
+                usage.push_str(&*args_tag);
+            } else {
+                usage.push_str(" [ARGS]");
+            }
+            if has_last && incl_reqs {
+                let pos = self
+                    .cmd
+                    .get_positionals()
+                    .find(|p| p.is_last_set())
+                    .expect(INTERNAL_ERROR_MSG);
+                debug!("Usage::create_help_usage: '{}' has .last(true)", pos.name);
+                let req = pos.is_required_set();
+                if req && self.cmd.get_positionals().any(|p| !p.is_required_set()) {
+                    usage.push_str(" -- <");
+                } else if req {
+                    usage.push_str(" [--] <");
+                } else {
+                    usage.push_str(" [-- <");
+                }
+                usage.push_str(&*pos.name_no_brackets());
+                usage.push('>');
+                usage.push_str(pos.multiple_str());
+                if !req {
+                    usage.push(']');
+                }
+            }
+        }
+
+        if allow_missing_positional {
+            usage.push_str(&req_string);
+        }
+
+        // incl_reqs is only false when this function is called recursively
+        if self.cmd.has_visible_subcommands() && incl_reqs
+            || self.cmd.is_allow_external_subcommands_set()
+        {
+            let placeholder = self.cmd.get_subcommand_value_name().unwrap_or("SUBCOMMAND");
+            #[allow(deprecated)]
+            if self.cmd.is_subcommand_negates_reqs_set()
+                || self.cmd.is_args_conflicts_with_subcommands_set()
+            {
+                usage.push_str("\n    ");
+                if !self.cmd.is_args_conflicts_with_subcommands_set() {
+                    usage.push_str(&*self.create_help_usage(false));
+                } else {
+                    usage.push_str(&*name);
+                }
+                usage.push_str(" <");
+                usage.push_str(placeholder);
+                usage.push('>');
+            } else if self.cmd.is_subcommand_required_set()
+                || self.cmd.is_set(AS::SubcommandRequiredElseHelp)
+            {
+                usage.push_str(" <");
+                usage.push_str(placeholder);
+                usage.push('>');
+            } else {
+                usage.push_str(" [");
+                usage.push_str(placeholder);
+                usage.push(']');
+            }
+        }
+        let usage = usage.trim().to_owned();
+        debug!("Usage::create_help_usage: usage={}", usage);
+        usage
+    }
+
+    // Creates a context aware usage string, or "smart usage" from currently used
+    // args, and requirements
+    fn create_smart_usage(&self, used: &[Id]) -> String {
+        debug!("Usage::create_smart_usage");
+        let mut usage = String::with_capacity(75);
+
+        let r_string = self
+            .get_required_usage_from(used, None, true)
+            .iter()
+            .fold(String::new(), |acc, s| acc + " " + s);
+
+        usage.push_str(
+            self.cmd
+                .get_usage_name()
+                .or_else(|| self.cmd.get_bin_name())
+                .unwrap_or_else(|| self.cmd.get_name()),
+        );
+        usage.push_str(&*r_string);
+        if self.cmd.is_subcommand_required_set() {
+            usage.push_str(" <");
+            usage.push_str(self.cmd.get_subcommand_value_name().unwrap_or("SUBCOMMAND"));
+            usage.push('>');
+        }
+        usage.shrink_to_fit();
+        usage
+    }
+
+    // Gets the `[ARGS]` tag for the usage string
+    fn get_args_tag(&self, incl_reqs: bool) -> Option<String> {
+        debug!("Usage::get_args_tag; incl_reqs = {:?}", incl_reqs);
+        let mut count = 0;
+        for pos in self
+            .cmd
+            .get_positionals()
+            .filter(|pos| !pos.is_required_set())
+            .filter(|pos| !pos.is_hide_set())
+            .filter(|pos| !pos.is_last_set())
+        {
+            debug!("Usage::get_args_tag:iter:{}", pos.name);
+            let required = self.cmd.groups_for_arg(&pos.id).any(|grp_s| {
+                debug!("Usage::get_args_tag:iter:{:?}:iter:{:?}", pos.name, grp_s);
+                // if it's part of a required group we don't want to count it
+                self.cmd.get_groups().any(|g| g.required && (g.id == grp_s))
+            });
+            if !required {
+                count += 1;
+                debug!(
+                    "Usage::get_args_tag:iter: {} Args not required or hidden",
+                    count
+                );
+            }
+        }
+
+        if !self.cmd.is_dont_collapse_args_in_usage_set() && count > 1 {
+            debug!("Usage::get_args_tag:iter: More than one, returning [ARGS]");
+
+            // [ARGS]
+            None
+        } else if count == 1 && incl_reqs {
+            let pos = self
+                .cmd
+                .get_positionals()
+                .find(|pos| {
+                    !pos.is_required_set()
+                        && !pos.is_hide_set()
+                        && !pos.is_last_set()
+                        && !self.cmd.groups_for_arg(&pos.id).any(|grp_s| {
+                            debug!("Usage::get_args_tag:iter:{:?}:iter:{:?}", pos.name, grp_s);
+                            // if it's part of a required group we don't want to count it
+                            self.cmd.get_groups().any(|g| g.required && (g.id == grp_s))
+                        })
+                })
+                .expect(INTERNAL_ERROR_MSG);
+
+            debug!(
+                "Usage::get_args_tag:iter: Exactly one, returning '{}'",
+                pos.name
+            );
+
+            Some(format!(
+                " [{}]{}",
+                pos.name_no_brackets(),
+                pos.multiple_str()
+            ))
+        } else if self.cmd.is_dont_collapse_args_in_usage_set()
+            && self.cmd.has_positionals()
+            && incl_reqs
+        {
+            debug!("Usage::get_args_tag:iter: Don't collapse returning all");
+            Some(
+                self.cmd
+                    .get_positionals()
+                    .filter(|pos| !pos.is_required_set())
+                    .filter(|pos| !pos.is_hide_set())
+                    .filter(|pos| !pos.is_last_set())
+                    .map(|pos| format!(" [{}]{}", pos.name_no_brackets(), pos.multiple_str()))
+                    .collect::<Vec<_>>()
+                    .join(""),
+            )
+        } else if !incl_reqs {
+            debug!("Usage::get_args_tag:iter: incl_reqs=false, building secondary usage string");
+            let highest_req_pos = self
+                .cmd
+                .get_positionals()
+                .filter_map(|pos| {
+                    if pos.is_required_set() && !pos.is_last_set() {
+                        Some(pos.index)
+                    } else {
+                        None
+                    }
+                })
+                .max()
+                .unwrap_or_else(|| Some(self.cmd.get_positionals().count()));
+            Some(
+                self.cmd
+                    .get_positionals()
+                    .filter(|pos| pos.index <= highest_req_pos)
+                    .filter(|pos| !pos.is_required_set())
+                    .filter(|pos| !pos.is_hide_set())
+                    .filter(|pos| !pos.is_last_set())
+                    .map(|pos| format!(" [{}]{}", pos.name_no_brackets(), pos.multiple_str()))
+                    .collect::<Vec<_>>()
+                    .join(""),
+            )
+        } else {
+            Some("".into())
+        }
+    }
+
+    // Determines if we need the `[OPTIONS]` tag in the usage string
+    fn needs_options_tag(&self) -> bool {
+        debug!("Usage::needs_options_tag");
+        'outer: for f in self.cmd.get_non_positionals() {
+            debug!("Usage::needs_options_tag:iter: f={}", f.name);
+
+            // Don't print `[OPTIONS]` just for help or version
+            if f.long == Some("help") || f.long == Some("version") {
+                debug!("Usage::needs_options_tag:iter Option is built-in");
+                continue;
+            }
+
+            if f.is_hide_set() {
+                debug!("Usage::needs_options_tag:iter Option is hidden");
+                continue;
+            }
+            if f.is_required_set() {
+                debug!("Usage::needs_options_tag:iter Option is required");
+                continue;
+            }
+            for grp_s in self.cmd.groups_for_arg(&f.id) {
+                debug!("Usage::needs_options_tag:iter:iter: grp_s={:?}", grp_s);
+                if self.cmd.get_groups().any(|g| g.id == grp_s && g.required) {
+                    debug!("Usage::needs_options_tag:iter:iter: Group is required");
+                    continue 'outer;
+                }
+            }
+
+            debug!("Usage::needs_options_tag:iter: [OPTIONS] required");
+            return true;
+        }
+
+        debug!("Usage::needs_options_tag: [OPTIONS] not required");
+        false
+    }
+
+    // Returns the required args in usage string form by fully unrolling all groups
+    // `incl_last`: should we include args that are Arg::Last? (i.e. `prog [foo] -- [last]). We
+    // can't do that for required usages being built for subcommands because it would look like:
+    // `prog [foo] -- [last] <subcommand>` which is totally wrong.
+    pub(crate) fn get_required_usage_from(
+        &self,
+        incls: &[Id],
+        matcher: Option<&ArgMatcher>,
+        incl_last: bool,
+    ) -> IndexSet<String> {
+        debug!(
+            "Usage::get_required_usage_from: incls={:?}, matcher={:?}, incl_last={:?}",
+            incls,
+            matcher.is_some(),
+            incl_last
+        );
+        let mut ret_val = IndexSet::new();
+
+        let mut unrolled_reqs = IndexSet::new();
+
+        let required_owned;
+        let required = if let Some(required) = self.required {
+            required
+        } else {
+            required_owned = self.cmd.required_graph();
+            &required_owned
+        };
+
+        for a in required.iter() {
+            let is_relevant = |(val, req_arg): &(ArgPredicate<'_>, Id)| -> Option<Id> {
+                let required = match val {
+                    ArgPredicate::Equals(_) => {
+                        if let Some(matcher) = matcher {
+                            matcher.check_explicit(a, *val)
+                        } else {
+                            false
+                        }
+                    }
+                    ArgPredicate::IsPresent => true,
+                };
+                required.then(|| req_arg.clone())
+            };
+
+            for aa in self.cmd.unroll_arg_requires(is_relevant, a) {
+                // if we don't check for duplicates here this causes duplicate error messages
+                // see https://github.com/clap-rs/clap/issues/2770
+                unrolled_reqs.insert(aa);
+            }
+            // always include the required arg itself. it will not be enumerated
+            // by unroll_requirements_for_arg.
+            unrolled_reqs.insert(a.clone());
+        }
+
+        debug!(
+            "Usage::get_required_usage_from: unrolled_reqs={:?}",
+            unrolled_reqs
+        );
+
+        let mut required_groups_members = IndexSet::new();
+        let mut required_opts = IndexSet::new();
+        let mut required_groups = IndexSet::new();
+        let mut required_positionals = Vec::new();
+        for req in unrolled_reqs.iter().chain(incls.iter()) {
+            if let Some(arg) = self.cmd.find(req) {
+                let is_present = matcher
+                    .map(|m| m.check_explicit(req, ArgPredicate::IsPresent))
+                    .unwrap_or(false);
+                debug!(
+                    "Usage::get_required_usage_from:iter:{:?} arg is_present={}",
+                    req, is_present
+                );
+                if !is_present {
+                    if arg.is_positional() {
+                        if incl_last || !arg.is_last_set() {
+                            required_positionals.push((arg.index.unwrap(), arg.to_string()));
+                        }
+                    } else {
+                        required_opts.insert(arg.to_string());
+                    }
+                }
+            } else {
+                debug_assert!(self.cmd.find_group(req).is_some());
+                let group_members = self.cmd.unroll_args_in_group(req);
+                let is_present = matcher
+                    .map(|m| {
+                        group_members
+                            .iter()
+                            .any(|arg| m.check_explicit(arg, ArgPredicate::IsPresent))
+                    })
+                    .unwrap_or(false);
+                debug!(
+                    "Usage::get_required_usage_from:iter:{:?} group is_present={}",
+                    req, is_present
+                );
+                if !is_present {
+                    let elem = self.cmd.format_group(req);
+                    required_groups.insert(elem);
+                    required_groups_members.extend(
+                        group_members
+                            .iter()
+                            .flat_map(|id| self.cmd.find(id))
+                            .map(|arg| arg.to_string()),
+                    );
+                }
+            }
+        }
+
+        required_opts.retain(|arg| !required_groups_members.contains(arg));
+        ret_val.extend(required_opts);
+
+        ret_val.extend(required_groups);
+
+        required_positionals.sort_by_key(|(ind, _)| *ind); // sort by index
+        for (_, p) in required_positionals {
+            if !required_groups_members.contains(&p) {
+                ret_val.insert(p);
+            }
+        }
+
+        debug!("Usage::get_required_usage_from: ret_val={:?}", ret_val);
+        ret_val
+    }
+}
diff --git a/vendor/clap-3.2.20/src/parser/arg_matcher.rs b/vendor/clap-3.2.20/src/parser/arg_matcher.rs
new file mode 100644
index 000000000..22087e722
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/arg_matcher.rs
@@ -0,0 +1,280 @@
+// Std
+use std::collections::HashMap;
+use std::ffi::OsString;
+use std::mem;
+use std::ops::Deref;
+
+// Internal
+use crate::builder::{Arg, ArgPredicate, Command};
+use crate::parser::AnyValue;
+use crate::parser::Identifier;
+use crate::parser::PendingArg;
+use crate::parser::{ArgMatches, MatchedArg, SubCommand, ValueSource};
+use crate::util::Id;
+use crate::INTERNAL_ERROR_MSG;
+
+#[derive(Debug, Default)]
+pub(crate) struct ArgMatcher {
+    matches: ArgMatches,
+    pending: Option<PendingArg>,
+}
+
+impl ArgMatcher {
+    pub(crate) fn new(_cmd: &Command) -> Self {
+        ArgMatcher {
+            matches: ArgMatches {
+                #[cfg(debug_assertions)]
+                valid_args: {
+                    let args = _cmd.get_arguments().map(|a| a.id.clone());
+                    let groups = _cmd.get_groups().map(|g| g.id.clone());
+                    args.chain(groups).collect()
+                },
+                #[cfg(debug_assertions)]
+                valid_subcommands: _cmd.get_subcommands().map(|sc| sc.get_id()).collect(),
+                // HACK: Allow an external subcommand's ArgMatches be a stand-in for any ArgMatches
+                // since users can't detect it and avoid the asserts.
+                //
+                // See clap-rs/clap#3263
+                #[cfg(debug_assertions)]
+                #[cfg(not(feature = "unstable-v4"))]
+                disable_asserts: _cmd.is_allow_external_subcommands_set(),
+                #[cfg(debug_assertions)]
+                #[cfg(feature = "unstable-v4")]
+                disable_asserts: false,
+                ..Default::default()
+            },
+            pending: None,
+        }
+    }
+
+    pub(crate) fn into_inner(self) -> ArgMatches {
+        self.matches
+    }
+
+    pub(crate) fn propagate_globals(&mut self, global_arg_vec: &[Id]) {
+        debug!(
+            "ArgMatcher::get_global_values: global_arg_vec={:?}",
+            global_arg_vec
+        );
+        let mut vals_map = HashMap::new();
+        self.fill_in_global_values(global_arg_vec, &mut vals_map);
+    }
+
+    fn fill_in_global_values(
+        &mut self,
+        global_arg_vec: &[Id],
+        vals_map: &mut HashMap<Id, MatchedArg>,
+    ) {
+        for global_arg in global_arg_vec {
+            if let Some(ma) = self.get(global_arg) {
+                // We have to check if the parent's global arg wasn't used but still exists
+                // such as from a default value.
+                //
+                // For example, `myprog subcommand --global-arg=value` where `--global-arg` defines
+                // a default value of `other` myprog would have an existing MatchedArg for
+                // `--global-arg` where the value is `other`
+                let to_update = if let Some(parent_ma) = vals_map.get(global_arg) {
+                    if parent_ma.source() > ma.source() {
+                        parent_ma
+                    } else {
+                        ma
+                    }
+                } else {
+                    ma
+                }
+                .clone();
+                vals_map.insert(global_arg.clone(), to_update);
+            }
+        }
+        if let Some(ref mut sc) = self.matches.subcommand {
+            let mut am = ArgMatcher {
+                matches: mem::take(&mut sc.matches),
+                pending: None,
+            };
+            am.fill_in_global_values(global_arg_vec, vals_map);
+            mem::swap(&mut am.matches, &mut sc.matches);
+        }
+
+        for (name, matched_arg) in vals_map.iter_mut() {
+            self.matches.args.insert(name.clone(), matched_arg.clone());
+        }
+    }
+
+    pub(crate) fn get(&self, arg: &Id) -> Option<&MatchedArg> {
+        self.matches.args.get(arg)
+    }
+
+    pub(crate) fn get_mut(&mut self, arg: &Id) -> Option<&mut MatchedArg> {
+        self.matches.args.get_mut(arg)
+    }
+
+    pub(crate) fn remove(&mut self, arg: &Id) {
+        self.matches.args.swap_remove(arg);
+    }
+
+    pub(crate) fn contains(&self, arg: &Id) -> bool {
+        self.matches.args.contains_key(arg)
+    }
+
+    pub(crate) fn arg_ids(&self) -> indexmap::map::Keys<Id, MatchedArg> {
+        self.matches.args.keys()
+    }
+
+    pub(crate) fn entry(&mut self, arg: &Id) -> indexmap::map::Entry<Id, MatchedArg> {
+        self.matches.args.entry(arg.clone())
+    }
+
+    pub(crate) fn subcommand(&mut self, sc: SubCommand) {
+        self.matches.subcommand = Some(Box::new(sc));
+    }
+
+    pub(crate) fn subcommand_name(&self) -> Option<&str> {
+        self.matches.subcommand_name()
+    }
+
+    pub(crate) fn iter(&self) -> indexmap::map::Iter<Id, MatchedArg> {
+        self.matches.args.iter()
+    }
+
+    pub(crate) fn check_explicit<'a>(&self, arg: &Id, predicate: ArgPredicate<'a>) -> bool {
+        self.get(arg).map_or(false, |a| a.check_explicit(predicate))
+    }
+
+    pub(crate) fn start_custom_arg(&mut self, arg: &Arg, source: ValueSource) {
+        let id = &arg.id;
+        debug!(
+            "ArgMatcher::start_custom_arg: id={:?}, source={:?}",
+            id, source
+        );
+        let ma = self.entry(id).or_insert(MatchedArg::new_arg(arg));
+        debug_assert_eq!(ma.type_id(), Some(arg.get_value_parser().type_id()));
+        ma.set_source(source);
+        ma.new_val_group();
+    }
+
+    pub(crate) fn start_custom_group(&mut self, id: &Id, source: ValueSource) {
+        debug!(
+            "ArgMatcher::start_custom_arg: id={:?}, source={:?}",
+            id, source
+        );
+        let ma = self.entry(id).or_insert(MatchedArg::new_group());
+        debug_assert_eq!(ma.type_id(), None);
+        ma.set_source(source);
+        ma.new_val_group();
+    }
+
+    pub(crate) fn start_occurrence_of_arg(&mut self, arg: &Arg) {
+        let id = &arg.id;
+        debug!("ArgMatcher::start_occurrence_of_arg: id={:?}", id);
+        let ma = self.entry(id).or_insert(MatchedArg::new_arg(arg));
+        debug_assert_eq!(ma.type_id(), Some(arg.get_value_parser().type_id()));
+        ma.set_source(ValueSource::CommandLine);
+        #[allow(deprecated)]
+        ma.inc_occurrences();
+        ma.new_val_group();
+    }
+
+    pub(crate) fn start_occurrence_of_group(&mut self, id: &Id) {
+        debug!("ArgMatcher::start_occurrence_of_group: id={:?}", id);
+        let ma = self.entry(id).or_insert(MatchedArg::new_group());
+        debug_assert_eq!(ma.type_id(), None);
+        ma.set_source(ValueSource::CommandLine);
+        #[allow(deprecated)]
+        ma.inc_occurrences();
+        ma.new_val_group();
+    }
+
+    pub(crate) fn start_occurrence_of_external(&mut self, cmd: &crate::Command) {
+        let id = &Id::empty_hash();
+        debug!("ArgMatcher::start_occurrence_of_external: id={:?}", id,);
+        let ma = self.entry(id).or_insert(MatchedArg::new_external(cmd));
+        debug_assert_eq!(
+            ma.type_id(),
+            Some(
+                cmd.get_external_subcommand_value_parser()
+                    .expect(INTERNAL_ERROR_MSG)
+                    .type_id()
+            )
+        );
+        ma.set_source(ValueSource::CommandLine);
+        #[allow(deprecated)]
+        ma.inc_occurrences();
+        ma.new_val_group();
+    }
+
+    pub(crate) fn add_val_to(&mut self, arg: &Id, val: AnyValue, raw_val: OsString) {
+        let ma = self.get_mut(arg).expect(INTERNAL_ERROR_MSG);
+        ma.append_val(val, raw_val);
+    }
+
+    pub(crate) fn add_index_to(&mut self, arg: &Id, idx: usize) {
+        let ma = self.get_mut(arg).expect(INTERNAL_ERROR_MSG);
+        ma.push_index(idx);
+    }
+
+    pub(crate) fn needs_more_vals(&self, o: &Arg) -> bool {
+        let num_resolved = self.get(&o.id).map(|ma| ma.num_vals()).unwrap_or(0);
+        let num_pending = self
+            .pending
+            .as_ref()
+            .and_then(|p| (p.id == o.id).then(|| p.raw_vals.len()))
+            .unwrap_or(0);
+        let current_num = num_resolved + num_pending;
+        debug!(
+            "ArgMatcher::needs_more_vals: o={}, resolved={}, pending={}",
+            o.name, num_resolved, num_pending
+        );
+        if current_num == 0 {
+            true
+        } else if let Some(num) = o.num_vals {
+            debug!("ArgMatcher::needs_more_vals: num_vals...{}", num);
+            #[allow(deprecated)]
+            if o.is_multiple_occurrences_set() {
+                (current_num % num) != 0
+            } else {
+                num != current_num
+            }
+        } else if let Some(num) = o.max_vals {
+            debug!("ArgMatcher::needs_more_vals: max_vals...{}", num);
+            current_num < num
+        } else if o.min_vals.is_some() {
+            debug!("ArgMatcher::needs_more_vals: min_vals...true");
+            true
+        } else {
+            o.is_multiple_values_set()
+        }
+    }
+
+    pub(crate) fn pending_arg_id(&self) -> Option<&Id> {
+        self.pending.as_ref().map(|p| &p.id)
+    }
+
+    pub(crate) fn pending_values_mut(
+        &mut self,
+        id: &Id,
+        ident: Option<Identifier>,
+    ) -> &mut Vec<OsString> {
+        let pending = self.pending.get_or_insert_with(|| PendingArg {
+            id: id.clone(),
+            ident,
+            raw_vals: Default::default(),
+        });
+        debug_assert_eq!(pending.id, *id, "{}", INTERNAL_ERROR_MSG);
+        if ident.is_some() {
+            debug_assert_eq!(pending.ident, ident, "{}", INTERNAL_ERROR_MSG);
+        }
+        &mut pending.raw_vals
+    }
+
+    pub(crate) fn take_pending(&mut self) -> Option<PendingArg> {
+        self.pending.take()
+    }
+}
+
+impl Deref for ArgMatcher {
+    type Target = ArgMatches;
+
+    fn deref(&self) -> &Self::Target {
+        &self.matches
+    }
+}
diff --git a/vendor/clap-3.2.20/src/parser/error.rs b/vendor/clap-3.2.20/src/parser/error.rs
new file mode 100644
index 000000000..caeba4b8f
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/error.rs
@@ -0,0 +1,67 @@
+use crate::util::Id;
+
+/// Violation of [`ArgMatches`][crate::ArgMatches] assumptions
+#[derive(Clone, Debug)]
+#[allow(missing_copy_implementations)] // We might add non-Copy types in the future
+#[non_exhaustive]
+pub enum MatchesError {
+    /// Failed to downcast `AnyValue` to the specified type
+    #[non_exhaustive]
+    Downcast {
+        /// Type for value stored in [`ArgMatches`][crate::ArgMatches]
+        actual: super::AnyValueId,
+        /// The target type to downcast to
+        expected: super::AnyValueId,
+    },
+    /// Argument not defined in [`Command`][crate::Command]
+    #[non_exhaustive]
+    UnknownArgument {
+        // Missing `id` but blocked on a public id type which will hopefully come with `unstable-v4`
+    },
+}
+
+impl MatchesError {
+    #[track_caller]
+    pub(crate) fn unwrap<T>(id: &Id, r: Result<T, MatchesError>) -> T {
+        let err = match r {
+            Ok(t) => {
+                return t;
+            }
+            Err(err) => err,
+        };
+        panic!(
+            "Mismatch between definition and access of `{:?}`. {}",
+            id, err
+        )
+    }
+}
+
+impl std::error::Error for MatchesError {}
+
+impl std::fmt::Display for MatchesError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match self {
+            Self::Downcast { actual, expected } => {
+                writeln!(
+                    f,
+                    "Could not downcast to {:?}, need to downcast to {:?}",
+                    expected, actual
+                )
+            }
+            Self::UnknownArgument {} => {
+                writeln!(f, "Unknown argument or group id.  Make sure you are using the argument id and not the short or long flags")
+            }
+        }
+    }
+}
+
+#[test]
+fn check_auto_traits() {
+    static_assertions::assert_impl_all!(
+        MatchesError: Send,
+        Sync,
+        std::panic::RefUnwindSafe,
+        std::panic::UnwindSafe,
+        Unpin
+    );
+}
diff --git a/vendor/clap-3.2.20/src/parser/features/mod.rs b/vendor/clap-3.2.20/src/parser/features/mod.rs
new file mode 100644
index 000000000..bdeb766ec
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/features/mod.rs
@@ -0,0 +1 @@
+pub(crate) mod suggestions;
diff --git a/vendor/clap-3.2.20/src/parser/features/suggestions.rs b/vendor/clap-3.2.20/src/parser/features/suggestions.rs
new file mode 100644
index 000000000..9e46f3c9e
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/features/suggestions.rs
@@ -0,0 +1,105 @@
+#[cfg(feature = "suggestions")]
+use std::cmp::Ordering;
+
+// Internal
+use crate::builder::Command;
+
+/// Produces multiple strings from a given list of possible values which are similar
+/// to the passed in value `v` within a certain confidence by least confidence.
+/// Thus in a list of possible values like ["foo", "bar"], the value "fop" will yield
+/// `Some("foo")`, whereas "blark" would yield `None`.
+#[cfg(feature = "suggestions")]
+pub(crate) fn did_you_mean<T, I>(v: &str, possible_values: I) -> Vec<String>
+where
+    T: AsRef<str>,
+    I: IntoIterator<Item = T>,
+{
+    let mut candidates: Vec<(f64, String)> = possible_values
+        .into_iter()
+        .map(|pv| (strsim::jaro_winkler(v, pv.as_ref()), pv.as_ref().to_owned()))
+        .filter(|(confidence, _)| *confidence > 0.8)
+        .collect();
+    candidates.sort_by(|a, b| a.0.partial_cmp(&b.0).unwrap_or(Ordering::Equal));
+    candidates.into_iter().map(|(_, pv)| pv).collect()
+}
+
+#[cfg(not(feature = "suggestions"))]
+pub(crate) fn did_you_mean<T, I>(_: &str, _: I) -> Vec<String>
+where
+    T: AsRef<str>,
+    I: IntoIterator<Item = T>,
+{
+    Vec::new()
+}
+
+/// Returns a suffix that can be empty, or is the standard 'did you mean' phrase
+pub(crate) fn did_you_mean_flag<'a, 'help, I, T>(
+    arg: &str,
+    remaining_args: &[&str],
+    longs: I,
+    subcommands: impl IntoIterator<Item = &'a mut Command<'help>>,
+) -> Option<(String, Option<String>)>
+where
+    'help: 'a,
+    T: AsRef<str>,
+    I: IntoIterator<Item = T>,
+{
+    use crate::mkeymap::KeyType;
+
+    match did_you_mean(arg, longs).pop() {
+        Some(candidate) => Some((candidate, None)),
+        None => subcommands
+            .into_iter()
+            .filter_map(|subcommand| {
+                subcommand._build_self();
+
+                let longs = subcommand.get_keymap().keys().filter_map(|a| {
+                    if let KeyType::Long(v) = a {
+                        Some(v.to_string_lossy().into_owned())
+                    } else {
+                        None
+                    }
+                });
+
+                let subcommand_name = subcommand.get_name();
+
+                let candidate = did_you_mean(arg, longs).pop()?;
+                let score = remaining_args.iter().position(|x| *x == subcommand_name)?;
+                Some((score, (candidate, Some(subcommand_name.to_string()))))
+            })
+            .min_by_key(|(x, _)| *x)
+            .map(|(_, suggestion)| suggestion),
+    }
+}
+
+#[cfg(all(test, features = "suggestions"))]
+mod test {
+    use super::*;
+
+    #[test]
+    fn possible_values_match() {
+        let p_vals = ["test", "possible", "values"];
+        assert_eq!(did_you_mean("tst", p_vals.iter()), Some("test"));
+    }
+
+    #[test]
+    fn possible_values_match() {
+        let p_vals = ["test", "temp"];
+        assert_eq!(did_you_mean("te", p_vals.iter()), Some("test"));
+    }
+
+    #[test]
+    fn possible_values_nomatch() {
+        let p_vals = ["test", "possible", "values"];
+        assert!(did_you_mean("hahaahahah", p_vals.iter()).is_none());
+    }
+
+    #[test]
+    fn flag() {
+        let p_vals = ["test", "possible", "values"];
+        assert_eq!(
+            did_you_mean_flag("tst", p_vals.iter(), []),
+            Some(("test", None))
+        );
+    }
+}
diff --git a/vendor/clap-3.2.20/src/parser/matches/any_value.rs b/vendor/clap-3.2.20/src/parser/matches/any_value.rs
new file mode 100644
index 000000000..a9277e75f
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/matches/any_value.rs
@@ -0,0 +1,112 @@
+#[derive(Clone)]
+pub(crate) struct AnyValue {
+    inner: std::sync::Arc<dyn std::any::Any + Send + Sync + 'static>,
+    // While we can extract `TypeId` from `inner`, the debug repr is of a number, so let's track
+    // the type_name in debug builds.
+    id: AnyValueId,
+}
+
+impl AnyValue {
+    pub(crate) fn new<V: std::any::Any + Clone + Send + Sync + 'static>(inner: V) -> Self {
+        let id = AnyValueId::of::<V>();
+        let inner = std::sync::Arc::new(inner);
+        Self { inner, id }
+    }
+
+    pub(crate) fn downcast_ref<T: std::any::Any + Clone + Send + Sync + 'static>(
+        &self,
+    ) -> Option<&T> {
+        self.inner.downcast_ref::<T>()
+    }
+
+    pub(crate) fn downcast_into<T: std::any::Any + Clone + Send + Sync>(self) -> Result<T, Self> {
+        let id = self.id;
+        let value =
+            std::sync::Arc::downcast::<T>(self.inner).map_err(|inner| Self { inner, id })?;
+        let value = std::sync::Arc::try_unwrap(value).unwrap_or_else(|arc| (*arc).clone());
+        Ok(value)
+    }
+
+    pub(crate) fn type_id(&self) -> AnyValueId {
+        self.id
+    }
+}
+
+impl std::fmt::Debug for AnyValue {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
+        f.debug_struct("AnyValue").field("inner", &self.id).finish()
+    }
+}
+
+#[derive(Copy, Clone)]
+pub struct AnyValueId {
+    type_id: std::any::TypeId,
+    #[cfg(debug_assertions)]
+    type_name: &'static str,
+}
+
+impl AnyValueId {
+    pub(crate) fn of<A: ?Sized + 'static>() -> Self {
+        Self {
+            type_id: std::any::TypeId::of::<A>(),
+            #[cfg(debug_assertions)]
+            type_name: std::any::type_name::<A>(),
+        }
+    }
+}
+
+impl PartialEq for AnyValueId {
+    fn eq(&self, other: &Self) -> bool {
+        self.type_id == other.type_id
+    }
+}
+
+impl Eq for AnyValueId {}
+
+impl PartialOrd for AnyValueId {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        self.type_id.partial_cmp(&other.type_id)
+    }
+}
+
+impl Ord for AnyValueId {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.type_id.cmp(&other.type_id)
+    }
+}
+
+impl std::hash::Hash for AnyValueId {
+    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
+        self.type_id.hash(state);
+    }
+}
+
+impl std::fmt::Debug for AnyValueId {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
+        #[cfg(not(debug_assertions))]
+        {
+            self.type_id.fmt(f)
+        }
+        #[cfg(debug_assertions)]
+        {
+            f.debug_struct(self.type_name).finish()
+        }
+    }
+}
+
+impl<'a, A: ?Sized + 'static> From<&'a A> for AnyValueId {
+    fn from(_: &'a A) -> Self {
+        Self::of::<A>()
+    }
+}
+
+#[cfg(test)]
+mod test {
+    #[test]
+    #[cfg(debug_assertions)]
+    fn debug_impl() {
+        use super::*;
+
+        assert_eq!(format!("{:?}", AnyValue::new(5)), "AnyValue { inner: i32 }");
+    }
+}
diff --git a/vendor/clap-3.2.20/src/parser/matches/arg_matches.rs b/vendor/clap-3.2.20/src/parser/matches/arg_matches.rs
new file mode 100644
index 000000000..2585c0219
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/matches/arg_matches.rs
@@ -0,0 +1,1896 @@
+// Std
+use std::any::Any;
+use std::borrow::Cow;
+use std::ffi::{OsStr, OsString};
+use std::fmt::{Debug, Display};
+use std::iter::{Cloned, Flatten, Map};
+use std::slice::Iter;
+use std::str::FromStr;
+
+// Third Party
+use indexmap::IndexMap;
+
+// Internal
+use crate::parser::AnyValue;
+use crate::parser::AnyValueId;
+use crate::parser::MatchedArg;
+use crate::parser::MatchesError;
+use crate::parser::ValueSource;
+use crate::util::{Id, Key};
+use crate::Error;
+use crate::INTERNAL_ERROR_MSG;
+
+/// Container for parse results.
+///
+/// Used to get information about the arguments that were supplied to the program at runtime by
+/// the user. New instances of this struct are obtained by using the [`Command::get_matches`] family of
+/// methods.
+///
+/// # Examples
+///
+/// ```no_run
+/// # use clap::{Command, Arg, ValueSource};
+/// let matches = Command::new("MyApp")
+///     .arg(Arg::new("out")
+///         .long("output")
+///         .required(true)
+///         .takes_value(true)
+///         .default_value("-"))
+///     .arg(Arg::new("cfg")
+///         .short('c')
+///         .takes_value(true))
+///     .get_matches(); // builds the instance of ArgMatches
+///
+/// // to get information about the "cfg" argument we created, such as the value supplied we use
+/// // various ArgMatches methods, such as [ArgMatches::get_one]
+/// if let Some(c) = matches.get_one::<String>("cfg") {
+///     println!("Value for -c: {}", c);
+/// }
+///
+/// // The ArgMatches::get_one method returns an Option because the user may not have supplied
+/// // that argument at runtime. But if we specified that the argument was "required" as we did
+/// // with the "out" argument, we can safely unwrap because `clap` verifies that was actually
+/// // used at runtime.
+/// println!("Value for --output: {}", matches.get_one::<String>("out").unwrap());
+///
+/// // You can check the presence of an argument's values
+/// if matches.contains_id("out") {
+///     // However, if you want to know where the value came from
+///     if matches.value_source("out").expect("checked contains_id") == ValueSource::CommandLine {
+///         println!("`out` set by user");
+///     } else {
+///         println!("`out` is defaulted");
+///     }
+/// }
+/// ```
+/// [`Command::get_matches`]: crate::Command::get_matches()
+#[derive(Debug, Clone, Default, PartialEq, Eq)]
+pub struct ArgMatches {
+    #[cfg(debug_assertions)]
+    pub(crate) valid_args: Vec<Id>,
+    #[cfg(debug_assertions)]
+    pub(crate) valid_subcommands: Vec<Id>,
+    #[cfg(debug_assertions)]
+    pub(crate) disable_asserts: bool,
+    pub(crate) args: IndexMap<Id, MatchedArg>,
+    pub(crate) subcommand: Option<Box<SubCommand>>,
+}
+
+/// # Arguments
+impl ArgMatches {
+    /// Gets the value of a specific option or positional argument.
+    ///
+    /// i.e. an argument that [takes an additional value][crate::Arg::takes_value] at runtime.
+    ///
+    /// Returns an error if the wrong type was used.
+    ///
+    /// Returns `None` if the option wasn't present.
+    ///
+    /// *NOTE:* This will always return `Some(value)` if [`default_value`] has been set.
+    /// [`ArgMatches::value_source`] can be used to check if a value is present at runtime.
+    ///
+    /// # Panic
+    ///
+    /// If the argument definition and access mismatch.  To handle this case programmatically, see
+    /// [`ArgMatches::try_get_one`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, value_parser};
+    /// let m = Command::new("myapp")
+    ///     .arg(Arg::new("port")
+    ///         .value_parser(value_parser!(usize))
+    ///         .takes_value(true)
+    ///         .required(true))
+    ///     .get_matches_from(vec!["myapp", "2020"]);
+    ///
+    /// let port: usize = *m
+    ///     .get_one("port")
+    ///     .expect("`port`is required");
+    /// assert_eq!(port, 2020);
+    /// ```
+    /// [option]: crate::Arg::takes_value()
+    /// [positional]: crate::Arg::index()
+    /// [`default_value`]: crate::Arg::default_value()
+    #[track_caller]
+    pub fn get_one<T: Any + Clone + Send + Sync + 'static>(&self, id: &str) -> Option<&T> {
+        let internal_id = Id::from(id);
+        MatchesError::unwrap(&internal_id, self.try_get_one(id))
+    }
+
+    /// Gets the value of a specific [`ArgAction::Count`][crate::ArgAction::Count] flag
+    ///
+    /// # Panic
+    ///
+    /// If the argument's action is not [`ArgAction::Count`][crate::ArgAction::Count]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .arg(
+    ///         Arg::new("flag")
+    ///             .long("flag")
+    ///             .action(clap::ArgAction::Count)
+    ///     );
+    ///
+    /// let matches = cmd.clone().try_get_matches_from(["mycmd", "--flag", "--flag"]).unwrap();
+    /// assert_eq!(
+    ///     matches.get_count("flag"),
+    ///     2
+    /// );
+    /// ```
+    #[track_caller]
+    pub fn get_count(&self, id: &str) -> u8 {
+        *self
+            .get_one::<u8>(id)
+            .expect("ArgAction::Count is defaulted")
+    }
+
+    /// Gets the value of a specific [`ArgAction::SetTrue`][crate::ArgAction::SetTrue] or [`ArgAction::SetFalse`][crate::ArgAction::SetFalse] flag
+    ///
+    /// # Panic
+    ///
+    /// If the argument's action is not [`ArgAction::SetTrue`][crate::ArgAction::SetTrue] or [`ArgAction::SetFalse`][crate::ArgAction::SetFalse]
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// # use clap::Arg;
+    /// let cmd = Command::new("mycmd")
+    ///     .arg(
+    ///         Arg::new("flag")
+    ///             .long("flag")
+    ///             .action(clap::ArgAction::SetTrue)
+    ///     );
+    ///
+    /// let matches = cmd.clone().try_get_matches_from(["mycmd", "--flag", "--flag"]).unwrap();
+    /// assert!(matches.contains_id("flag"));
+    /// assert_eq!(
+    ///     matches.get_flag("flag"),
+    ///     true
+    /// );
+    /// ```
+    #[track_caller]
+    pub fn get_flag(&self, id: &str) -> bool {
+        *self
+            .get_one::<bool>(id)
+            .expect("ArgAction::SetTrue / ArgAction::SetFalse is defaulted")
+    }
+
+    /// Iterate over values of a specific option or positional argument.
+    ///
+    /// i.e. an argument that takes multiple values at runtime.
+    ///
+    /// Returns an error if the wrong type was used.
+    ///
+    /// Returns `None` if the option wasn't present.
+    ///
+    /// # Panic
+    ///
+    /// If the argument definition and access mismatch.  To handle this case programmatically, see
+    /// [`ArgMatches::try_get_many`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, value_parser, ArgAction};
+    /// let m = Command::new("myprog")
+    ///     .arg(Arg::new("ports")
+    ///         .action(ArgAction::Append)
+    ///         .value_parser(value_parser!(usize))
+    ///         .short('p')
+    ///         .takes_value(true)
+    ///         .required(true))
+    ///     .get_matches_from(vec![
+    ///         "myprog", "-p", "22", "-p", "80", "-p", "2020"
+    ///     ]);
+    /// let vals: Vec<usize> = m.get_many("ports")
+    ///     .expect("`port`is required")
+    ///     .copied()
+    ///     .collect();
+    /// assert_eq!(vals, [22, 80, 2020]);
+    /// ```
+    #[track_caller]
+    pub fn get_many<T: Any + Clone + Send + Sync + 'static>(
+        &self,
+        id: &str,
+    ) -> Option<ValuesRef<T>> {
+        let internal_id = Id::from(id);
+        MatchesError::unwrap(&internal_id, self.try_get_many(id))
+    }
+
+    /// Iterate over the original argument values.
+    ///
+    /// An `OsStr` on Unix-like systems is any series of bytes, regardless of whether or not they
+    /// contain valid UTF-8. Since [`String`]s in Rust are guaranteed to be valid UTF-8, a valid
+    /// filename on a Unix system as an argument value may contain invalid UTF-8.
+    ///
+    /// Returns `None` if the option wasn't present.
+    ///
+    /// # Panic
+    ///
+    /// If the argument definition and access mismatch.  To handle this case programmatically, see
+    /// [`ArgMatches::try_get_raw`].
+    ///
+    /// # Examples
+    ///
+    #[cfg_attr(not(unix), doc = " ```ignore")]
+    #[cfg_attr(unix, doc = " ```")]
+    /// # use clap::{Command, arg, value_parser};
+    /// # use std::ffi::{OsStr,OsString};
+    /// # use std::os::unix::ffi::{OsStrExt,OsStringExt};
+    /// use std::path::PathBuf;
+    ///
+    /// let m = Command::new("utf8")
+    ///     .arg(arg!(<arg> ... "some arg").value_parser(value_parser!(PathBuf)))
+    ///     .get_matches_from(vec![OsString::from("myprog"),
+    ///                                 // "Hi"
+    ///                                 OsString::from_vec(vec![b'H', b'i']),
+    ///                                 // "{0xe9}!"
+    ///                                 OsString::from_vec(vec![0xe9, b'!'])]);
+    ///
+    /// let mut itr = m.get_raw("arg")
+    ///     .expect("`port`is required")
+    ///     .into_iter();
+    /// assert_eq!(itr.next(), Some(OsStr::new("Hi")));
+    /// assert_eq!(itr.next(), Some(OsStr::from_bytes(&[0xe9, b'!'])));
+    /// assert_eq!(itr.next(), None);
+    /// ```
+    /// [`Iterator`]: std::iter::Iterator
+    /// [`OsSt`]: std::ffi::OsStr
+    /// [values]: OsValues
+    /// [`String`]: std::string::String
+    #[track_caller]
+    pub fn get_raw(&self, id: &str) -> Option<RawValues<'_>> {
+        let internal_id = Id::from(id);
+        MatchesError::unwrap(&internal_id, self.try_get_raw(id))
+    }
+
+    /// Returns the value of a specific option or positional argument.
+    ///
+    /// i.e. an argument that [takes an additional value][crate::Arg::takes_value] at runtime.
+    ///
+    /// Returns an error if the wrong type was used.  No item will have been removed.
+    ///
+    /// Returns `None` if the option wasn't present.
+    ///
+    /// *NOTE:* This will always return `Some(value)` if [`default_value`] has been set.
+    /// [`ArgMatches::value_source`] can be used to check if a value is present at runtime.
+    ///
+    /// # Panic
+    ///
+    /// If the argument definition and access mismatch.  To handle this case programmatically, see
+    /// [`ArgMatches::try_remove_one`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, value_parser};
+    /// let mut m = Command::new("myprog")
+    ///     .arg(Arg::new("file")
+    ///         .required(true)
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec![
+    ///         "myprog", "file.txt",
+    ///     ]);
+    /// let vals: String = m.remove_one("file")
+    ///     .expect("`file`is required");
+    /// assert_eq!(vals, "file.txt");
+    /// ```
+    /// [option]: crate::Arg::takes_value()
+    /// [positional]: crate::Arg::index()
+    /// [`default_value`]: crate::Arg::default_value()
+    #[track_caller]
+    pub fn remove_one<T: Any + Clone + Send + Sync + 'static>(&mut self, id: &str) -> Option<T> {
+        let internal_id = Id::from(id);
+        MatchesError::unwrap(&internal_id, self.try_remove_one(id))
+    }
+
+    /// Return values of a specific option or positional argument.
+    ///
+    /// i.e. an argument that takes multiple values at runtime.
+    ///
+    /// Returns an error if the wrong type was used.  No item will have been removed.
+    ///
+    /// Returns `None` if the option wasn't present.
+    ///
+    /// # Panic
+    ///
+    /// If the argument definition and access mismatch.  To handle this case programmatically, see
+    /// [`ArgMatches::try_remove_many`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, value_parser, ArgAction};
+    /// let mut m = Command::new("myprog")
+    ///     .arg(Arg::new("file")
+    ///         .action(ArgAction::Append)
+    ///         .multiple_values(true)
+    ///         .required(true)
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec![
+    ///         "myprog", "file1.txt", "file2.txt", "file3.txt", "file4.txt",
+    ///     ]);
+    /// let vals: Vec<String> = m.remove_many("file")
+    ///     .expect("`file`is required")
+    ///     .collect();
+    /// assert_eq!(vals, ["file1.txt", "file2.txt", "file3.txt", "file4.txt"]);
+    /// ```
+    #[track_caller]
+    pub fn remove_many<T: Any + Clone + Send + Sync + 'static>(
+        &mut self,
+        id: &str,
+    ) -> Option<Values2<T>> {
+        let internal_id = Id::from(id);
+        MatchesError::unwrap(&internal_id, self.try_remove_many(id))
+    }
+
+    /// Check if values are present for the argument or group id
+    ///
+    /// *NOTE:* This will always return `true` if [`default_value`] has been set.
+    /// [`ArgMatches::value_source`] can be used to check if a value is present at runtime.
+    ///
+    /// # Panics
+    ///
+    /// If `id` is is not a valid argument or group name.  To handle this case programmatically, see
+    /// [`ArgMatches::try_contains_id`].
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myprog")
+    ///     .arg(Arg::new("debug")
+    ///         .short('d'))
+    ///     .get_matches_from(vec![
+    ///         "myprog", "-d"
+    ///     ]);
+    ///
+    /// assert!(m.contains_id("debug"));
+    /// ```
+    ///
+    /// [`default_value`]: crate::Arg::default_value()
+    pub fn contains_id(&self, id: &str) -> bool {
+        let internal_id = Id::from(id);
+        MatchesError::unwrap(&internal_id, self.try_contains_id(id))
+    }
+
+    /// Check if any args were present on the command line
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let mut cmd = Command::new("myapp")
+    ///     .arg(Arg::new("output")
+    ///         .takes_value(true));
+    ///
+    /// let m = cmd
+    ///     .try_get_matches_from_mut(vec!["myapp", "something"])
+    ///     .unwrap();
+    /// assert!(m.args_present());
+    ///
+    /// let m = cmd
+    ///     .try_get_matches_from_mut(vec!["myapp"])
+    ///     .unwrap();
+    /// assert!(! m.args_present());
+    pub fn args_present(&self) -> bool {
+        !self.args.is_empty()
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_one()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_one()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn value_of<T: Key>(&self, id: T) -> Option<&str> {
+        let id = Id::from(id);
+        let arg = self.get_arg(&id)?;
+        let v = unwrap_string_arg(&id, arg.first()?);
+        Some(v)
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_one()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_one()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn value_of_lossy<T: Key>(&self, id: T) -> Option<Cow<'_, str>> {
+        let id = Id::from(id);
+        let arg = self.get_arg(&id)?;
+        let v = unwrap_os_string_arg(&id, arg.first()?);
+        Some(v.to_string_lossy())
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_one()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_one()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn value_of_os<T: Key>(&self, id: T) -> Option<&OsStr> {
+        let id = Id::from(id);
+        let arg = self.get_arg(&id)?;
+        let v = unwrap_os_string_arg(&id, arg.first()?);
+        Some(v)
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_many()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_many()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn values_of<T: Key>(&self, id: T) -> Option<Values> {
+        #![allow(deprecated)]
+        let id = Id::from(id);
+        let arg = self.get_arg(&id)?;
+        let v = Values {
+            iter: arg.vals_flatten().map(unwrap_string),
+            len: arg.num_vals(),
+        };
+        Some(v)
+    }
+
+    /// Get an [`Iterator`] over groups of values of a specific option.
+    ///
+    /// specifically grouped by the occurrences of the options.
+    ///
+    /// Each group is a `Vec<&str>` containing the arguments passed to a single occurrence
+    /// of the option.
+    ///
+    /// If the option doesn't support multiple occurrences, or there was only a single occurrence,
+    /// the iterator will only contain a single item.
+    ///
+    /// Returns `None` if the option wasn't present.
+    ///
+    /// # Panics
+    ///
+    /// If the value is invalid UTF-8.
+    ///
+    /// If `id` is not a valid argument or group id.
+    ///
+    /// # Examples
+    /// ```rust
+    /// # use clap::{Command,Arg, ArgAction};
+    /// let m = Command::new("myprog")
+    ///     .arg(Arg::new("exec")
+    ///         .short('x')
+    ///         .min_values(1)
+    ///         .action(ArgAction::Append)
+    ///         .value_terminator(";"))
+    ///     .get_matches_from(vec![
+    ///         "myprog", "-x", "echo", "hi", ";", "-x", "echo", "bye"]);
+    /// let vals: Vec<Vec<&str>> = m.grouped_values_of("exec").unwrap().collect();
+    /// assert_eq!(vals, [["echo", "hi"], ["echo", "bye"]]);
+    /// ```
+    /// [`Iterator`]: std::iter::Iterator
+    #[cfg(feature = "unstable-grouped")]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn grouped_values_of<T: Key>(&self, id: T) -> Option<GroupedValues> {
+        let id = Id::from(id);
+        let arg = self.get_arg(&id)?;
+        let v = GroupedValues {
+            iter: arg.vals().map(|g| g.iter().map(unwrap_string).collect()),
+            len: arg.vals().len(),
+        };
+        Some(v)
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_many()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_many()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn values_of_lossy<T: Key>(&self, id: T) -> Option<Vec<String>> {
+        let id = Id::from(id);
+        let arg = self.get_arg(&id)?;
+        let v = arg
+            .vals_flatten()
+            .map(|v| unwrap_os_string_arg(&id, v).to_string_lossy().into_owned())
+            .collect();
+        Some(v)
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_many()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_many()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn values_of_os<T: Key>(&self, id: T) -> Option<OsValues> {
+        #![allow(deprecated)]
+        let id = Id::from(id);
+        let arg = self.get_arg(&id)?;
+        let v = OsValues {
+            iter: arg.vals_flatten().map(unwrap_os_string),
+            len: arg.num_vals(),
+        };
+        Some(v)
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_one()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_one()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn value_of_t<R>(&self, name: &str) -> Result<R, Error>
+    where
+        R: FromStr,
+        <R as FromStr>::Err: Display,
+    {
+        #![allow(deprecated)]
+        let v = self
+            .value_of(name)
+            .ok_or_else(|| Error::argument_not_found_auto(name.to_string()))?;
+        v.parse::<R>().map_err(|e| {
+            let message = format!(
+                "The argument '{}' isn't a valid value for '{}': {}",
+                v, name, e
+            );
+
+            Error::value_validation(name.to_string(), v.to_string(), message.into())
+        })
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_one()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_one()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn value_of_t_or_exit<R>(&self, name: &str) -> R
+    where
+        R: FromStr,
+        <R as FromStr>::Err: Display,
+    {
+        #![allow(deprecated)]
+        self.value_of_t(name).unwrap_or_else(|e| e.exit())
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_many()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_many()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn values_of_t<R>(&self, name: &str) -> Result<Vec<R>, Error>
+    where
+        R: FromStr,
+        <R as FromStr>::Err: Display,
+    {
+        #![allow(deprecated)]
+        let v = self
+            .values_of(name)
+            .ok_or_else(|| Error::argument_not_found_auto(name.to_string()))?;
+        v.map(|v| {
+            v.parse::<R>().map_err(|e| {
+                let message = format!("The argument '{}' isn't a valid value: {}", v, e);
+
+                Error::value_validation(name.to_string(), v.to_string(), message.into())
+            })
+        })
+        .collect()
+    }
+
+    /// Deprecated, replaced with [`ArgMatches::get_many()`]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_many()`")
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn values_of_t_or_exit<R>(&self, name: &str) -> Vec<R>
+    where
+        R: FromStr,
+        <R as FromStr>::Err: Display,
+    {
+        #![allow(deprecated)]
+        self.values_of_t(name).unwrap_or_else(|e| e.exit())
+    }
+
+    /// Deprecated, replaced with [`ArgAction::SetTrue`][crate::ArgAction] or
+    /// [`ArgMatches::contains_id`].
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Replaced with either `ArgAction::SetTrue` or `ArgMatches::contains_id(...)`"
+        )
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn is_present<T: Key>(&self, id: T) -> bool {
+        let id = Id::from(id);
+
+        #[cfg(debug_assertions)]
+        self.get_arg(&id);
+
+        self.args.contains_key(&id)
+    }
+
+    /// Report where argument value came from
+    ///
+    /// # Panics
+    ///
+    /// If `id` is is not a valid argument or group id.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ValueSource};
+    /// let m = Command::new("myprog")
+    ///     .arg(Arg::new("debug")
+    ///         .short('d'))
+    ///     .get_matches_from(vec![
+    ///         "myprog", "-d"
+    ///     ]);
+    ///
+    /// assert_eq!(m.value_source("debug"), Some(ValueSource::CommandLine));
+    /// ```
+    ///
+    /// [`default_value`]: crate::Arg::default_value()
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn value_source<T: Key>(&self, id: T) -> Option<ValueSource> {
+        let id = Id::from(id);
+
+        let value = self.get_arg(&id);
+
+        value.and_then(MatchedArg::source)
+    }
+
+    /// Deprecated, replaced with  [`ArgAction::Count`][crate::ArgAction],
+    /// [`ArgMatches::get_many`]`.len()`, or [`ArgMatches::value_source`].
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(
+            since = "3.2.0",
+            note = "Replaced with either `ArgAction::Count`, `ArgMatches::get_many(...).len()`, or `ArgMatches::value_source`"
+        )
+    )]
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn occurrences_of<T: Key>(&self, id: T) -> u64 {
+        #![allow(deprecated)]
+        self.get_arg(&Id::from(id))
+            .map_or(0, |a| a.get_occurrences())
+    }
+
+    /// The first index of that an argument showed up.
+    ///
+    /// Indices are similar to argv indices, but are not exactly 1:1.
+    ///
+    /// For flags (i.e. those arguments which don't have an associated value), indices refer
+    /// to occurrence of the switch, such as `-f`, or `--flag`. However, for options the indices
+    /// refer to the *values* `-o val` would therefore not represent two distinct indices, only the
+    /// index for `val` would be recorded. This is by design.
+    ///
+    /// Besides the flag/option discrepancy, the primary difference between an argv index and clap
+    /// index, is that clap continues counting once all arguments have properly separated, whereas
+    /// an argv index does not.
+    ///
+    /// The examples should clear this up.
+    ///
+    /// *NOTE:* If an argument is allowed multiple times, this method will only give the *first*
+    /// index.  See [`ArgMatches::indices_of`].
+    ///
+    /// # Panics
+    ///
+    /// If `id` is is not a valid argument or group id.
+    ///
+    /// # Examples
+    ///
+    /// The argv indices are listed in the comments below. See how they correspond to the clap
+    /// indices. Note that if it's not listed in a clap index, this is because it's not saved in
+    /// in an `ArgMatches` struct for querying.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myapp")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("option")
+    ///         .short('o')
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec!["myapp", "-f", "-o", "val"]);
+    ///            // ARGV indices: ^0       ^1    ^2    ^3
+    ///            // clap indices:          ^1          ^3
+    ///
+    /// assert_eq!(m.index_of("flag"), Some(1));
+    /// assert_eq!(m.index_of("option"), Some(3));
+    /// ```
+    ///
+    /// Now notice, if we use one of the other styles of options:
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myapp")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("option")
+    ///         .short('o')
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec!["myapp", "-f", "-o=val"]);
+    ///            // ARGV indices: ^0       ^1    ^2
+    ///            // clap indices:          ^1       ^3
+    ///
+    /// assert_eq!(m.index_of("flag"), Some(1));
+    /// assert_eq!(m.index_of("option"), Some(3));
+    /// ```
+    ///
+    /// Things become much more complicated, or clear if we look at a more complex combination of
+    /// flags. Let's also throw in the final option style for good measure.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myapp")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("flag2")
+    ///         .short('F'))
+    ///     .arg(Arg::new("flag3")
+    ///         .short('z'))
+    ///     .arg(Arg::new("option")
+    ///         .short('o')
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec!["myapp", "-fzF", "-oval"]);
+    ///            // ARGV indices: ^0      ^1       ^2
+    ///            // clap indices:         ^1,2,3    ^5
+    ///            //
+    ///            // clap sees the above as 'myapp -f -z -F -o val'
+    ///            //                         ^0    ^1 ^2 ^3 ^4 ^5
+    /// assert_eq!(m.index_of("flag"), Some(1));
+    /// assert_eq!(m.index_of("flag2"), Some(3));
+    /// assert_eq!(m.index_of("flag3"), Some(2));
+    /// assert_eq!(m.index_of("option"), Some(5));
+    /// ```
+    ///
+    /// One final combination of flags/options to see how they combine:
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myapp")
+    ///     .arg(Arg::new("flag")
+    ///         .short('f'))
+    ///     .arg(Arg::new("flag2")
+    ///         .short('F'))
+    ///     .arg(Arg::new("flag3")
+    ///         .short('z'))
+    ///     .arg(Arg::new("option")
+    ///         .short('o')
+    ///         .takes_value(true))
+    ///     .get_matches_from(vec!["myapp", "-fzFoval"]);
+    ///            // ARGV indices: ^0       ^1
+    ///            // clap indices:          ^1,2,3^5
+    ///            //
+    ///            // clap sees the above as 'myapp -f -z -F -o val'
+    ///            //                         ^0    ^1 ^2 ^3 ^4 ^5
+    /// assert_eq!(m.index_of("flag"), Some(1));
+    /// assert_eq!(m.index_of("flag2"), Some(3));
+    /// assert_eq!(m.index_of("flag3"), Some(2));
+    /// assert_eq!(m.index_of("option"), Some(5));
+    /// ```
+    ///
+    /// The last part to mention is when values are sent in multiple groups with a [delimiter].
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myapp")
+    ///     .arg(Arg::new("option")
+    ///         .short('o')
+    ///         .use_value_delimiter(true)
+    ///         .multiple_values(true))
+    ///     .get_matches_from(vec!["myapp", "-o=val1,val2,val3"]);
+    ///            // ARGV indices: ^0       ^1
+    ///            // clap indices:             ^2   ^3   ^4
+    ///            //
+    ///            // clap sees the above as 'myapp -o val1 val2 val3'
+    ///            //                         ^0    ^1 ^2   ^3   ^4
+    /// assert_eq!(m.index_of("option"), Some(2));
+    /// assert_eq!(m.indices_of("option").unwrap().collect::<Vec<_>>(), &[2, 3, 4]);
+    /// ```
+    /// [delimiter]: crate::Arg::value_delimiter()
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn index_of<T: Key>(&self, id: T) -> Option<usize> {
+        let arg = self.get_arg(&Id::from(id))?;
+        let i = arg.get_index(0)?;
+        Some(i)
+    }
+
+    /// All indices an argument appeared at when parsing.
+    ///
+    /// Indices are similar to argv indices, but are not exactly 1:1.
+    ///
+    /// For flags (i.e. those arguments which don't have an associated value), indices refer
+    /// to occurrence of the switch, such as `-f`, or `--flag`. However, for options the indices
+    /// refer to the *values* `-o val` would therefore not represent two distinct indices, only the
+    /// index for `val` would be recorded. This is by design.
+    ///
+    /// *NOTE:* For more information about how clap indices compared to argv indices, see
+    /// [`ArgMatches::index_of`]
+    ///
+    /// # Panics
+    ///
+    /// If `id` is is not a valid argument or group id.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myapp")
+    ///     .arg(Arg::new("option")
+    ///         .short('o')
+    ///         .use_value_delimiter(true)
+    ///         .multiple_values(true))
+    ///     .get_matches_from(vec!["myapp", "-o=val1,val2,val3"]);
+    ///            // ARGV indices: ^0       ^1
+    ///            // clap indices:             ^2   ^3   ^4
+    ///            //
+    ///            // clap sees the above as 'myapp -o val1 val2 val3'
+    ///            //                         ^0    ^1 ^2   ^3   ^4
+    /// assert_eq!(m.indices_of("option").unwrap().collect::<Vec<_>>(), &[2, 3, 4]);
+    /// ```
+    ///
+    /// Another quick example is when flags and options are used together
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let m = Command::new("myapp")
+    ///     .arg(Arg::new("option")
+    ///         .short('o')
+    ///         .takes_value(true)
+    ///         .action(ArgAction::Append))
+    ///     .arg(Arg::new("flag")
+    ///         .short('f')
+    ///         .action(ArgAction::Count))
+    ///     .get_matches_from(vec!["myapp", "-o", "val1", "-f", "-o", "val2", "-f"]);
+    ///            // ARGV indices: ^0       ^1    ^2      ^3    ^4    ^5      ^6
+    ///            // clap indices:                ^2      ^3          ^5      ^6
+    ///
+    /// assert_eq!(m.indices_of("option").unwrap().collect::<Vec<_>>(), &[2, 5]);
+    /// assert_eq!(m.indices_of("flag").unwrap().collect::<Vec<_>>(), &[6]);
+    /// ```
+    ///
+    /// One final example, which is an odd case; if we *don't* use  value delimiter as we did with
+    /// the first example above instead of `val1`, `val2` and `val3` all being distinc values, they
+    /// would all be a single value of `val1,val2,val3`, in which case they'd only receive a single
+    /// index.
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg};
+    /// let m = Command::new("myapp")
+    ///     .arg(Arg::new("option")
+    ///         .short('o')
+    ///         .takes_value(true)
+    ///         .multiple_values(true))
+    ///     .get_matches_from(vec!["myapp", "-o=val1,val2,val3"]);
+    ///            // ARGV indices: ^0       ^1
+    ///            // clap indices:             ^2
+    ///            //
+    ///            // clap sees the above as 'myapp -o "val1,val2,val3"'
+    ///            //                         ^0    ^1  ^2
+    /// assert_eq!(m.indices_of("option").unwrap().collect::<Vec<_>>(), &[2]);
+    /// ```
+    /// [`ArgMatches::index_of`]: ArgMatches::index_of()
+    /// [delimiter]: Arg::value_delimiter()
+    #[cfg_attr(debug_assertions, track_caller)]
+    pub fn indices_of<T: Key>(&self, id: T) -> Option<Indices<'_>> {
+        let arg = self.get_arg(&Id::from(id))?;
+        let i = Indices {
+            iter: arg.indices(),
+            len: arg.num_vals(),
+        };
+        Some(i)
+    }
+
+    #[inline]
+    #[doc(hidden)]
+    #[cfg_attr(
+        feature = "deprecated",
+        deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::try_get_one()`")
+    )]
+    pub fn is_valid_arg(&self, _id: impl Key) -> bool {
+        #[cfg(debug_assertions)]
+        {
+            let id = Id::from(_id);
+            self.disable_asserts || id == Id::empty_hash() || self.valid_args.contains(&id)
+        }
+        #[cfg(not(debug_assertions))]
+        {
+            true
+        }
+    }
+}
+
+/// # Subcommands
+impl ArgMatches {
+    /// The name and `ArgMatches` of the current [subcommand].
+    ///
+    /// Subcommand values are put in a child [`ArgMatches`]
+    ///
+    /// Returns `None` if the subcommand wasn't present at runtime,
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    ///  let app_m = Command::new("git")
+    ///      .subcommand(Command::new("clone"))
+    ///      .subcommand(Command::new("push"))
+    ///      .subcommand(Command::new("commit"))
+    ///      .get_matches();
+    ///
+    /// match app_m.subcommand() {
+    ///     Some(("clone",  sub_m)) => {}, // clone was used
+    ///     Some(("push",   sub_m)) => {}, // push was used
+    ///     Some(("commit", sub_m)) => {}, // commit was used
+    ///     _                       => {}, // Either no subcommand or one not tested for...
+    /// }
+    /// ```
+    ///
+    /// Another useful scenario is when you want to support third party, or external, subcommands.
+    /// In these cases you can't know the subcommand name ahead of time, so use a variable instead
+    /// with pattern matching!
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// // Assume there is an external subcommand named "subcmd"
+    /// let app_m = Command::new("myprog")
+    ///     .allow_external_subcommands(true)
+    ///     .get_matches_from(vec![
+    ///         "myprog", "subcmd", "--option", "value", "-fff", "--flag"
+    ///     ]);
+    ///
+    /// // All trailing arguments will be stored under the subcommand's sub-matches using an empty
+    /// // string argument name
+    /// match app_m.subcommand() {
+    ///     Some((external, sub_m)) => {
+    ///          let ext_args: Vec<&str> = sub_m.get_many::<String>("")
+    ///             .unwrap().map(|s| s.as_str()).collect();
+    ///          assert_eq!(external, "subcmd");
+    ///          assert_eq!(ext_args, ["--option", "value", "-fff", "--flag"]);
+    ///     },
+    ///     _ => {},
+    /// }
+    /// ```
+    /// [subcommand]: crate::Command::subcommand
+    #[inline]
+    pub fn subcommand(&self) -> Option<(&str, &ArgMatches)> {
+        self.subcommand.as_ref().map(|sc| (&*sc.name, &sc.matches))
+    }
+
+    /// Return the name and `ArgMatches` of the current [subcommand].
+    ///
+    /// Subcommand values are put in a child [`ArgMatches`]
+    ///
+    /// Returns `None` if the subcommand wasn't present at runtime,
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    ///  let mut app_m = Command::new("git")
+    ///      .subcommand(Command::new("clone"))
+    ///      .subcommand(Command::new("push"))
+    ///      .subcommand(Command::new("commit"))
+    ///      .subcommand_required(true)
+    ///      .get_matches();
+    ///
+    /// let (name, sub_m) = app_m.remove_subcommand().expect("required");
+    /// match (name.as_str(), sub_m) {
+    ///     ("clone",  sub_m) => {}, // clone was used
+    ///     ("push",   sub_m) => {}, // push was used
+    ///     ("commit", sub_m) => {}, // commit was used
+    ///     (name, _)         => unimplemented!("{}", name),
+    /// }
+    /// ```
+    ///
+    /// Another useful scenario is when you want to support third party, or external, subcommands.
+    /// In these cases you can't know the subcommand name ahead of time, so use a variable instead
+    /// with pattern matching!
+    ///
+    /// ```rust
+    /// # use clap::Command;
+    /// // Assume there is an external subcommand named "subcmd"
+    /// let mut app_m = Command::new("myprog")
+    ///     .allow_external_subcommands(true)
+    ///     .get_matches_from(vec![
+    ///         "myprog", "subcmd", "--option", "value", "-fff", "--flag"
+    ///     ]);
+    ///
+    /// // All trailing arguments will be stored under the subcommand's sub-matches using an empty
+    /// // string argument name
+    /// match app_m.remove_subcommand() {
+    ///     Some((external, mut sub_m)) => {
+    ///          let ext_args: Vec<String> = sub_m.remove_many("")
+    ///             .expect("`file`is required")
+    ///             .collect();
+    ///          assert_eq!(external, "subcmd");
+    ///          assert_eq!(ext_args, ["--option", "value", "-fff", "--flag"]);
+    ///     },
+    ///     _ => {},
+    /// }
+    /// ```
+    /// [subcommand]: crate::Command::subcommand
+    pub fn remove_subcommand(&mut self) -> Option<(String, ArgMatches)> {
+        self.subcommand.take().map(|sc| (sc.name, sc.matches))
+    }
+
+    /// The `ArgMatches` for the current [subcommand].
+    ///
+    /// Subcommand values are put in a child [`ArgMatches`]
+    ///
+    /// Returns `None` if the subcommand wasn't present at runtime,
+    ///
+    /// # Panics
+    ///
+    /// If `id` is is not a valid subcommand.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use clap::{Command, Arg, ArgAction};
+    /// let app_m = Command::new("myprog")
+    ///     .arg(Arg::new("debug")
+    ///         .short('d')
+    ///         .action(ArgAction::SetTrue)
+    ///     )
+    ///     .subcommand(Command::new("test")
+    ///         .arg(Arg::new("opt")
+    ///             .long("option")
+    ///             .takes_value(true)))
+    ///     .get_matches_from(vec![
+    ///         "myprog", "-d", "test", "--option", "val"
+    ///     ]);
+    ///
+    /// // Both parent commands, and child subcommands can have arguments present at the same times
+    /// assert!(*app_m.get_one::<bool>("debug").expect("defaulted by clap"));
+    ///
+    /// // Get the subcommand's ArgMatches instance
+    /// if let Some(sub_m) = app_m.subcommand_matches("test") {
+    ///     // Use the struct like normal
+    ///     assert_eq!(sub_m.get_one::<String>("opt").map(|s| s.as_str()), Some("val"));
+    /// }
+    /// ```
+    ///
+    /// [subcommand]: crate::Command::subcommand
+    /// [`Command`]: crate::Command
+    pub fn subcommand_matches<T: Key>(&self, id: T) -> Option<&ArgMatches> {
+        self.get_subcommand(&id.into()).map(|sc| &sc.matches)
+    }
+
+    /// The name of the current [subcommand].
+    ///
+    /// Returns `None` if the subcommand wasn't present at runtime,
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use clap::{Command, Arg, };
+    ///  let app_m = Command::new("git")
+    ///      .subcommand(Command::new("clone"))
+    ///      .subcommand(Command::new("push"))
+    ///      .subcommand(Command::new("commit"))
+    ///      .get_matches();
+    ///
+    /// match app_m.subcommand_name() {
+    ///     Some("clone")  => {}, // clone was used
+    ///     Some("push")   => {}, // push was used
+    ///     Some("commit") => {}, // commit was used
+    ///     _              => {}, // Either no subcommand or one not tested for...
+    /// }
+    /// ```
+    /// [subcommand]: crate::Command::subcommand
+    /// [`Command`]: crate::Command
+    #[inline]
+    pub fn subcommand_name(&self) -> Option<&str> {
+        self.subcommand.as_ref().map(|sc| &*sc.name)
+    }
+
+    /// Check if a subcommand can be queried
+    ///
+    /// By default, `ArgMatches` functions assert on undefined `Id`s to help catch programmer
+    /// mistakes.  In some context, this doesn't work, so users can use this function to check
+    /// before they do a query on `ArgMatches`.
+    #[inline]
+    #[doc(hidden)]
+    pub fn is_valid_subcommand(&self, _id: impl Key) -> bool {
+        #[cfg(debug_assertions)]
+        {
+            let id = Id::from(_id);
+            self.disable_asserts || id == Id::empty_hash() || self.valid_subcommands.contains(&id)
+        }
+        #[cfg(not(debug_assertions))]
+        {
+            true
+        }
+    }
+}
+
+/// # Advanced
+impl ArgMatches {
+    /// Non-panicking version of [`ArgMatches::get_one`]
+    pub fn try_get_one<T: Any + Clone + Send + Sync + 'static>(
+        &self,
+        id: &str,
+    ) -> Result<Option<&T>, MatchesError> {
+        let id = Id::from(id);
+        let arg = self.try_get_arg_t::<T>(&id)?;
+        let value = match arg.and_then(|a| a.first()) {
+            Some(value) => value,
+            None => {
+                return Ok(None);
+            }
+        };
+        Ok(value
+            .downcast_ref::<T>()
+            .map(Some)
+            .expect(INTERNAL_ERROR_MSG)) // enforced by `try_get_arg_t`
+    }
+
+    /// Non-panicking version of [`ArgMatches::get_many`]
+    pub fn try_get_many<T: Any + Clone + Send + Sync + 'static>(
+        &self,
+        id: &str,
+    ) -> Result<Option<ValuesRef<T>>, MatchesError> {
+        let id = Id::from(id);
+        let arg = match self.try_get_arg_t::<T>(&id)? {
+            Some(arg) => arg,
+            None => return Ok(None),
+        };
+        let len = arg.num_vals();
+        let values = arg.vals_flatten();
+        let values = ValuesRef {
+            // enforced by `try_get_arg_t`
+            iter: values.map(|v| v.downcast_ref::<T>().expect(INTERNAL_ERROR_MSG)),
+            len,
+        };
+        Ok(Some(values))
+    }
+
+    /// Non-panicking version of [`ArgMatches::get_raw`]
+    pub fn try_get_raw(&self, id: &str) -> Result<Option<RawValues<'_>>, MatchesError> {
+        let id = Id::from(id);
+        let arg = match self.try_get_arg(&id)? {
+            Some(arg) => arg,
+            None => return Ok(None),
+        };
+        let len = arg.num_vals();
+        let values = arg.raw_vals_flatten();
+        let values = RawValues {
+            iter: values.map(OsString::as_os_str),
+            len,
+        };
+        Ok(Some(values))
+    }
+
+    /// Non-panicking version of [`ArgMatches::remove_one`]
+    pub fn try_remove_one<T: Any + Clone + Send + Sync + 'static>(
+        &mut self,
+        id: &str,
+    ) -> Result<Option<T>, MatchesError> {
+        let id = Id::from(id);
+        match self.try_remove_arg_t::<T>(&id)? {
+            Some(values) => Ok(values
+                .into_vals_flatten()
+                // enforced by `try_get_arg_t`
+                .map(|v| v.downcast_into::<T>().expect(INTERNAL_ERROR_MSG))
+                .next()),
+            None => Ok(None),
+        }
+    }
+
+    /// Non-panicking version of [`ArgMatches::remove_many`]
+    pub fn try_remove_many<T: Any + Clone + Send + Sync + 'static>(
+        &mut self,
+        id: &str,
+    ) -> Result<Option<Values2<T>>, MatchesError> {
+        let id = Id::from(id);
+        let arg = match self.try_remove_arg_t::<T>(&id)? {
+            Some(arg) => arg,
+            None => return Ok(None),
+        };
+        let len = arg.num_vals();
+        let values = arg.into_vals_flatten();
+        let values = Values2 {
+            // enforced by `try_get_arg_t`
+            iter: values.map(|v| v.downcast_into::<T>().expect(INTERNAL_ERROR_MSG)),
+            len,
+        };
+        Ok(Some(values))
+    }
+
+    /// Non-panicking version of [`ArgMatches::contains_id`]
+    pub fn try_contains_id(&self, id: &str) -> Result<bool, MatchesError> {
+        let id = Id::from(id);
+
+        self.verify_arg(&id)?;
+
+        let presence = self.args.contains_key(&id);
+        Ok(presence)
+    }
+}
+
+// Private methods
+impl ArgMatches {
+    #[inline]
+    fn try_get_arg(&self, arg: &Id) -> Result<Option<&MatchedArg>, MatchesError> {
+        self.verify_arg(arg)?;
+        Ok(self.args.get(arg))
+    }
+
+    #[inline]
+    fn try_get_arg_t<T: Any + Send + Sync + 'static>(
+        &self,
+        arg: &Id,
+    ) -> Result<Option<&MatchedArg>, MatchesError> {
+        let arg = match self.try_get_arg(arg)? {
+            Some(arg) => arg,
+            None => {
+                return Ok(None);
+            }
+        };
+        self.verify_arg_t::<T>(arg)?;
+        Ok(Some(arg))
+    }
+
+    #[inline]
+    fn try_remove_arg_t<T: Any + Send + Sync + 'static>(
+        &mut self,
+        arg: &Id,
+    ) -> Result<Option<MatchedArg>, MatchesError> {
+        self.verify_arg(arg)?;
+        let matched = match self.args.remove(arg) {
+            Some(matched) => matched,
+            None => {
+                return Ok(None);
+            }
+        };
+
+        let expected = AnyValueId::of::<T>();
+        let actual = matched.infer_type_id(expected);
+        if actual == expected {
+            Ok(Some(matched))
+        } else {
+            self.args.insert(arg.clone(), matched);
+            Err(MatchesError::Downcast { actual, expected })
+        }
+    }
+
+    fn verify_arg_t<T: Any + Send + Sync + 'static>(
+        &self,
+        arg: &MatchedArg,
+    ) -> Result<(), MatchesError> {
+        let expected = AnyValueId::of::<T>();
+        let actual = arg.infer_type_id(expected);
+        if expected == actual {
+            Ok(())
+        } else {
+            Err(MatchesError::Downcast { actual, expected })
+        }
+    }
+
+    #[inline]
+    fn verify_arg(&self, _arg: &Id) -> Result<(), MatchesError> {
+        #[cfg(debug_assertions)]
+        {
+            if self.disable_asserts || *_arg == Id::empty_hash() || self.valid_args.contains(_arg) {
+            } else if self.valid_subcommands.contains(_arg) {
+                debug!(
+                    "Subcommand `{:?}` used where an argument or group name was expected.",
+                    _arg
+                );
+                return Err(MatchesError::UnknownArgument {});
+            } else {
+                debug!(
+                    "`{:?}` is not an id of an argument or a group.\n\
+                     Make sure you're using the name of the argument itself \
+                     and not the name of short or long flags.",
+                    _arg
+                );
+                return Err(MatchesError::UnknownArgument {});
+            }
+        }
+        Ok(())
+    }
+
+    #[inline]
+    #[cfg_attr(debug_assertions, track_caller)]
+    fn get_arg(&self, arg: &Id) -> Option<&MatchedArg> {
+        #[cfg(debug_assertions)]
+        {
+            if self.disable_asserts || *arg == Id::empty_hash() || self.valid_args.contains(arg) {
+            } else if self.valid_subcommands.contains(arg) {
+                panic!(
+                    "Subcommand `{:?}` used where an argument or group name was expected.",
+                    arg
+                );
+            } else {
+                panic!(
+                    "`{:?}` is not an id of an argument or a group.\n\
+                     Make sure you're using the name of the argument itself \
+                     and not the name of short or long flags.",
+                    arg
+                );
+            }
+        }
+
+        self.args.get(arg)
+    }
+
+    #[inline]
+    #[cfg_attr(debug_assertions, track_caller)]
+    fn get_subcommand(&self, id: &Id) -> Option<&SubCommand> {
+        #[cfg(debug_assertions)]
+        {
+            if self.disable_asserts
+                || *id == Id::empty_hash()
+                || self.valid_subcommands.contains(id)
+            {
+            } else if self.valid_args.contains(id) {
+                panic!(
+                    "Argument or group `{:?}` used where a subcommand name was expected.",
+                    id
+                );
+            } else {
+                panic!("`{:?}` is not a name of a subcommand.", id);
+            }
+        }
+
+        if let Some(ref sc) = self.subcommand {
+            if sc.id == *id {
+                return Some(sc);
+            }
+        }
+
+        None
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub(crate) struct SubCommand {
+    pub(crate) id: Id,
+    pub(crate) name: String,
+    pub(crate) matches: ArgMatches,
+}
+
+/// Iterate over multiple values for an argument via [`ArgMatches::remove_many`].
+///
+/// # Examples
+///
+/// ```rust
+/// # use clap::{Command, Arg, ArgAction};
+/// let mut m = Command::new("myapp")
+///     .arg(Arg::new("output")
+///         .short('o')
+///         .action(ArgAction::Append)
+///         .takes_value(true))
+///     .get_matches_from(vec!["myapp", "-o", "val1", "-o", "val2"]);
+///
+/// let mut values = m.remove_many::<String>("output")
+///     .unwrap();
+///
+/// assert_eq!(values.next(), Some(String::from("val1")));
+/// assert_eq!(values.next(), Some(String::from("val2")));
+/// assert_eq!(values.next(), None);
+/// ```
+#[derive(Clone, Debug)]
+pub struct Values2<T> {
+    #[allow(clippy::type_complexity)]
+    iter: Map<Flatten<std::vec::IntoIter<Vec<AnyValue>>>, fn(AnyValue) -> T>,
+    len: usize,
+}
+
+impl<T> Iterator for Values2<T> {
+    type Item = T;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+impl<T> DoubleEndedIterator for Values2<T> {
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.iter.next_back()
+    }
+}
+
+impl<T> ExactSizeIterator for Values2<T> {}
+
+/// Creates an empty iterator.
+impl<T> Default for Values2<T> {
+    fn default() -> Self {
+        let empty: Vec<Vec<AnyValue>> = Default::default();
+        Values2 {
+            iter: empty.into_iter().flatten().map(|_| unreachable!()),
+            len: 0,
+        }
+    }
+}
+
+/// Iterate over multiple values for an argument via [`ArgMatches::get_many`].
+///
+/// # Examples
+///
+/// ```rust
+/// # use clap::{Command, Arg, ArgAction};
+/// let m = Command::new("myapp")
+///     .arg(Arg::new("output")
+///         .short('o')
+///         .action(ArgAction::Append)
+///         .takes_value(true))
+///     .get_matches_from(vec!["myapp", "-o", "val1", "-o", "val2"]);
+///
+/// let mut values = m.get_many::<String>("output")
+///     .unwrap()
+///     .map(|s| s.as_str());
+///
+/// assert_eq!(values.next(), Some("val1"));
+/// assert_eq!(values.next(), Some("val2"));
+/// assert_eq!(values.next(), None);
+/// ```
+#[derive(Clone, Debug)]
+pub struct ValuesRef<'a, T> {
+    #[allow(clippy::type_complexity)]
+    iter: Map<Flatten<Iter<'a, Vec<AnyValue>>>, fn(&AnyValue) -> &T>,
+    len: usize,
+}
+
+impl<'a, T: 'a> Iterator for ValuesRef<'a, T> {
+    type Item = &'a T;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+impl<'a, T: 'a> DoubleEndedIterator for ValuesRef<'a, T> {
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.iter.next_back()
+    }
+}
+
+impl<'a, T: 'a> ExactSizeIterator for ValuesRef<'a, T> {}
+
+/// Creates an empty iterator.
+impl<'a, T: 'a> Default for ValuesRef<'a, T> {
+    fn default() -> Self {
+        static EMPTY: [Vec<AnyValue>; 0] = [];
+        ValuesRef {
+            iter: EMPTY[..].iter().flatten().map(|_| unreachable!()),
+            len: 0,
+        }
+    }
+}
+
+/// Iterate over raw argument values via [`ArgMatches::get_raw`].
+///
+/// # Examples
+///
+#[cfg_attr(not(unix), doc = " ```ignore")]
+#[cfg_attr(unix, doc = " ```")]
+/// # use clap::{Command, arg, value_parser};
+/// use std::ffi::OsString;
+/// use std::os::unix::ffi::{OsStrExt,OsStringExt};
+///
+/// let m = Command::new("utf8")
+///     .arg(arg!(<arg> "some arg")
+///         .value_parser(value_parser!(OsString)))
+///     .get_matches_from(vec![OsString::from("myprog"),
+///                             // "Hi {0xe9}!"
+///                             OsString::from_vec(vec![b'H', b'i', b' ', 0xe9, b'!'])]);
+/// assert_eq!(
+///     &*m.get_raw("arg")
+///         .unwrap()
+///         .next().unwrap()
+///         .as_bytes(),
+///     [b'H', b'i', b' ', 0xe9, b'!']
+/// );
+/// ```
+#[derive(Clone, Debug)]
+pub struct RawValues<'a> {
+    #[allow(clippy::type_complexity)]
+    iter: Map<Flatten<Iter<'a, Vec<OsString>>>, fn(&OsString) -> &OsStr>,
+    len: usize,
+}
+
+impl<'a> Iterator for RawValues<'a> {
+    type Item = &'a OsStr;
+
+    fn next(&mut self) -> Option<&'a OsStr> {
+        self.iter.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+impl<'a> DoubleEndedIterator for RawValues<'a> {
+    fn next_back(&mut self) -> Option<&'a OsStr> {
+        self.iter.next_back()
+    }
+}
+
+impl<'a> ExactSizeIterator for RawValues<'a> {}
+
+/// Creates an empty iterator.
+impl Default for RawValues<'_> {
+    fn default() -> Self {
+        static EMPTY: [Vec<OsString>; 0] = [];
+        RawValues {
+            iter: EMPTY[..].iter().flatten().map(|_| unreachable!()),
+            len: 0,
+        }
+    }
+}
+
+// The following were taken and adapted from vec_map source
+// repo: https://github.com/contain-rs/vec-map
+// commit: be5e1fa3c26e351761b33010ddbdaf5f05dbcc33
+// license: MIT - Copyright (c) 2015 The Rust Project Developers
+
+/// Deprecated, replaced with [`ArgMatches::get_many()`]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_many()`")
+)]
+#[derive(Clone, Debug)]
+pub struct Values<'a> {
+    #[allow(clippy::type_complexity)]
+    iter: Map<Flatten<Iter<'a, Vec<AnyValue>>>, for<'r> fn(&'r AnyValue) -> &'r str>,
+    len: usize,
+}
+
+#[allow(deprecated)]
+impl<'a> Iterator for Values<'a> {
+    type Item = &'a str;
+
+    fn next(&mut self) -> Option<&'a str> {
+        self.iter.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+#[allow(deprecated)]
+impl<'a> DoubleEndedIterator for Values<'a> {
+    fn next_back(&mut self) -> Option<&'a str> {
+        self.iter.next_back()
+    }
+}
+
+#[allow(deprecated)]
+impl<'a> ExactSizeIterator for Values<'a> {}
+
+/// Creates an empty iterator.
+#[allow(deprecated)]
+impl<'a> Default for Values<'a> {
+    fn default() -> Self {
+        static EMPTY: [Vec<AnyValue>; 0] = [];
+        Values {
+            iter: EMPTY[..].iter().flatten().map(|_| unreachable!()),
+            len: 0,
+        }
+    }
+}
+
+#[derive(Clone)]
+#[allow(missing_debug_implementations)]
+pub struct GroupedValues<'a> {
+    #[allow(clippy::type_complexity)]
+    iter: Map<Iter<'a, Vec<AnyValue>>, fn(&Vec<AnyValue>) -> Vec<&str>>,
+    len: usize,
+}
+
+impl<'a> Iterator for GroupedValues<'a> {
+    type Item = Vec<&'a str>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+impl<'a> DoubleEndedIterator for GroupedValues<'a> {
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.iter.next_back()
+    }
+}
+
+impl<'a> ExactSizeIterator for GroupedValues<'a> {}
+
+/// Creates an empty iterator. Used for `unwrap_or_default()`.
+impl<'a> Default for GroupedValues<'a> {
+    fn default() -> Self {
+        #![allow(deprecated)]
+        static EMPTY: [Vec<AnyValue>; 0] = [];
+        GroupedValues {
+            iter: EMPTY[..].iter().map(|_| unreachable!()),
+            len: 0,
+        }
+    }
+}
+
+/// Deprecated, replaced with [`ArgMatches::get_many()`]
+#[cfg_attr(
+    feature = "deprecated",
+    deprecated(since = "3.2.0", note = "Replaced with `ArgMatches::get_many()`")
+)]
+#[derive(Clone, Debug)]
+pub struct OsValues<'a> {
+    #[allow(clippy::type_complexity)]
+    iter: Map<Flatten<Iter<'a, Vec<AnyValue>>>, fn(&AnyValue) -> &OsStr>,
+    len: usize,
+}
+
+#[allow(deprecated)]
+impl<'a> Iterator for OsValues<'a> {
+    type Item = &'a OsStr;
+
+    fn next(&mut self) -> Option<&'a OsStr> {
+        self.iter.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+#[allow(deprecated)]
+impl<'a> DoubleEndedIterator for OsValues<'a> {
+    fn next_back(&mut self) -> Option<&'a OsStr> {
+        self.iter.next_back()
+    }
+}
+
+#[allow(deprecated)]
+impl<'a> ExactSizeIterator for OsValues<'a> {}
+
+/// Creates an empty iterator.
+#[allow(deprecated)]
+impl Default for OsValues<'_> {
+    fn default() -> Self {
+        static EMPTY: [Vec<AnyValue>; 0] = [];
+        OsValues {
+            iter: EMPTY[..].iter().flatten().map(|_| unreachable!()),
+            len: 0,
+        }
+    }
+}
+
+/// Iterate over indices for where an argument appeared when parsing, via [`ArgMatches::indices_of`]
+///
+/// # Examples
+///
+/// ```rust
+/// # use clap::{Command, Arg};
+/// let m = Command::new("myapp")
+///     .arg(Arg::new("output")
+///         .short('o')
+///         .multiple_values(true)
+///         .takes_value(true))
+///     .get_matches_from(vec!["myapp", "-o", "val1", "val2"]);
+///
+/// let mut indices = m.indices_of("output").unwrap();
+///
+/// assert_eq!(indices.next(), Some(2));
+/// assert_eq!(indices.next(), Some(3));
+/// assert_eq!(indices.next(), None);
+/// ```
+/// [`ArgMatches::indices_of`]: ArgMatches::indices_of()
+#[derive(Clone, Debug)]
+pub struct Indices<'a> {
+    iter: Cloned<Iter<'a, usize>>,
+    len: usize,
+}
+
+impl<'a> Iterator for Indices<'a> {
+    type Item = usize;
+
+    fn next(&mut self) -> Option<usize> {
+        self.iter.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+impl<'a> DoubleEndedIterator for Indices<'a> {
+    fn next_back(&mut self) -> Option<usize> {
+        self.iter.next_back()
+    }
+}
+
+impl<'a> ExactSizeIterator for Indices<'a> {}
+
+/// Creates an empty iterator.
+impl<'a> Default for Indices<'a> {
+    fn default() -> Self {
+        static EMPTY: [usize; 0] = [];
+        // This is never called because the iterator is empty:
+        Indices {
+            iter: EMPTY[..].iter().cloned(),
+            len: 0,
+        }
+    }
+}
+
+#[cfg_attr(debug_assertions, track_caller)]
+#[inline]
+fn unwrap_string(value: &AnyValue) -> &str {
+    match value.downcast_ref::<String>() {
+        Some(value) => value,
+        None => {
+            panic!("Must use `_os` lookups with `Arg::allow_invalid_utf8`",)
+        }
+    }
+}
+
+#[cfg_attr(debug_assertions, track_caller)]
+#[inline]
+fn unwrap_string_arg<'v>(id: &Id, value: &'v AnyValue) -> &'v str {
+    match value.downcast_ref::<String>() {
+        Some(value) => value,
+        None => {
+            panic!(
+                "Must use `_os` lookups with `Arg::allow_invalid_utf8` at `{:?}`",
+                id
+            )
+        }
+    }
+}
+
+#[cfg_attr(debug_assertions, track_caller)]
+#[inline]
+fn unwrap_os_string(value: &AnyValue) -> &OsStr {
+    match value.downcast_ref::<OsString>() {
+        Some(value) => value,
+        None => {
+            panic!("Must use `Arg::allow_invalid_utf8` with `_os` lookups",)
+        }
+    }
+}
+
+#[cfg_attr(debug_assertions, track_caller)]
+#[inline]
+fn unwrap_os_string_arg<'v>(id: &Id, value: &'v AnyValue) -> &'v OsStr {
+    match value.downcast_ref::<OsString>() {
+        Some(value) => value,
+        None => {
+            panic!(
+                "Must use `Arg::allow_invalid_utf8` with `_os` lookups at `{:?}`",
+                id
+            )
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn check_auto_traits() {
+        static_assertions::assert_impl_all!(ArgMatches: Send, Sync, Unpin);
+    }
+
+    #[test]
+    fn test_default_values() {
+        #![allow(deprecated)]
+        let mut values: Values = Values::default();
+        assert_eq!(values.next(), None);
+    }
+
+    #[test]
+    fn test_default_osvalues() {
+        #![allow(deprecated)]
+        let mut values: OsValues = OsValues::default();
+        assert_eq!(values.next(), None);
+    }
+
+    #[test]
+    fn test_default_raw_values() {
+        let mut values: RawValues = Default::default();
+        assert_eq!(values.next(), None);
+    }
+
+    #[test]
+    fn test_default_indices() {
+        let mut indices: Indices = Indices::default();
+        assert_eq!(indices.next(), None);
+    }
+
+    #[test]
+    fn test_default_indices_with_shorter_lifetime() {
+        let matches = ArgMatches::default();
+        let mut indices = matches.indices_of("").unwrap_or_default();
+        assert_eq!(indices.next(), None);
+    }
+
+    #[test]
+    fn values_exact_size() {
+        let l = crate::Command::new("test")
+            .arg(
+                crate::Arg::new("POTATO")
+                    .takes_value(true)
+                    .multiple_values(true)
+                    .required(true),
+            )
+            .try_get_matches_from(["test", "one"])
+            .unwrap()
+            .get_many::<String>("POTATO")
+            .expect("present")
+            .count();
+        assert_eq!(l, 1);
+    }
+
+    #[test]
+    fn os_values_exact_size() {
+        let l = crate::Command::new("test")
+            .arg(
+                crate::Arg::new("POTATO")
+                    .takes_value(true)
+                    .multiple_values(true)
+                    .value_parser(crate::builder::ValueParser::os_string())
+                    .required(true),
+            )
+            .try_get_matches_from(["test", "one"])
+            .unwrap()
+            .get_many::<std::ffi::OsString>("POTATO")
+            .expect("present")
+            .count();
+        assert_eq!(l, 1);
+    }
+
+    #[test]
+    fn indices_exact_size() {
+        let l = crate::Command::new("test")
+            .arg(
+                crate::Arg::new("POTATO")
+                    .takes_value(true)
+                    .multiple_values(true)
+                    .required(true),
+            )
+            .try_get_matches_from(["test", "one"])
+            .unwrap()
+            .indices_of("POTATO")
+            .expect("present")
+            .len();
+        assert_eq!(l, 1);
+    }
+}
diff --git a/vendor/clap-3.2.20/src/parser/matches/matched_arg.rs b/vendor/clap-3.2.20/src/parser/matches/matched_arg.rs
new file mode 100644
index 000000000..fde6d37f3
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/matches/matched_arg.rs
@@ -0,0 +1,240 @@
+// Std
+use std::{
+    ffi::{OsStr, OsString},
+    iter::{Cloned, Flatten},
+    slice::Iter,
+};
+
+use crate::builder::ArgPredicate;
+use crate::parser::AnyValue;
+use crate::parser::AnyValueId;
+use crate::parser::ValueSource;
+use crate::util::eq_ignore_case;
+use crate::INTERNAL_ERROR_MSG;
+
+#[derive(Debug, Clone)]
+pub(crate) struct MatchedArg {
+    occurs: u64,
+    source: Option<ValueSource>,
+    indices: Vec<usize>,
+    type_id: Option<AnyValueId>,
+    vals: Vec<Vec<AnyValue>>,
+    raw_vals: Vec<Vec<OsString>>,
+    ignore_case: bool,
+}
+
+impl MatchedArg {
+    pub(crate) fn new_arg(arg: &crate::Arg) -> Self {
+        let ignore_case = arg.is_ignore_case_set();
+        Self {
+            occurs: 0,
+            source: None,
+            indices: Vec::new(),
+            type_id: Some(arg.get_value_parser().type_id()),
+            vals: Vec::new(),
+            raw_vals: Vec::new(),
+            ignore_case,
+        }
+    }
+
+    pub(crate) fn new_group() -> Self {
+        let ignore_case = false;
+        Self {
+            occurs: 0,
+            source: None,
+            indices: Vec::new(),
+            type_id: None,
+            vals: Vec::new(),
+            raw_vals: Vec::new(),
+            ignore_case,
+        }
+    }
+
+    pub(crate) fn new_external(cmd: &crate::Command) -> Self {
+        let ignore_case = false;
+        Self {
+            occurs: 0,
+            source: None,
+            indices: Vec::new(),
+            type_id: Some(
+                cmd.get_external_subcommand_value_parser()
+                    .expect(INTERNAL_ERROR_MSG)
+                    .type_id(),
+            ),
+            vals: Vec::new(),
+            raw_vals: Vec::new(),
+            ignore_case,
+        }
+    }
+
+    #[cfg_attr(feature = "deprecated", deprecated(since = "3.2.0"))]
+    pub(crate) fn inc_occurrences(&mut self) {
+        self.occurs += 1;
+    }
+
+    #[cfg_attr(feature = "deprecated", deprecated(since = "3.2.0"))]
+    pub(crate) fn set_occurrences(&mut self, occurs: u64) {
+        self.occurs = occurs
+    }
+
+    #[cfg_attr(feature = "deprecated", deprecated(since = "3.2.0"))]
+    pub(crate) fn get_occurrences(&self) -> u64 {
+        self.occurs
+    }
+
+    pub(crate) fn indices(&self) -> Cloned<Iter<'_, usize>> {
+        self.indices.iter().cloned()
+    }
+
+    pub(crate) fn get_index(&self, index: usize) -> Option<usize> {
+        self.indices.get(index).cloned()
+    }
+
+    pub(crate) fn push_index(&mut self, index: usize) {
+        self.indices.push(index)
+    }
+
+    #[cfg(feature = "unstable-grouped")]
+    pub(crate) fn vals(&self) -> Iter<Vec<AnyValue>> {
+        self.vals.iter()
+    }
+
+    pub(crate) fn vals_flatten(&self) -> Flatten<Iter<Vec<AnyValue>>> {
+        self.vals.iter().flatten()
+    }
+
+    pub(crate) fn into_vals_flatten(self) -> Flatten<std::vec::IntoIter<Vec<AnyValue>>> {
+        self.vals.into_iter().flatten()
+    }
+
+    pub(crate) fn raw_vals_flatten(&self) -> Flatten<Iter<Vec<OsString>>> {
+        self.raw_vals.iter().flatten()
+    }
+
+    pub(crate) fn first(&self) -> Option<&AnyValue> {
+        self.vals_flatten().next()
+    }
+
+    #[cfg(test)]
+    pub(crate) fn first_raw(&self) -> Option<&OsString> {
+        self.raw_vals_flatten().next()
+    }
+
+    pub(crate) fn new_val_group(&mut self) {
+        self.vals.push(vec![]);
+        self.raw_vals.push(vec![]);
+    }
+
+    pub(crate) fn append_val(&mut self, val: AnyValue, raw_val: OsString) {
+        // We assume there is always a group created before.
+        self.vals.last_mut().expect(INTERNAL_ERROR_MSG).push(val);
+        self.raw_vals
+            .last_mut()
+            .expect(INTERNAL_ERROR_MSG)
+            .push(raw_val);
+    }
+
+    pub(crate) fn num_vals(&self) -> usize {
+        self.vals.iter().map(|v| v.len()).sum()
+    }
+
+    // Will be used later
+    #[allow(dead_code)]
+    pub(crate) fn num_vals_last_group(&self) -> usize {
+        self.vals.last().map(|x| x.len()).unwrap_or(0)
+    }
+
+    pub(crate) fn all_val_groups_empty(&self) -> bool {
+        self.vals.iter().flatten().count() == 0
+    }
+
+    pub(crate) fn check_explicit(&self, predicate: ArgPredicate) -> bool {
+        if self.source == Some(ValueSource::DefaultValue) {
+            return false;
+        }
+
+        match predicate {
+            ArgPredicate::Equals(val) => self.raw_vals_flatten().any(|v| {
+                if self.ignore_case {
+                    // If `v` isn't utf8, it can't match `val`, so `OsStr::to_str` should be fine
+                    eq_ignore_case(&v.to_string_lossy(), &val.to_string_lossy())
+                } else {
+                    OsString::as_os_str(v) == OsStr::new(val)
+                }
+            }),
+            ArgPredicate::IsPresent => true,
+        }
+    }
+
+    pub(crate) fn source(&self) -> Option<ValueSource> {
+        self.source
+    }
+
+    pub(crate) fn set_source(&mut self, source: ValueSource) {
+        if let Some(existing) = self.source {
+            self.source = Some(existing.max(source));
+        } else {
+            self.source = Some(source)
+        }
+    }
+
+    pub(crate) fn type_id(&self) -> Option<AnyValueId> {
+        self.type_id
+    }
+
+    pub(crate) fn infer_type_id(&self, expected: AnyValueId) -> AnyValueId {
+        self.type_id()
+            .or_else(|| {
+                self.vals_flatten()
+                    .map(|v| v.type_id())
+                    .find(|actual| *actual != expected)
+            })
+            .unwrap_or(expected)
+    }
+}
+
+impl PartialEq for MatchedArg {
+    fn eq(&self, other: &MatchedArg) -> bool {
+        let MatchedArg {
+            occurs: self_occurs,
+            source: self_source,
+            indices: self_indices,
+            type_id: self_type_id,
+            vals: _,
+            raw_vals: self_raw_vals,
+            ignore_case: self_ignore_case,
+        } = self;
+        let MatchedArg {
+            occurs: other_occurs,
+            source: other_source,
+            indices: other_indices,
+            type_id: other_type_id,
+            vals: _,
+            raw_vals: other_raw_vals,
+            ignore_case: other_ignore_case,
+        } = other;
+        self_occurs == other_occurs
+            && self_source == other_source
+            && self_indices == other_indices
+            && self_type_id == other_type_id
+            && self_raw_vals == other_raw_vals
+            && self_ignore_case == other_ignore_case
+    }
+}
+
+impl Eq for MatchedArg {}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_grouped_vals_first() {
+        let mut m = MatchedArg::new_group();
+        m.new_val_group();
+        m.new_val_group();
+        m.append_val(AnyValue::new(String::from("bbb")), "bbb".into());
+        m.append_val(AnyValue::new(String::from("ccc")), "ccc".into());
+        assert_eq!(m.first_raw(), Some(&OsString::from("bbb")));
+    }
+}
diff --git a/vendor/clap-3.2.20/src/parser/matches/mod.rs b/vendor/clap-3.2.20/src/parser/matches/mod.rs
new file mode 100644
index 000000000..7b88eeca7
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/matches/mod.rs
@@ -0,0 +1,17 @@
+mod any_value;
+mod arg_matches;
+mod matched_arg;
+mod value_source;
+
+pub use any_value::AnyValueId;
+pub use arg_matches::RawValues;
+pub use arg_matches::ValuesRef;
+pub use arg_matches::{ArgMatches, Indices};
+pub use value_source::ValueSource;
+
+pub(crate) use any_value::AnyValue;
+pub(crate) use arg_matches::SubCommand;
+pub(crate) use matched_arg::MatchedArg;
+
+#[allow(deprecated)]
+pub use arg_matches::{OsValues, Values};
diff --git a/vendor/clap-3.2.20/src/parser/matches/value_source.rs b/vendor/clap-3.2.20/src/parser/matches/value_source.rs
new file mode 100644
index 000000000..fb762d2af
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/matches/value_source.rs
@@ -0,0 +1,11 @@
+/// Origin of the argument's value
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+#[non_exhaustive]
+pub enum ValueSource {
+    /// Value came [`Arg::default_value`][crate::Arg::default_value]
+    DefaultValue,
+    /// Value came [`Arg::env`][crate::Arg::env]
+    EnvVariable,
+    /// Value was passed in on the command-line
+    CommandLine,
+}
diff --git a/vendor/clap-3.2.20/src/parser/mod.rs b/vendor/clap-3.2.20/src/parser/mod.rs
new file mode 100644
index 000000000..da81648e1
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/mod.rs
@@ -0,0 +1,27 @@
+//! [`Command`][crate::Command] line argument parser
+
+mod arg_matcher;
+mod error;
+mod matches;
+#[allow(clippy::module_inception)]
+mod parser;
+mod validator;
+
+pub(crate) mod features;
+
+pub(crate) use self::arg_matcher::ArgMatcher;
+pub(crate) use self::matches::AnyValue;
+pub(crate) use self::matches::AnyValueId;
+pub(crate) use self::matches::{MatchedArg, SubCommand};
+pub(crate) use self::parser::Identifier;
+pub(crate) use self::parser::PendingArg;
+pub(crate) use self::parser::{ParseState, Parser};
+pub(crate) use self::validator::Validator;
+
+pub use self::matches::RawValues;
+pub use self::matches::ValuesRef;
+pub use self::matches::{ArgMatches, Indices, ValueSource};
+pub use error::MatchesError;
+
+#[allow(deprecated)]
+pub use self::matches::{OsValues, Values};
diff --git a/vendor/clap-3.2.20/src/parser/parser.rs b/vendor/clap-3.2.20/src/parser/parser.rs
new file mode 100644
index 000000000..ad2bc6e9c
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/parser.rs
@@ -0,0 +1,1729 @@
+// Std
+use std::{
+    cell::Cell,
+    ffi::{OsStr, OsString},
+};
+
+// Third Party
+use clap_lex::RawOsStr;
+
+// Internal
+use crate::builder::AppSettings as AS;
+use crate::builder::{Arg, Command};
+use crate::error::Error as ClapError;
+use crate::error::Result as ClapResult;
+use crate::mkeymap::KeyType;
+use crate::output::fmt::Stream;
+use crate::output::{fmt::Colorizer, Usage};
+use crate::parser::features::suggestions;
+use crate::parser::{ArgMatcher, SubCommand};
+use crate::parser::{Validator, ValueSource};
+use crate::util::Id;
+use crate::ArgAction;
+use crate::{INTERNAL_ERROR_MSG, INVALID_UTF8};
+
+pub(crate) struct Parser<'help, 'cmd> {
+    cmd: &'cmd mut Command<'help>,
+    cur_idx: Cell<usize>,
+    /// Index of the previous flag subcommand in a group of flags.
+    flag_subcmd_at: Option<usize>,
+    /// Counter indicating the number of items to skip
+    /// when revisiting the group of flags which includes the flag subcommand.
+    flag_subcmd_skip: usize,
+}
+
+// Initializing Methods
+impl<'help, 'cmd> Parser<'help, 'cmd> {
+    pub(crate) fn new(cmd: &'cmd mut Command<'help>) -> Self {
+        Parser {
+            cmd,
+            cur_idx: Cell::new(0),
+            flag_subcmd_at: None,
+            flag_subcmd_skip: 0,
+        }
+    }
+}
+
+// Parsing Methods
+impl<'help, 'cmd> Parser<'help, 'cmd> {
+    // The actual parsing function
+    #[allow(clippy::cognitive_complexity)]
+    pub(crate) fn get_matches_with(
+        &mut self,
+        matcher: &mut ArgMatcher,
+        raw_args: &mut clap_lex::RawArgs,
+        mut args_cursor: clap_lex::ArgCursor,
+    ) -> ClapResult<()> {
+        debug!("Parser::get_matches_with");
+        // Verify all positional assertions pass
+
+        let mut subcmd_name: Option<String> = None;
+        let mut keep_state = false;
+        let mut parse_state = ParseState::ValuesDone;
+        let mut pos_counter = 1;
+
+        // Already met any valid arg(then we shouldn't expect subcommands after it).
+        let mut valid_arg_found = false;
+        // If the user already passed '--'. Meaning only positional args follow.
+        let mut trailing_values = false;
+
+        // Count of positional args
+        let positional_count = self
+            .cmd
+            .get_keymap()
+            .keys()
+            .filter(|x| x.is_position())
+            .count();
+        // If any arg sets .last(true)
+        let contains_last = self.cmd.get_arguments().any(|x| x.is_last_set());
+
+        while let Some(arg_os) = raw_args.next(&mut args_cursor) {
+            // Recover the replaced items if any.
+            if let Some(replaced_items) = arg_os
+                .to_value()
+                .ok()
+                .and_then(|a| self.cmd.get_replacement(a))
+            {
+                debug!(
+                    "Parser::get_matches_with: found replacer: {:?}, target: {:?}",
+                    arg_os, replaced_items
+                );
+                raw_args.insert(&args_cursor, replaced_items);
+                continue;
+            }
+
+            debug!(
+                "Parser::get_matches_with: Begin parsing '{:?}' ({:?})",
+                arg_os.to_value_os(),
+                arg_os.to_value_os().as_raw_bytes()
+            );
+
+            // Has the user already passed '--'? Meaning only positional args follow
+            if !trailing_values {
+                if self.cmd.is_subcommand_precedence_over_arg_set()
+                    || !matches!(parse_state, ParseState::Opt(_) | ParseState::Pos(_))
+                {
+                    // Does the arg match a subcommand name, or any of its aliases (if defined)
+                    let sc_name = self.possible_subcommand(arg_os.to_value(), valid_arg_found);
+                    debug!("Parser::get_matches_with: sc={:?}", sc_name);
+                    if let Some(sc_name) = sc_name {
+                        #[allow(deprecated)]
+                        if sc_name == "help"
+                            && !self.is_set(AS::NoAutoHelp)
+                            && !self.cmd.is_disable_help_subcommand_set()
+                        {
+                            self.parse_help_subcommand(raw_args.remaining(&mut args_cursor))?;
+                            unreachable!("`parse_help_subcommand` always errors");
+                        } else {
+                            subcmd_name = Some(sc_name.to_owned());
+                        }
+                        break;
+                    }
+                }
+
+                if arg_os.is_escape() {
+                    if matches!(&parse_state, ParseState::Opt(opt) | ParseState::Pos(opt) if
+                        self.cmd[opt].is_allow_hyphen_values_set())
+                    {
+                        // ParseResult::MaybeHyphenValue, do nothing
+                    } else {
+                        debug!("Parser::get_matches_with: setting TrailingVals=true");
+                        trailing_values = true;
+                        continue;
+                    }
+                } else if let Some((long_arg, long_value)) = arg_os.to_long() {
+                    let parse_result = self.parse_long_arg(
+                        matcher,
+                        long_arg,
+                        long_value,
+                        &parse_state,
+                        &mut valid_arg_found,
+                        trailing_values,
+                    )?;
+                    debug!(
+                        "Parser::get_matches_with: After parse_long_arg {:?}",
+                        parse_result
+                    );
+                    match parse_result {
+                        ParseResult::NoArg => {
+                            unreachable!("`to_long` always has the flag specified")
+                        }
+                        ParseResult::ValuesDone => {
+                            parse_state = ParseState::ValuesDone;
+                            continue;
+                        }
+                        ParseResult::Opt(id) => {
+                            parse_state = ParseState::Opt(id);
+                            continue;
+                        }
+                        ParseResult::FlagSubCommand(name) => {
+                            debug!(
+                                "Parser::get_matches_with: FlagSubCommand found in long arg {:?}",
+                                &name
+                            );
+                            subcmd_name = Some(name);
+                            break;
+                        }
+                        ParseResult::EqualsNotProvided { arg } => {
+                            let _ = self.resolve_pending(matcher);
+                            return Err(ClapError::no_equals(
+                                self.cmd,
+                                arg,
+                                Usage::new(self.cmd).create_usage_with_title(&[]),
+                            ));
+                        }
+                        ParseResult::NoMatchingArg { arg } => {
+                            let _ = self.resolve_pending(matcher);
+                            let remaining_args: Vec<_> = raw_args
+                                .remaining(&mut args_cursor)
+                                .map(|x| x.to_str().expect(INVALID_UTF8))
+                                .collect();
+                            return Err(self.did_you_mean_error(&arg, matcher, &remaining_args));
+                        }
+                        ParseResult::UnneededAttachedValue { rest, used, arg } => {
+                            let _ = self.resolve_pending(matcher);
+                            return Err(ClapError::too_many_values(
+                                self.cmd,
+                                rest,
+                                arg,
+                                Usage::new(self.cmd).create_usage_no_title(&used),
+                            ));
+                        }
+                        ParseResult::MaybeHyphenValue => {
+                            // Maybe a hyphen value, do nothing.
+                        }
+                        ParseResult::AttachedValueNotConsumed => {
+                            unreachable!()
+                        }
+                    }
+                } else if let Some(short_arg) = arg_os.to_short() {
+                    // Arg looks like a short flag, and not a possible number
+
+                    // Try to parse short args like normal, if allow_hyphen_values or
+                    // AllowNegativeNumbers is set, parse_short_arg will *not* throw
+                    // an error, and instead return Ok(None)
+                    let parse_result = self.parse_short_arg(
+                        matcher,
+                        short_arg,
+                        &parse_state,
+                        pos_counter,
+                        &mut valid_arg_found,
+                        trailing_values,
+                    )?;
+                    // If it's None, we then check if one of those two AppSettings was set
+                    debug!(
+                        "Parser::get_matches_with: After parse_short_arg {:?}",
+                        parse_result
+                    );
+                    match parse_result {
+                        ParseResult::NoArg => {
+                            // Is a single dash `-`, try positional.
+                        }
+                        ParseResult::ValuesDone => {
+                            parse_state = ParseState::ValuesDone;
+                            continue;
+                        }
+                        ParseResult::Opt(id) => {
+                            parse_state = ParseState::Opt(id);
+                            continue;
+                        }
+                        ParseResult::FlagSubCommand(name) => {
+                            // If there are more short flags to be processed, we should keep the state, and later
+                            // revisit the current group of short flags skipping the subcommand.
+                            keep_state = self
+                                .flag_subcmd_at
+                                .map(|at| {
+                                    raw_args
+                                        .seek(&mut args_cursor, clap_lex::SeekFrom::Current(-1));
+                                    // Since we are now saving the current state, the number of flags to skip during state recovery should
+                                    // be the current index (`cur_idx`) minus ONE UNIT TO THE LEFT of the starting position.
+                                    self.flag_subcmd_skip = self.cur_idx.get() - at + 1;
+                                })
+                                .is_some();
+
+                            debug!(
+                                "Parser::get_matches_with:FlagSubCommandShort: subcmd_name={}, keep_state={}, flag_subcmd_skip={}",
+                                name,
+                                keep_state,
+                                self.flag_subcmd_skip
+                            );
+
+                            subcmd_name = Some(name);
+                            break;
+                        }
+                        ParseResult::EqualsNotProvided { arg } => {
+                            let _ = self.resolve_pending(matcher);
+                            return Err(ClapError::no_equals(
+                                self.cmd,
+                                arg,
+                                Usage::new(self.cmd).create_usage_with_title(&[]),
+                            ));
+                        }
+                        ParseResult::NoMatchingArg { arg } => {
+                            let _ = self.resolve_pending(matcher);
+                            return Err(ClapError::unknown_argument(
+                                self.cmd,
+                                arg,
+                                None,
+                                Usage::new(self.cmd).create_usage_with_title(&[]),
+                            ));
+                        }
+                        ParseResult::MaybeHyphenValue => {
+                            // Maybe a hyphen value, do nothing.
+                        }
+                        ParseResult::UnneededAttachedValue { .. }
+                        | ParseResult::AttachedValueNotConsumed => unreachable!(),
+                    }
+                }
+
+                if let ParseState::Opt(id) = &parse_state {
+                    // Assume this is a value of a previous arg.
+
+                    // get the option so we can check the settings
+                    let arg_values = matcher.pending_values_mut(id, None);
+                    let arg = &self.cmd[id];
+                    let parse_result = self.split_arg_values(
+                        arg,
+                        arg_os.to_value_os(),
+                        trailing_values,
+                        arg_values,
+                    );
+                    let parse_result = parse_result.unwrap_or_else(|| {
+                        if matcher.needs_more_vals(arg) {
+                            ParseResult::Opt(arg.id.clone())
+                        } else {
+                            ParseResult::ValuesDone
+                        }
+                    });
+                    parse_state = match parse_result {
+                        ParseResult::Opt(id) => ParseState::Opt(id),
+                        ParseResult::ValuesDone => ParseState::ValuesDone,
+                        _ => unreachable!(),
+                    };
+                    // get the next value from the iterator
+                    continue;
+                }
+            }
+
+            // Correct pos_counter.
+            pos_counter = {
+                let is_second_to_last = pos_counter + 1 == positional_count;
+
+                // The last positional argument, or second to last positional
+                // argument may be set to .multiple_values(true) or `.multiple_occurrences(true)`
+                let low_index_mults = is_second_to_last
+                    && self
+                        .cmd
+                        .get_positionals()
+                        .any(|a| a.is_multiple() && (positional_count != a.index.unwrap_or(0)))
+                    && self
+                        .cmd
+                        .get_positionals()
+                        .last()
+                        .map_or(false, |p_name| !p_name.is_last_set());
+
+                let missing_pos = self.cmd.is_allow_missing_positional_set()
+                    && is_second_to_last
+                    && !trailing_values;
+
+                debug!(
+                    "Parser::get_matches_with: Positional counter...{}",
+                    pos_counter
+                );
+                debug!(
+                    "Parser::get_matches_with: Low index multiples...{:?}",
+                    low_index_mults
+                );
+
+                if low_index_mults || missing_pos {
+                    let skip_current = if let Some(n) = raw_args.peek(&args_cursor) {
+                        if let Some(arg) = self
+                            .cmd
+                            .get_positionals()
+                            .find(|a| a.index == Some(pos_counter))
+                        {
+                            // If next value looks like a new_arg or it's a
+                            // subcommand, skip positional argument under current
+                            // pos_counter(which means current value cannot be a
+                            // positional argument with a value next to it), assume
+                            // current value matches the next arg.
+                            self.is_new_arg(&n, arg)
+                                || self
+                                    .possible_subcommand(n.to_value(), valid_arg_found)
+                                    .is_some()
+                        } else {
+                            true
+                        }
+                    } else {
+                        true
+                    };
+
+                    if skip_current {
+                        debug!("Parser::get_matches_with: Bumping the positional counter...");
+                        pos_counter + 1
+                    } else {
+                        pos_counter
+                    }
+                } else if trailing_values
+                    && (self.cmd.is_allow_missing_positional_set() || contains_last)
+                {
+                    // Came to -- and one positional has .last(true) set, so we go immediately
+                    // to the last (highest index) positional
+                    debug!("Parser::get_matches_with: .last(true) and --, setting last pos");
+                    positional_count
+                } else {
+                    pos_counter
+                }
+            };
+
+            if let Some(arg) = self.cmd.get_keymap().get(&pos_counter) {
+                if arg.is_last_set() && !trailing_values {
+                    let _ = self.resolve_pending(matcher);
+                    return Err(ClapError::unknown_argument(
+                        self.cmd,
+                        arg_os.display().to_string(),
+                        None,
+                        Usage::new(self.cmd).create_usage_with_title(&[]),
+                    ));
+                }
+
+                if self.cmd.is_trailing_var_arg_set() && pos_counter == positional_count {
+                    trailing_values = true;
+                }
+
+                if matcher.pending_arg_id() != Some(&arg.id) || !arg.is_multiple_values_set() {
+                    self.resolve_pending(matcher)?;
+                }
+                let arg_values = matcher.pending_values_mut(&arg.id, Some(Identifier::Index));
+                let _parse_result =
+                    self.split_arg_values(arg, arg_os.to_value_os(), trailing_values, arg_values);
+                if let Some(_parse_result) = _parse_result {
+                    if _parse_result != ParseResult::ValuesDone {
+                        debug!(
+                            "Parser::get_matches_with: Ignoring state {:?}; positionals do their own thing",
+                            _parse_result
+                        );
+                    }
+                }
+
+                // Only increment the positional counter if it doesn't allow multiples
+                if !arg.is_multiple() {
+                    pos_counter += 1;
+                    parse_state = ParseState::ValuesDone;
+                } else {
+                    parse_state = ParseState::Pos(arg.id.clone());
+                }
+                valid_arg_found = true;
+            } else if let Some(external_parser) =
+                self.cmd.get_external_subcommand_value_parser().cloned()
+            {
+                // Get external subcommand name
+                let sc_name = match arg_os.to_value() {
+                    Ok(s) => s.to_string(),
+                    Err(_) => {
+                        let _ = self.resolve_pending(matcher);
+                        return Err(ClapError::invalid_utf8(
+                            self.cmd,
+                            Usage::new(self.cmd).create_usage_with_title(&[]),
+                        ));
+                    }
+                };
+
+                // Collect the external subcommand args
+                let mut sc_m = ArgMatcher::new(self.cmd);
+                if cfg!(feature = "unstable-v4") || !raw_args.is_end(&args_cursor) {
+                    sc_m.start_occurrence_of_external(self.cmd);
+                }
+
+                for raw_val in raw_args.remaining(&mut args_cursor) {
+                    let val = external_parser.parse_ref(self.cmd, None, raw_val)?;
+                    let external_id = &Id::empty_hash();
+                    sc_m.add_val_to(external_id, val, raw_val.to_os_string());
+                }
+
+                matcher.subcommand(SubCommand {
+                    id: Id::from(&*sc_name),
+                    name: sc_name,
+                    matches: sc_m.into_inner(),
+                });
+
+                self.resolve_pending(matcher)?;
+                #[cfg(feature = "env")]
+                self.add_env(matcher)?;
+                self.add_defaults(matcher)?;
+                return Validator::new(self.cmd).validate(parse_state, matcher);
+            } else {
+                // Start error processing
+                let _ = self.resolve_pending(matcher);
+                return Err(self.match_arg_error(&arg_os, valid_arg_found, trailing_values));
+            }
+        }
+
+        if let Some(ref pos_sc_name) = subcmd_name {
+            let sc_name = self
+                .cmd
+                .find_subcommand(pos_sc_name)
+                .expect(INTERNAL_ERROR_MSG)
+                .get_name()
+                .to_owned();
+            self.parse_subcommand(&sc_name, matcher, raw_args, args_cursor, keep_state)?;
+        }
+
+        self.resolve_pending(matcher)?;
+        #[cfg(feature = "env")]
+        self.add_env(matcher)?;
+        self.add_defaults(matcher)?;
+        Validator::new(self.cmd).validate(parse_state, matcher)
+    }
+
+    fn match_arg_error(
+        &self,
+        arg_os: &clap_lex::ParsedArg<'_>,
+        valid_arg_found: bool,
+        trailing_values: bool,
+    ) -> ClapError {
+        // If argument follows a `--`
+        if trailing_values {
+            // If the arg matches a subcommand name, or any of its aliases (if defined)
+            if self
+                .possible_subcommand(arg_os.to_value(), valid_arg_found)
+                .is_some()
+            {
+                return ClapError::unnecessary_double_dash(
+                    self.cmd,
+                    arg_os.display().to_string(),
+                    Usage::new(self.cmd).create_usage_with_title(&[]),
+                );
+            }
+        }
+        let candidates = suggestions::did_you_mean(
+            &arg_os.display().to_string(),
+            self.cmd.all_subcommand_names(),
+        );
+        // If the argument looks like a subcommand.
+        if !candidates.is_empty() {
+            let candidates: Vec<_> = candidates
+                .iter()
+                .map(|candidate| format!("'{}'", candidate))
+                .collect();
+            return ClapError::invalid_subcommand(
+                self.cmd,
+                arg_os.display().to_string(),
+                candidates.join(" or "),
+                self.cmd
+                    .get_bin_name()
+                    .unwrap_or_else(|| self.cmd.get_name())
+                    .to_owned(),
+                Usage::new(self.cmd).create_usage_with_title(&[]),
+            );
+        }
+        // If the argument must be a subcommand.
+        if !self.cmd.has_args() || self.cmd.is_infer_subcommands_set() && self.cmd.has_subcommands()
+        {
+            return ClapError::unrecognized_subcommand(
+                self.cmd,
+                arg_os.display().to_string(),
+                Usage::new(self.cmd).create_usage_with_title(&[]),
+            );
+        }
+        ClapError::unknown_argument(
+            self.cmd,
+            arg_os.display().to_string(),
+            None,
+            Usage::new(self.cmd).create_usage_with_title(&[]),
+        )
+    }
+
+    // Checks if the arg matches a subcommand name, or any of its aliases (if defined)
+    fn possible_subcommand(
+        &self,
+        arg: Result<&str, &RawOsStr>,
+        valid_arg_found: bool,
+    ) -> Option<&str> {
+        debug!("Parser::possible_subcommand: arg={:?}", arg);
+        let arg = arg.ok()?;
+
+        if !(self.cmd.is_args_conflicts_with_subcommands_set() && valid_arg_found) {
+            if self.cmd.is_infer_subcommands_set() {
+                // For subcommand `test`, we accepts it's prefix: `t`, `te`,
+                // `tes` and `test`.
+                let v = self
+                    .cmd
+                    .all_subcommand_names()
+                    .filter(|s| s.starts_with(arg))
+                    .collect::<Vec<_>>();
+
+                if v.len() == 1 {
+                    return Some(v[0]);
+                }
+
+                // If there is any ambiguity, fallback to non-infer subcommand
+                // search.
+            }
+            if let Some(sc) = self.cmd.find_subcommand(arg) {
+                return Some(sc.get_name());
+            }
+        }
+        None
+    }
+
+    // Checks if the arg matches a long flag subcommand name, or any of its aliases (if defined)
+    fn possible_long_flag_subcommand(&self, arg: &str) -> Option<&str> {
+        debug!("Parser::possible_long_flag_subcommand: arg={:?}", arg);
+        if self.cmd.is_infer_subcommands_set() {
+            let options = self
+                .cmd
+                .get_subcommands()
+                .fold(Vec::new(), |mut options, sc| {
+                    if let Some(long) = sc.get_long_flag() {
+                        if long.starts_with(arg) {
+                            options.push(long);
+                        }
+                        options.extend(sc.get_all_aliases().filter(|alias| alias.starts_with(arg)))
+                    }
+                    options
+                });
+            if options.len() == 1 {
+                return Some(options[0]);
+            }
+
+            for sc in options {
+                if sc == arg {
+                    return Some(sc);
+                }
+            }
+        } else if let Some(sc_name) = self.cmd.find_long_subcmd(arg) {
+            return Some(sc_name);
+        }
+        None
+    }
+
+    fn parse_help_subcommand(
+        &self,
+        cmds: impl Iterator<Item = &'cmd OsStr>,
+    ) -> ClapResult<std::convert::Infallible> {
+        debug!("Parser::parse_help_subcommand");
+
+        let mut cmd = self.cmd.clone();
+        let sc = {
+            let mut sc = &mut cmd;
+
+            for cmd in cmds {
+                sc = if let Some(sc_name) =
+                    sc.find_subcommand(cmd).map(|sc| sc.get_name().to_owned())
+                {
+                    sc._build_subcommand(&sc_name).unwrap()
+                } else {
+                    return Err(ClapError::unrecognized_subcommand(
+                        sc,
+                        cmd.to_string_lossy().into_owned(),
+                        Usage::new(sc).create_usage_with_title(&[]),
+                    ));
+                };
+            }
+
+            sc
+        };
+        let parser = Parser::new(sc);
+
+        Err(parser.help_err(true, Stream::Stdout))
+    }
+
+    fn is_new_arg(&self, next: &clap_lex::ParsedArg<'_>, current_positional: &Arg) -> bool {
+        #![allow(clippy::needless_bool)] // Prefer consistent if/else-if ladder
+
+        debug!(
+            "Parser::is_new_arg: {:?}:{:?}",
+            next.to_value_os(),
+            current_positional.name
+        );
+
+        if self.cmd.is_allow_hyphen_values_set()
+            || self.cmd[&current_positional.id].is_allow_hyphen_values_set()
+            || (self.cmd.is_allow_negative_numbers_set() && next.is_number())
+        {
+            // If allow hyphen, this isn't a new arg.
+            debug!("Parser::is_new_arg: Allow hyphen");
+            false
+        } else if next.is_long() {
+            // If this is a long flag, this is a new arg.
+            debug!("Parser::is_new_arg: --<something> found");
+            true
+        } else if next.is_short() {
+            // If this is a short flag, this is a new arg. But a singe '-' by
+            // itself is a value and typically means "stdin" on unix systems.
+            debug!("Parser::is_new_arg: -<something> found");
+            true
+        } else {
+            // Nothing special, this is a value.
+            debug!("Parser::is_new_arg: value");
+            false
+        }
+    }
+
+    fn parse_subcommand(
+        &mut self,
+        sc_name: &str,
+        matcher: &mut ArgMatcher,
+        raw_args: &mut clap_lex::RawArgs,
+        args_cursor: clap_lex::ArgCursor,
+        keep_state: bool,
+    ) -> ClapResult<()> {
+        debug!("Parser::parse_subcommand");
+
+        let partial_parsing_enabled = self.cmd.is_ignore_errors_set();
+
+        if let Some(sc) = self.cmd._build_subcommand(sc_name) {
+            let mut sc_matcher = ArgMatcher::new(sc);
+
+            debug!(
+                "Parser::parse_subcommand: About to parse sc={}",
+                sc.get_name()
+            );
+
+            {
+                let mut p = Parser::new(sc);
+                // HACK: maintain indexes between parsers
+                // FlagSubCommand short arg needs to revisit the current short args, but skip the subcommand itself
+                if keep_state {
+                    p.cur_idx.set(self.cur_idx.get());
+                    p.flag_subcmd_at = self.flag_subcmd_at;
+                    p.flag_subcmd_skip = self.flag_subcmd_skip;
+                }
+                if let Err(error) = p.get_matches_with(&mut sc_matcher, raw_args, args_cursor) {
+                    if partial_parsing_enabled {
+                        debug!(
+                            "Parser::parse_subcommand: ignored error in subcommand {}: {:?}",
+                            sc_name, error
+                        );
+                    } else {
+                        return Err(error);
+                    }
+                }
+            }
+            matcher.subcommand(SubCommand {
+                id: sc.get_id(),
+                name: sc.get_name().to_owned(),
+                matches: sc_matcher.into_inner(),
+            });
+        }
+        Ok(())
+    }
+
+    fn parse_long_arg(
+        &mut self,
+        matcher: &mut ArgMatcher,
+        long_arg: Result<&str, &RawOsStr>,
+        long_value: Option<&RawOsStr>,
+        parse_state: &ParseState,
+        valid_arg_found: &mut bool,
+        trailing_values: bool,
+    ) -> ClapResult<ParseResult> {
+        // maybe here lifetime should be 'a
+        debug!("Parser::parse_long_arg");
+
+        if matches!(parse_state, ParseState::Opt(opt) | ParseState::Pos(opt) if
+            self.cmd[opt].is_allow_hyphen_values_set())
+        {
+            return Ok(ParseResult::MaybeHyphenValue);
+        }
+
+        debug!("Parser::parse_long_arg: Does it contain '='...");
+        let long_arg = match long_arg {
+            Ok(long_arg) => long_arg,
+            Err(long_arg) => {
+                return Ok(ParseResult::NoMatchingArg {
+                    arg: long_arg.to_str_lossy().into_owned(),
+                });
+            }
+        };
+        if long_arg.is_empty() {
+            debug_assert!(
+                long_value.is_some(),
+                "`--` should be filtered out before this point"
+            );
+        }
+
+        let arg = if let Some(arg) = self.cmd.get_keymap().get(long_arg) {
+            debug!(
+                "Parser::parse_long_arg: Found valid arg or flag '{}'",
+                arg.to_string()
+            );
+            Some((long_arg, arg))
+        } else if self.cmd.is_infer_long_args_set() {
+            self.cmd.get_arguments().find_map(|a| {
+                if let Some(long) = a.long {
+                    if long.starts_with(long_arg) {
+                        return Some((long, a));
+                    }
+                }
+                a.aliases
+                    .iter()
+                    .find_map(|(alias, _)| alias.starts_with(long_arg).then(|| (*alias, a)))
+            })
+        } else {
+            None
+        };
+
+        if let Some((_long_arg, arg)) = arg {
+            let ident = Identifier::Long;
+            *valid_arg_found = true;
+            if arg.is_takes_value_set() {
+                debug!(
+                    "Parser::parse_long_arg({:?}): Found an arg with value '{:?}'",
+                    long_arg, &long_value
+                );
+                let has_eq = long_value.is_some();
+                self.parse_opt_value(ident, long_value, arg, matcher, trailing_values, has_eq)
+            } else if let Some(rest) = long_value {
+                let required = self.cmd.required_graph();
+                debug!(
+                    "Parser::parse_long_arg({:?}): Got invalid literal `{:?}`",
+                    long_arg, rest
+                );
+                let used: Vec<Id> = matcher
+                    .arg_ids()
+                    .filter(|arg_id| {
+                        matcher.check_explicit(arg_id, crate::builder::ArgPredicate::IsPresent)
+                    })
+                    .filter(|&n| {
+                        self.cmd
+                            .find(n)
+                            .map_or(true, |a| !(a.is_hide_set() || required.contains(&a.id)))
+                    })
+                    .cloned()
+                    .collect();
+
+                Ok(ParseResult::UnneededAttachedValue {
+                    rest: rest.to_str_lossy().into_owned(),
+                    used,
+                    arg: arg.to_string(),
+                })
+            } else {
+                debug!("Parser::parse_long_arg({:?}): Presence validated", long_arg);
+                self.react(Some(ident), ValueSource::CommandLine, arg, vec![], matcher)
+            }
+        } else if let Some(sc_name) = self.possible_long_flag_subcommand(long_arg) {
+            Ok(ParseResult::FlagSubCommand(sc_name.to_string()))
+        } else if self.cmd.is_allow_hyphen_values_set() {
+            Ok(ParseResult::MaybeHyphenValue)
+        } else {
+            Ok(ParseResult::NoMatchingArg {
+                arg: long_arg.to_owned(),
+            })
+        }
+    }
+
+    fn parse_short_arg(
+        &mut self,
+        matcher: &mut ArgMatcher,
+        mut short_arg: clap_lex::ShortFlags<'_>,
+        parse_state: &ParseState,
+        // change this to possible pos_arg when removing the usage of &mut Parser.
+        pos_counter: usize,
+        valid_arg_found: &mut bool,
+        trailing_values: bool,
+    ) -> ClapResult<ParseResult> {
+        debug!("Parser::parse_short_arg: short_arg={:?}", short_arg);
+
+        #[allow(clippy::blocks_in_if_conditions)]
+        if self.cmd.is_allow_negative_numbers_set() && short_arg.is_number() {
+            debug!("Parser::parse_short_arg: negative number");
+            return Ok(ParseResult::MaybeHyphenValue);
+        } else if self.cmd.is_allow_hyphen_values_set()
+            && short_arg
+                .clone()
+                .any(|c| !c.map(|c| self.cmd.contains_short(c)).unwrap_or_default())
+        {
+            debug!("Parser::parse_short_args: contains non-short flag");
+            return Ok(ParseResult::MaybeHyphenValue);
+        } else if matches!(parse_state, ParseState::Opt(opt) | ParseState::Pos(opt)
+                if self.cmd[opt].is_allow_hyphen_values_set())
+        {
+            debug!("Parser::parse_short_args: prior arg accepts hyphenated values",);
+            return Ok(ParseResult::MaybeHyphenValue);
+        } else if self
+            .cmd
+            .get_keymap()
+            .get(&pos_counter)
+            .map_or(false, |arg| {
+                arg.is_allow_hyphen_values_set() && !arg.is_last_set()
+            })
+        {
+            debug!(
+                "Parser::parse_short_args: positional at {} allows hyphens",
+                pos_counter
+            );
+            return Ok(ParseResult::MaybeHyphenValue);
+        }
+
+        let mut ret = ParseResult::NoArg;
+
+        let skip = self.flag_subcmd_skip;
+        self.flag_subcmd_skip = 0;
+        let res = short_arg.advance_by(skip);
+        debug_assert_eq!(
+            res,
+            Ok(()),
+            "tracking of `flag_subcmd_skip` is off for `{:?}`",
+            short_arg
+        );
+        while let Some(c) = short_arg.next_flag() {
+            let c = match c {
+                Ok(c) => c,
+                Err(rest) => {
+                    return Ok(ParseResult::NoMatchingArg {
+                        arg: format!("-{}", rest.to_str_lossy()),
+                    });
+                }
+            };
+            debug!("Parser::parse_short_arg:iter:{}", c);
+
+            // Check for matching short options, and return the name if there is no trailing
+            // concatenated value: -oval
+            // Option: -o
+            // Value: val
+            if let Some(arg) = self.cmd.get_keymap().get(&c) {
+                let ident = Identifier::Short;
+                debug!(
+                    "Parser::parse_short_arg:iter:{}: Found valid opt or flag",
+                    c
+                );
+                *valid_arg_found = true;
+                if !arg.is_takes_value_set() {
+                    ret =
+                        self.react(Some(ident), ValueSource::CommandLine, arg, vec![], matcher)?;
+                    continue;
+                }
+
+                // Check for trailing concatenated value
+                //
+                // Cloning the iterator, so we rollback if it isn't there.
+                let val = short_arg.clone().next_value_os().unwrap_or_default();
+                debug!(
+                    "Parser::parse_short_arg:iter:{}: val={:?} (bytes), val={:?} (ascii), short_arg={:?}",
+                    c, val, val.as_raw_bytes(), short_arg
+                );
+                let val = Some(val).filter(|v| !v.is_empty());
+
+                // Default to "we're expecting a value later".
+                //
+                // If attached value is not consumed, we may have more short
+                // flags to parse, continue.
+                //
+                // e.g. `-xvf`, when require_equals && x.min_vals == 0, we don't
+                // consume the `vf`, even if it's provided as value.
+                let (val, has_eq) = if let Some(val) = val.and_then(|v| v.strip_prefix('=')) {
+                    (Some(val), true)
+                } else {
+                    (val, false)
+                };
+                match self.parse_opt_value(ident, val, arg, matcher, trailing_values, has_eq)? {
+                    ParseResult::AttachedValueNotConsumed => continue,
+                    x => return Ok(x),
+                }
+            }
+
+            return if let Some(sc_name) = self.cmd.find_short_subcmd(c) {
+                debug!("Parser::parse_short_arg:iter:{}: subcommand={}", c, sc_name);
+                // Make sure indices get updated before reading `self.cur_idx`
+                self.resolve_pending(matcher)?;
+                self.cur_idx.set(self.cur_idx.get() + 1);
+                debug!("Parser::parse_short_arg: cur_idx:={}", self.cur_idx.get());
+
+                let name = sc_name.to_string();
+                // Get the index of the previously saved flag subcommand in the group of flags (if exists).
+                // If it is a new flag subcommand, then the formentioned index should be the current one
+                // (ie. `cur_idx`), and should be registered.
+                let cur_idx = self.cur_idx.get();
+                self.flag_subcmd_at.get_or_insert(cur_idx);
+                let done_short_args = short_arg.is_empty();
+                if done_short_args {
+                    self.flag_subcmd_at = None;
+                }
+                Ok(ParseResult::FlagSubCommand(name))
+            } else {
+                Ok(ParseResult::NoMatchingArg {
+                    arg: format!("-{}", c),
+                })
+            };
+        }
+        Ok(ret)
+    }
+
+    fn parse_opt_value(
+        &self,
+        ident: Identifier,
+        attached_value: Option<&RawOsStr>,
+        arg: &Arg<'help>,
+        matcher: &mut ArgMatcher,
+        trailing_values: bool,
+        has_eq: bool,
+    ) -> ClapResult<ParseResult> {
+        debug!(
+            "Parser::parse_opt_value; arg={}, val={:?}, has_eq={:?}",
+            arg.name, attached_value, has_eq
+        );
+        debug!("Parser::parse_opt_value; arg.settings={:?}", arg.settings);
+
+        debug!("Parser::parse_opt_value; Checking for val...");
+        // require_equals is set, but no '=' is provided, try throwing error.
+        if arg.is_require_equals_set() && !has_eq {
+            if arg.min_vals == Some(0) {
+                debug!("Requires equals, but min_vals == 0");
+                let mut arg_values = Vec::new();
+                // We assume this case is valid: require equals, but min_vals == 0.
+                if !arg.default_missing_vals.is_empty() {
+                    debug!("Parser::parse_opt_value: has default_missing_vals");
+                    for v in arg.default_missing_vals.iter() {
+                        let trailing_values = false; // CLI should not be affecting default_missing_values
+                        let _parse_result = self.split_arg_values(
+                            arg,
+                            &RawOsStr::new(v),
+                            trailing_values,
+                            &mut arg_values,
+                        );
+                        if let Some(_parse_result) = _parse_result {
+                            if _parse_result != ParseResult::ValuesDone {
+                                debug!("Parser::parse_opt_value: Ignoring state {:?}; no values accepted after default_missing_values", _parse_result);
+                            }
+                        }
+                    }
+                };
+                let react_result = self.react(
+                    Some(ident),
+                    ValueSource::CommandLine,
+                    arg,
+                    arg_values,
+                    matcher,
+                )?;
+                debug_assert_eq!(react_result, ParseResult::ValuesDone);
+                if attached_value.is_some() {
+                    Ok(ParseResult::AttachedValueNotConsumed)
+                } else {
+                    Ok(ParseResult::ValuesDone)
+                }
+            } else {
+                debug!("Requires equals but not provided. Error.");
+                Ok(ParseResult::EqualsNotProvided {
+                    arg: arg.to_string(),
+                })
+            }
+        } else if let Some(v) = attached_value {
+            let mut arg_values = Vec::new();
+            let parse_result = self.split_arg_values(arg, v, trailing_values, &mut arg_values);
+            let react_result = self.react(
+                Some(ident),
+                ValueSource::CommandLine,
+                arg,
+                arg_values,
+                matcher,
+            )?;
+            debug_assert_eq!(react_result, ParseResult::ValuesDone);
+            let mut parse_result = parse_result.unwrap_or_else(|| {
+                if matcher.needs_more_vals(arg) {
+                    ParseResult::Opt(arg.id.clone())
+                } else {
+                    ParseResult::ValuesDone
+                }
+            });
+            if parse_result != ParseResult::ValuesDone {
+                debug!("Parser::parse_opt_value: Overriding state {:?}; no values accepted after attached", parse_result);
+                parse_result = ParseResult::ValuesDone;
+            }
+            Ok(parse_result)
+        } else {
+            debug!("Parser::parse_opt_value: More arg vals required...");
+            self.resolve_pending(matcher)?;
+            matcher.pending_values_mut(&arg.id, Some(ident));
+            Ok(ParseResult::Opt(arg.id.clone()))
+        }
+    }
+
+    fn split_arg_values(
+        &self,
+        arg: &Arg<'help>,
+        val: &RawOsStr,
+        trailing_values: bool,
+        output: &mut Vec<OsString>,
+    ) -> Option<ParseResult> {
+        debug!("Parser::split_arg_values; arg={}, val={:?}", arg.name, val);
+        debug!(
+            "Parser::split_arg_values; trailing_values={:?}, DontDelimTrailingVals={:?}",
+            trailing_values,
+            self.cmd.is_dont_delimit_trailing_values_set()
+        );
+
+        let mut delim = arg.val_delim;
+        if trailing_values && self.cmd.is_dont_delimit_trailing_values_set() {
+            delim = None;
+        }
+        match delim {
+            Some(delim) if val.contains(delim) => {
+                let vals = val.split(delim).map(|x| x.to_os_str().into_owned());
+                for raw_val in vals {
+                    if Some(raw_val.as_os_str()) == arg.terminator.map(OsStr::new) {
+                        return Some(ParseResult::ValuesDone);
+                    }
+                    output.push(raw_val);
+                }
+                // Delimited values are always considered the final value
+                Some(ParseResult::ValuesDone)
+            }
+            _ if Some(val) == arg.terminator.map(RawOsStr::from_str) => {
+                Some(ParseResult::ValuesDone)
+            }
+            _ => {
+                output.push(val.to_os_str().into_owned());
+                if arg.is_require_value_delimiter_set() {
+                    Some(ParseResult::ValuesDone)
+                } else {
+                    None
+                }
+            }
+        }
+    }
+
+    fn push_arg_values(
+        &self,
+        arg: &Arg<'help>,
+        raw_vals: Vec<OsString>,
+        matcher: &mut ArgMatcher,
+    ) -> ClapResult<()> {
+        debug!("Parser::push_arg_values: {:?}", raw_vals);
+
+        for raw_val in raw_vals {
+            // update the current index because each value is a distinct index to clap
+            self.cur_idx.set(self.cur_idx.get() + 1);
+            debug!(
+                "Parser::add_single_val_to_arg: cur_idx:={}",
+                self.cur_idx.get()
+            );
+            let value_parser = arg.get_value_parser();
+            let val = value_parser.parse_ref(self.cmd, Some(arg), &raw_val)?;
+
+            // Increment or create the group "args"
+            for group in self.cmd.groups_for_arg(&arg.id) {
+                matcher.add_val_to(&group, val.clone(), raw_val.clone());
+            }
+
+            matcher.add_val_to(&arg.id, val, raw_val);
+            matcher.add_index_to(&arg.id, self.cur_idx.get());
+        }
+
+        Ok(())
+    }
+
+    fn resolve_pending(&self, matcher: &mut ArgMatcher) -> ClapResult<()> {
+        let pending = match matcher.take_pending() {
+            Some(pending) => pending,
+            None => {
+                return Ok(());
+            }
+        };
+
+        debug!("Parser::resolve_pending: id={:?}", pending.id);
+        let arg = self.cmd.find(&pending.id).expect(INTERNAL_ERROR_MSG);
+        let _ = self.react(
+            pending.ident,
+            ValueSource::CommandLine,
+            arg,
+            pending.raw_vals,
+            matcher,
+        )?;
+
+        Ok(())
+    }
+
+    fn react(
+        &self,
+        ident: Option<Identifier>,
+        source: ValueSource,
+        arg: &Arg<'help>,
+        raw_vals: Vec<OsString>,
+        matcher: &mut ArgMatcher,
+    ) -> ClapResult<ParseResult> {
+        self.resolve_pending(matcher)?;
+
+        debug!(
+            "Parser::react action={:?}, identifier={:?}, source={:?}",
+            arg.get_action(),
+            ident,
+            source
+        );
+        match arg.get_action() {
+            ArgAction::Set => {
+                if source == ValueSource::CommandLine
+                    && matches!(ident, Some(Identifier::Short) | Some(Identifier::Long))
+                {
+                    // Record flag's index
+                    self.cur_idx.set(self.cur_idx.get() + 1);
+                    debug!("Parser::react: cur_idx:={}", self.cur_idx.get());
+                }
+                matcher.remove(&arg.id);
+                self.start_custom_arg(matcher, arg, source);
+                self.push_arg_values(arg, raw_vals, matcher)?;
+                if cfg!(debug_assertions) && matcher.needs_more_vals(arg) {
+                    debug!(
+                        "Parser::react not enough values passed in, leaving it to the validator to complain",
+                    );
+                }
+                Ok(ParseResult::ValuesDone)
+            }
+            ArgAction::Append => {
+                if source == ValueSource::CommandLine
+                    && matches!(ident, Some(Identifier::Short) | Some(Identifier::Long))
+                {
+                    // Record flag's index
+                    self.cur_idx.set(self.cur_idx.get() + 1);
+                    debug!("Parser::react: cur_idx:={}", self.cur_idx.get());
+                }
+                self.start_custom_arg(matcher, arg, source);
+                self.push_arg_values(arg, raw_vals, matcher)?;
+                if cfg!(debug_assertions) && matcher.needs_more_vals(arg) {
+                    debug!(
+                        "Parser::react not enough values passed in, leaving it to the validator to complain",
+                    );
+                }
+                Ok(ParseResult::ValuesDone)
+            }
+            #[allow(deprecated)]
+            ArgAction::StoreValue => {
+                if ident == Some(Identifier::Index)
+                    && arg.is_multiple_values_set()
+                    && matcher.contains(&arg.id)
+                {
+                    // HACK: Reuse existing occurrence
+                } else if source == ValueSource::CommandLine {
+                    if matches!(ident, Some(Identifier::Short) | Some(Identifier::Long)) {
+                        // Record flag's index
+                        self.cur_idx.set(self.cur_idx.get() + 1);
+                        debug!("Parser::react: cur_idx:={}", self.cur_idx.get());
+                    }
+                    self.start_occurrence_of_arg(matcher, arg);
+                } else {
+                    self.start_custom_arg(matcher, arg, source);
+                }
+                self.push_arg_values(arg, raw_vals, matcher)?;
+                if ident == Some(Identifier::Index) && arg.is_multiple_values_set() {
+                    // HACK: Maintain existing occurrence behavior
+                    let matched = matcher.get_mut(&arg.id).unwrap();
+                    #[allow(deprecated)]
+                    matched.set_occurrences(matched.num_vals() as u64);
+                }
+                if cfg!(debug_assertions) && matcher.needs_more_vals(arg) {
+                    debug!(
+                        "Parser::react not enough values passed in, leaving it to the validator to complain",
+                    );
+                }
+                Ok(ParseResult::ValuesDone)
+            }
+            #[allow(deprecated)]
+            ArgAction::IncOccurrence => {
+                debug_assert_eq!(raw_vals, Vec::<OsString>::new());
+                if source == ValueSource::CommandLine {
+                    if matches!(ident, Some(Identifier::Short) | Some(Identifier::Long)) {
+                        // Record flag's index
+                        self.cur_idx.set(self.cur_idx.get() + 1);
+                        debug!("Parser::react: cur_idx:={}", self.cur_idx.get());
+                    }
+                    self.start_occurrence_of_arg(matcher, arg);
+                } else {
+                    self.start_custom_arg(matcher, arg, source);
+                }
+                matcher.add_index_to(&arg.id, self.cur_idx.get());
+                Ok(ParseResult::ValuesDone)
+            }
+            ArgAction::SetTrue => {
+                let raw_vals = match raw_vals.len() {
+                    0 => {
+                        vec![OsString::from("true")]
+                    }
+                    1 => raw_vals,
+                    _ => {
+                        debug!("Parser::react ignoring trailing values: {:?}", raw_vals);
+                        let mut raw_vals = raw_vals;
+                        raw_vals.resize(1, Default::default());
+                        raw_vals
+                    }
+                };
+
+                matcher.remove(&arg.id);
+                self.start_custom_arg(matcher, arg, source);
+                self.push_arg_values(arg, raw_vals, matcher)?;
+                Ok(ParseResult::ValuesDone)
+            }
+            ArgAction::SetFalse => {
+                let raw_vals = match raw_vals.len() {
+                    0 => {
+                        vec![OsString::from("false")]
+                    }
+                    1 => raw_vals,
+                    _ => {
+                        debug!("Parser::react ignoring trailing values: {:?}", raw_vals);
+                        let mut raw_vals = raw_vals;
+                        raw_vals.resize(1, Default::default());
+                        raw_vals
+                    }
+                };
+
+                matcher.remove(&arg.id);
+                self.start_custom_arg(matcher, arg, source);
+                self.push_arg_values(arg, raw_vals, matcher)?;
+                Ok(ParseResult::ValuesDone)
+            }
+            ArgAction::Count => {
+                let raw_vals = match raw_vals.len() {
+                    0 => {
+                        let existing_value = *matcher
+                            .get_one::<crate::builder::CountType>(arg.get_id())
+                            .unwrap_or(&0);
+                        let next_value = existing_value.saturating_add(1);
+                        vec![OsString::from(next_value.to_string())]
+                    }
+                    1 => raw_vals,
+                    _ => {
+                        debug!("Parser::react ignoring trailing values: {:?}", raw_vals);
+                        let mut raw_vals = raw_vals;
+                        raw_vals.resize(1, Default::default());
+                        raw_vals
+                    }
+                };
+
+                matcher.remove(&arg.id);
+                self.start_custom_arg(matcher, arg, source);
+                self.push_arg_values(arg, raw_vals, matcher)?;
+                Ok(ParseResult::ValuesDone)
+            }
+            ArgAction::Help => {
+                debug_assert_eq!(raw_vals, Vec::<OsString>::new());
+                let use_long = match ident {
+                    Some(Identifier::Long) => true,
+                    Some(Identifier::Short) => false,
+                    Some(Identifier::Index) => true,
+                    None => true,
+                };
+                debug!("Help: use_long={}", use_long);
+                Err(self.help_err(use_long, Stream::Stdout))
+            }
+            ArgAction::Version => {
+                debug_assert_eq!(raw_vals, Vec::<OsString>::new());
+                let use_long = match ident {
+                    Some(Identifier::Long) => true,
+                    Some(Identifier::Short) => false,
+                    Some(Identifier::Index) => true,
+                    None => true,
+                };
+                debug!("Version: use_long={}", use_long);
+                Err(self.version_err(use_long))
+            }
+        }
+    }
+
+    fn remove_overrides(&self, arg: &Arg<'help>, matcher: &mut ArgMatcher) {
+        debug!("Parser::remove_overrides: id={:?}", arg.id);
+        for override_id in &arg.overrides {
+            debug!("Parser::remove_overrides:iter:{:?}: removing", override_id);
+            matcher.remove(override_id);
+        }
+
+        // Override anything that can override us
+        let mut transitive = Vec::new();
+        for arg_id in matcher.arg_ids() {
+            if let Some(overrider) = self.cmd.find(arg_id) {
+                if overrider.overrides.contains(&arg.id) {
+                    transitive.push(&overrider.id);
+                }
+            }
+        }
+        for overrider_id in transitive {
+            debug!("Parser::remove_overrides:iter:{:?}: removing", overrider_id);
+            matcher.remove(overrider_id);
+        }
+    }
+
+    #[cfg(feature = "env")]
+    fn add_env(&mut self, matcher: &mut ArgMatcher) -> ClapResult<()> {
+        debug!("Parser::add_env");
+        use crate::util::str_to_bool;
+
+        let trailing_values = false; // defaults are independent of the commandline
+        for arg in self.cmd.get_arguments() {
+            // Use env only if the arg was absent among command line args,
+            // early return if this is not the case.
+            if matcher.contains(&arg.id) {
+                debug!("Parser::add_env: Skipping existing arg `{}`", arg);
+                continue;
+            }
+
+            debug!("Parser::add_env: Checking arg `{}`", arg);
+            if let Some((_, Some(ref val))) = arg.env {
+                let val = RawOsStr::new(val);
+
+                if arg.is_takes_value_set() {
+                    debug!(
+                        "Parser::add_env: Found an opt with value={:?}, trailing={:?}",
+                        val, trailing_values
+                    );
+                    let mut arg_values = Vec::new();
+                    let _parse_result =
+                        self.split_arg_values(arg, &val, trailing_values, &mut arg_values);
+                    let _ = self.react(None, ValueSource::EnvVariable, arg, arg_values, matcher)?;
+                    if let Some(_parse_result) = _parse_result {
+                        if _parse_result != ParseResult::ValuesDone {
+                            debug!("Parser::add_env: Ignoring state {:?}; env variables are outside of the parse loop", _parse_result);
+                        }
+                    }
+                } else {
+                    match arg.get_action() {
+                        #[allow(deprecated)]
+                        ArgAction::StoreValue => unreachable!("{:?} is not a flag", arg.get_id()),
+                        #[allow(deprecated)]
+                        ArgAction::IncOccurrence => {
+                            debug!("Parser::add_env: Found a flag with value `{:?}`", val);
+                            let predicate = str_to_bool(val.to_str_lossy());
+                            debug!("Parser::add_env: Found boolean literal `{:?}`", predicate);
+                            if predicate.unwrap_or(true) {
+                                let _ = self.react(
+                                    None,
+                                    ValueSource::EnvVariable,
+                                    arg,
+                                    vec![],
+                                    matcher,
+                                )?;
+                            }
+                        }
+                        ArgAction::Set
+                        | ArgAction::Append
+                        | ArgAction::SetTrue
+                        | ArgAction::SetFalse
+                        | ArgAction::Count => {
+                            let mut arg_values = Vec::new();
+                            let _parse_result =
+                                self.split_arg_values(arg, &val, trailing_values, &mut arg_values);
+                            let _ = self.react(
+                                None,
+                                ValueSource::EnvVariable,
+                                arg,
+                                arg_values,
+                                matcher,
+                            )?;
+                            if let Some(_parse_result) = _parse_result {
+                                if _parse_result != ParseResult::ValuesDone {
+                                    debug!("Parser::add_env: Ignoring state {:?}; env variables are outside of the parse loop", _parse_result);
+                                }
+                            }
+                        }
+                        // Early return on `Help` or `Version`.
+                        ArgAction::Help | ArgAction::Version => {
+                            let _ =
+                                self.react(None, ValueSource::EnvVariable, arg, vec![], matcher)?;
+                        }
+                    }
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    fn add_defaults(&self, matcher: &mut ArgMatcher) -> ClapResult<()> {
+        debug!("Parser::add_defaults");
+
+        for arg in self.cmd.get_arguments() {
+            debug!("Parser::add_defaults:iter:{}:", arg.name);
+            self.add_default_value(arg, matcher)?;
+        }
+
+        Ok(())
+    }
+
+    fn add_default_value(&self, arg: &Arg<'help>, matcher: &mut ArgMatcher) -> ClapResult<()> {
+        let trailing_values = false; // defaults are independent of the commandline
+
+        if !arg.default_missing_vals.is_empty() {
+            debug!(
+                "Parser::add_default_value:iter:{}: has default missing vals",
+                arg.name
+            );
+            match matcher.get(&arg.id) {
+                Some(ma) if ma.all_val_groups_empty() => {
+                    debug!(
+                        "Parser::add_default_value:iter:{}: has no user defined vals",
+                        arg.name
+                    );
+                    // The flag occurred, we just want to add the val groups
+                    let mut arg_values = Vec::new();
+                    for v in arg.default_missing_vals.iter() {
+                        let _parse_result = self.split_arg_values(
+                            arg,
+                            &RawOsStr::new(v),
+                            trailing_values,
+                            &mut arg_values,
+                        );
+                        if let Some(_parse_result) = _parse_result {
+                            if _parse_result != ParseResult::ValuesDone {
+                                debug!("Parser::add_default_value: Ignoring state {:?}; defaults are outside of the parse loop", _parse_result);
+                            }
+                        }
+                    }
+                    self.start_custom_arg(matcher, arg, ValueSource::CommandLine);
+                    self.push_arg_values(arg, arg_values, matcher)?;
+                }
+                None => {
+                    debug!("Parser::add_default_value:iter:{}: wasn't used", arg.name);
+                    // do nothing
+                }
+                _ => {
+                    debug!(
+                        "Parser::add_default_value:iter:{}: has user defined vals",
+                        arg.name
+                    );
+                    // do nothing
+                }
+            }
+        } else {
+            debug!(
+                "Parser::add_default_value:iter:{}: doesn't have default missing vals",
+                arg.name
+            );
+            // do nothing
+        }
+
+        if !arg.default_vals_ifs.is_empty() {
+            debug!("Parser::add_default_value: has conditional defaults");
+            if !matcher.contains(&arg.id) {
+                for (id, val, default) in arg.default_vals_ifs.iter() {
+                    let add = if let Some(a) = matcher.get(id) {
+                        match val {
+                            crate::builder::ArgPredicate::Equals(v) => {
+                                a.raw_vals_flatten().any(|value| v == value)
+                            }
+                            crate::builder::ArgPredicate::IsPresent => true,
+                        }
+                    } else {
+                        false
+                    };
+
+                    if add {
+                        if let Some(default) = default {
+                            let mut arg_values = Vec::new();
+                            let _parse_result = self.split_arg_values(
+                                arg,
+                                &RawOsStr::new(default),
+                                trailing_values,
+                                &mut arg_values,
+                            );
+                            let _ = self.react(
+                                None,
+                                ValueSource::DefaultValue,
+                                arg,
+                                arg_values,
+                                matcher,
+                            )?;
+                            if let Some(_parse_result) = _parse_result {
+                                if _parse_result != ParseResult::ValuesDone {
+                                    debug!("Parser::add_default_value: Ignoring state {:?}; defaults are outside of the parse loop", _parse_result);
+                                }
+                            }
+                        }
+                        return Ok(());
+                    }
+                }
+            }
+        } else {
+            debug!("Parser::add_default_value: doesn't have conditional defaults");
+        }
+
+        if !arg.default_vals.is_empty() {
+            debug!(
+                "Parser::add_default_value:iter:{}: has default vals",
+                arg.name
+            );
+            if matcher.contains(&arg.id) {
+                debug!("Parser::add_default_value:iter:{}: was used", arg.name);
+            // do nothing
+            } else {
+                debug!("Parser::add_default_value:iter:{}: wasn't used", arg.name);
+                let mut arg_values = Vec::new();
+                for v in arg.default_vals.iter() {
+                    let _parse_result = self.split_arg_values(
+                        arg,
+                        &RawOsStr::new(v),
+                        trailing_values,
+                        &mut arg_values,
+                    );
+                    if let Some(_parse_result) = _parse_result {
+                        if _parse_result != ParseResult::ValuesDone {
+                            debug!("Parser::add_default_value: Ignoring state {:?}; defaults are outside of the parse loop", _parse_result);
+                        }
+                    }
+                }
+                let _ = self.react(None, ValueSource::DefaultValue, arg, arg_values, matcher)?;
+            }
+        } else {
+            debug!(
+                "Parser::add_default_value:iter:{}: doesn't have default vals",
+                arg.name
+            );
+
+            // do nothing
+        }
+
+        Ok(())
+    }
+
+    fn start_custom_arg(&self, matcher: &mut ArgMatcher, arg: &Arg<'help>, source: ValueSource) {
+        if source == ValueSource::CommandLine {
+            // With each new occurrence, remove overrides from prior occurrences
+            self.remove_overrides(arg, matcher);
+        }
+        matcher.start_custom_arg(arg, source);
+        for group in self.cmd.groups_for_arg(&arg.id) {
+            matcher.start_custom_group(&group, source);
+        }
+    }
+
+    /// Increase occurrence of specific argument and the grouped arg it's in.
+    fn start_occurrence_of_arg(&self, matcher: &mut ArgMatcher, arg: &Arg<'help>) {
+        // With each new occurrence, remove overrides from prior occurrences
+        self.remove_overrides(arg, matcher);
+
+        matcher.start_occurrence_of_arg(arg);
+        // Increment or create the group "args"
+        for group in self.cmd.groups_for_arg(&arg.id) {
+            matcher.start_occurrence_of_group(&group);
+        }
+    }
+}
+
+// Error, Help, and Version Methods
+impl<'help, 'cmd> Parser<'help, 'cmd> {
+    /// Is only used for the long flag(which is the only one needs fuzzy searching)
+    fn did_you_mean_error(
+        &mut self,
+        arg: &str,
+        matcher: &mut ArgMatcher,
+        remaining_args: &[&str],
+    ) -> ClapError {
+        debug!("Parser::did_you_mean_error: arg={}", arg);
+        // Didn't match a flag or option
+        let longs = self
+            .cmd
+            .get_keymap()
+            .keys()
+            .filter_map(|x| match x {
+                KeyType::Long(l) => Some(l.to_string_lossy().into_owned()),
+                _ => None,
+            })
+            .collect::<Vec<_>>();
+        debug!("Parser::did_you_mean_error: longs={:?}", longs);
+
+        let did_you_mean = suggestions::did_you_mean_flag(
+            arg,
+            remaining_args,
+            longs.iter().map(|x| &x[..]),
+            self.cmd.get_subcommands_mut(),
+        );
+
+        // Add the arg to the matches to build a proper usage string
+        if let Some((name, _)) = did_you_mean.as_ref() {
+            if let Some(arg) = self.cmd.get_keymap().get(&name.as_ref()) {
+                self.start_occurrence_of_arg(matcher, arg);
+            }
+        }
+
+        let required = self.cmd.required_graph();
+        let used: Vec<Id> = matcher
+            .arg_ids()
+            .filter(|arg_id| {
+                matcher.check_explicit(arg_id, crate::builder::ArgPredicate::IsPresent)
+            })
+            .filter(|n| self.cmd.find(n).map_or(true, |a| !a.is_hide_set()))
+            .cloned()
+            .collect();
+
+        ClapError::unknown_argument(
+            self.cmd,
+            format!("--{}", arg),
+            did_you_mean,
+            Usage::new(self.cmd)
+                .required(&required)
+                .create_usage_with_title(&*used),
+        )
+    }
+
+    fn help_err(&self, use_long: bool, stream: Stream) -> ClapError {
+        match self.cmd.write_help_err(use_long, stream) {
+            Ok(c) => ClapError::display_help(self.cmd, c),
+            Err(e) => e,
+        }
+    }
+
+    fn version_err(&self, use_long: bool) -> ClapError {
+        debug!("Parser::version_err");
+
+        let msg = self.cmd._render_version(use_long);
+        let mut c = Colorizer::new(Stream::Stdout, self.cmd.color_help());
+        c.none(msg);
+        ClapError::display_version(self.cmd, c)
+    }
+}
+
+// Query Methods
+impl<'help, 'cmd> Parser<'help, 'cmd> {
+    pub(crate) fn is_set(&self, s: AS) -> bool {
+        self.cmd.is_set(s)
+    }
+}
+
+#[derive(Debug, PartialEq, Eq)]
+pub(crate) enum ParseState {
+    ValuesDone,
+    Opt(Id),
+    Pos(Id),
+}
+
+/// Recoverable Parsing results.
+#[derive(Debug, PartialEq, Clone)]
+#[must_use]
+enum ParseResult {
+    FlagSubCommand(String),
+    Opt(Id),
+    ValuesDone,
+    /// Value attached to the short flag is not consumed(e.g. 'u' for `-cu` is
+    /// not consumed).
+    AttachedValueNotConsumed,
+    /// This long flag doesn't need a value but is provided one.
+    UnneededAttachedValue {
+        rest: String,
+        used: Vec<Id>,
+        arg: String,
+    },
+    /// This flag might be an hyphen Value.
+    MaybeHyphenValue,
+    /// Equals required but not provided.
+    EqualsNotProvided {
+        arg: String,
+    },
+    /// Failed to match a Arg.
+    NoMatchingArg {
+        arg: String,
+    },
+    /// No argument found e.g. parser is given `-` when parsing a flag.
+    NoArg,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(crate) struct PendingArg {
+    pub(crate) id: Id,
+    pub(crate) ident: Option<Identifier>,
+    pub(crate) raw_vals: Vec<OsString>,
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub(crate) enum Identifier {
+    Short,
+    Long,
+    Index,
+}
diff --git a/vendor/clap-3.2.20/src/parser/validator.rs b/vendor/clap-3.2.20/src/parser/validator.rs
new file mode 100644
index 000000000..ebf2b234d
--- /dev/null
+++ b/vendor/clap-3.2.20/src/parser/validator.rs
@@ -0,0 +1,692 @@
+// Internal
+use crate::builder::{AppSettings, Arg, ArgPredicate, Command, PossibleValue};
+use crate::error::{Error, Result as ClapResult};
+use crate::output::fmt::Stream;
+use crate::output::Usage;
+use crate::parser::{ArgMatcher, MatchedArg, ParseState};
+use crate::util::ChildGraph;
+use crate::util::Id;
+use crate::{INTERNAL_ERROR_MSG, INVALID_UTF8};
+
+pub(crate) struct Validator<'help, 'cmd> {
+    cmd: &'cmd Command<'help>,
+    required: ChildGraph<Id>,
+}
+
+impl<'help, 'cmd> Validator<'help, 'cmd> {
+    pub(crate) fn new(cmd: &'cmd Command<'help>) -> Self {
+        let required = cmd.required_graph();
+        Validator { cmd, required }
+    }
+
+    pub(crate) fn validate(
+        &mut self,
+        parse_state: ParseState,
+        matcher: &mut ArgMatcher,
+    ) -> ClapResult<()> {
+        debug!("Validator::validate");
+        let mut conflicts = Conflicts::new();
+        let has_subcmd = matcher.subcommand_name().is_some();
+
+        if let ParseState::Opt(a) = parse_state {
+            debug!("Validator::validate: needs_val_of={:?}", a);
+
+            let o = &self.cmd[&a];
+            let should_err = if let Some(v) = matcher.args.get(&o.id) {
+                v.all_val_groups_empty() && !(o.min_vals.is_some() && o.min_vals.unwrap() == 0)
+            } else {
+                true
+            };
+            if should_err {
+                return Err(Error::empty_value(
+                    self.cmd,
+                    &get_possible_values(o)
+                        .iter()
+                        .filter(|pv| !pv.is_hide_set())
+                        .map(PossibleValue::get_name)
+                        .collect::<Vec<_>>(),
+                    o.to_string(),
+                ));
+            }
+        }
+
+        if !has_subcmd && self.cmd.is_arg_required_else_help_set() {
+            let num_user_values = matcher
+                .arg_ids()
+                .filter(|arg_id| matcher.check_explicit(arg_id, ArgPredicate::IsPresent))
+                .count();
+            if num_user_values == 0 {
+                let message = self.cmd.write_help_err(false, Stream::Stderr)?;
+                return Err(Error::display_help_error(self.cmd, message));
+            }
+        }
+        #[allow(deprecated)]
+        if !has_subcmd && self.cmd.is_subcommand_required_set() {
+            let bn = self
+                .cmd
+                .get_bin_name()
+                .unwrap_or_else(|| self.cmd.get_name());
+            return Err(Error::missing_subcommand(
+                self.cmd,
+                bn.to_string(),
+                Usage::new(self.cmd)
+                    .required(&self.required)
+                    .create_usage_with_title(&[]),
+            ));
+        } else if !has_subcmd && self.cmd.is_set(AppSettings::SubcommandRequiredElseHelp) {
+            debug!("Validator::new::get_matches_with: SubcommandRequiredElseHelp=true");
+            let message = self.cmd.write_help_err(false, Stream::Stderr)?;
+            return Err(Error::display_help_error(self.cmd, message));
+        }
+
+        self.validate_conflicts(matcher, &mut conflicts)?;
+        if !(self.cmd.is_subcommand_negates_reqs_set() && has_subcmd) {
+            self.validate_required(matcher, &mut conflicts)?;
+        }
+        self.validate_matched_args(matcher)?;
+
+        Ok(())
+    }
+
+    fn validate_arg_values(&self, arg: &Arg, ma: &MatchedArg) -> ClapResult<()> {
+        debug!("Validator::validate_arg_values: arg={:?}", arg.name);
+        for val in ma.raw_vals_flatten() {
+            if !arg.possible_vals.is_empty() {
+                debug!(
+                    "Validator::validate_arg_values: possible_vals={:?}",
+                    arg.possible_vals
+                );
+                let val_str = val.to_string_lossy();
+                let ok = arg
+                    .possible_vals
+                    .iter()
+                    .any(|pv| pv.matches(&val_str, arg.is_ignore_case_set()));
+                if !ok {
+                    return Err(Error::invalid_value(
+                        self.cmd,
+                        val_str.into_owned(),
+                        &arg.possible_vals
+                            .iter()
+                            .filter(|pv| !pv.is_hide_set())
+                            .map(PossibleValue::get_name)
+                            .collect::<Vec<_>>(),
+                        arg.to_string(),
+                    ));
+                }
+            }
+            {
+                #![allow(deprecated)]
+                if arg.is_forbid_empty_values_set() && val.is_empty() {
+                    debug!("Validator::validate_arg_values: illegal empty val found");
+                    return Err(Error::empty_value(
+                        self.cmd,
+                        &get_possible_values(arg)
+                            .iter()
+                            .filter(|pv| !pv.is_hide_set())
+                            .map(PossibleValue::get_name)
+                            .collect::<Vec<_>>(),
+                        arg.to_string(),
+                    ));
+                }
+            }
+
+            if let Some(ref vtor) = arg.validator {
+                debug!("Validator::validate_arg_values: checking validator...");
+                let mut vtor = vtor.lock().unwrap();
+                if let Err(e) = vtor(&*val.to_string_lossy()) {
+                    debug!("error");
+                    return Err(Error::value_validation(
+                        arg.to_string(),
+                        val.to_string_lossy().into_owned(),
+                        e,
+                    )
+                    .with_cmd(self.cmd));
+                } else {
+                    debug!("good");
+                }
+            }
+            if let Some(ref vtor) = arg.validator_os {
+                debug!("Validator::validate_arg_values: checking validator_os...");
+                let mut vtor = vtor.lock().unwrap();
+                if let Err(e) = vtor(val) {
+                    debug!("error");
+                    return Err(Error::value_validation(
+                        arg.to_string(),
+                        val.to_string_lossy().into(),
+                        e,
+                    )
+                    .with_cmd(self.cmd));
+                } else {
+                    debug!("good");
+                }
+            }
+        }
+        Ok(())
+    }
+
+    fn validate_conflicts(
+        &mut self,
+        matcher: &ArgMatcher,
+        conflicts: &mut Conflicts,
+    ) -> ClapResult<()> {
+        debug!("Validator::validate_conflicts");
+
+        self.validate_exclusive(matcher)?;
+
+        for arg_id in matcher
+            .arg_ids()
+            .filter(|arg_id| matcher.check_explicit(arg_id, ArgPredicate::IsPresent))
+            .filter(|arg_id| self.cmd.find(arg_id).is_some())
+        {
+            debug!("Validator::validate_conflicts::iter: id={:?}", arg_id);
+            let conflicts = conflicts.gather_conflicts(self.cmd, matcher, arg_id);
+            self.build_conflict_err(arg_id, &conflicts, matcher)?;
+        }
+
+        Ok(())
+    }
+
+    fn validate_exclusive(&self, matcher: &ArgMatcher) -> ClapResult<()> {
+        debug!("Validator::validate_exclusive");
+        let args_count = matcher
+            .arg_ids()
+            .filter(|arg_id| {
+                matcher.check_explicit(arg_id, crate::builder::ArgPredicate::IsPresent)
+            })
+            .count();
+        if args_count <= 1 {
+            // Nothing present to conflict with
+            return Ok(());
+        }
+
+        matcher
+            .arg_ids()
+            .filter(|arg_id| {
+                matcher.check_explicit(arg_id, crate::builder::ArgPredicate::IsPresent)
+            })
+            .filter_map(|name| {
+                debug!("Validator::validate_exclusive:iter:{:?}", name);
+                self.cmd
+                    .find(name)
+                    // Find `arg`s which are exclusive but also appear with other args.
+                    .filter(|&arg| arg.is_exclusive_set() && args_count > 1)
+            })
+            // Throw an error for the first conflict found.
+            .try_for_each(|arg| {
+                Err(Error::argument_conflict(
+                    self.cmd,
+                    arg.to_string(),
+                    Vec::new(),
+                    Usage::new(self.cmd)
+                        .required(&self.required)
+                        .create_usage_with_title(&[]),
+                ))
+            })
+    }
+
+    fn build_conflict_err(
+        &self,
+        name: &Id,
+        conflict_ids: &[Id],
+        matcher: &ArgMatcher,
+    ) -> ClapResult<()> {
+        if conflict_ids.is_empty() {
+            return Ok(());
+        }
+
+        debug!("Validator::build_conflict_err: name={:?}", name);
+        let mut seen = std::collections::HashSet::new();
+        let conflicts = conflict_ids
+            .iter()
+            .flat_map(|c_id| {
+                if self.cmd.find_group(c_id).is_some() {
+                    self.cmd.unroll_args_in_group(c_id)
+                } else {
+                    vec![c_id.clone()]
+                }
+            })
+            .filter_map(|c_id| {
+                seen.insert(c_id.clone()).then(|| {
+                    let c_arg = self.cmd.find(&c_id).expect(INTERNAL_ERROR_MSG);
+                    c_arg.to_string()
+                })
+            })
+            .collect();
+
+        let former_arg = self.cmd.find(name).expect(INTERNAL_ERROR_MSG);
+        let usg = self.build_conflict_err_usage(matcher, conflict_ids);
+        Err(Error::argument_conflict(
+            self.cmd,
+            former_arg.to_string(),
+            conflicts,
+            usg,
+        ))
+    }
+
+    fn build_conflict_err_usage(&self, matcher: &ArgMatcher, conflicting_keys: &[Id]) -> String {
+        let used_filtered: Vec<Id> = matcher
+            .arg_ids()
+            .filter(|arg_id| matcher.check_explicit(arg_id, ArgPredicate::IsPresent))
+            .filter(|n| {
+                // Filter out the args we don't want to specify.
+                self.cmd.find(n).map_or(true, |a| !a.is_hide_set())
+            })
+            .filter(|key| !conflicting_keys.contains(key))
+            .cloned()
+            .collect();
+        let required: Vec<Id> = used_filtered
+            .iter()
+            .filter_map(|key| self.cmd.find(key))
+            .flat_map(|arg| arg.requires.iter().map(|item| &item.1))
+            .filter(|key| !used_filtered.contains(key) && !conflicting_keys.contains(key))
+            .chain(used_filtered.iter())
+            .cloned()
+            .collect();
+        Usage::new(self.cmd)
+            .required(&self.required)
+            .create_usage_with_title(&required)
+    }
+
+    fn gather_requires(&mut self, matcher: &ArgMatcher) {
+        debug!("Validator::gather_requires");
+        for name in matcher
+            .arg_ids()
+            .filter(|arg_id| matcher.check_explicit(arg_id, ArgPredicate::IsPresent))
+        {
+            debug!("Validator::gather_requires:iter:{:?}", name);
+            if let Some(arg) = self.cmd.find(name) {
+                let is_relevant = |(val, req_arg): &(ArgPredicate<'_>, Id)| -> Option<Id> {
+                    let required = matcher.check_explicit(&arg.id, *val);
+                    required.then(|| req_arg.clone())
+                };
+
+                for req in self.cmd.unroll_arg_requires(is_relevant, &arg.id) {
+                    self.required.insert(req);
+                }
+            } else if let Some(g) = self.cmd.find_group(name) {
+                debug!("Validator::gather_requires:iter:{:?}:group", name);
+                for r in &g.requires {
+                    self.required.insert(r.clone());
+                }
+            }
+        }
+    }
+
+    fn validate_matched_args(&self, matcher: &ArgMatcher) -> ClapResult<()> {
+        debug!("Validator::validate_matched_args");
+        matcher.iter().try_for_each(|(name, ma)| {
+            debug!(
+                "Validator::validate_matched_args:iter:{:?}: vals={:#?}",
+                name,
+                ma.vals_flatten()
+            );
+            if let Some(arg) = self.cmd.find(name) {
+                self.validate_arg_num_vals(arg, ma)?;
+                self.validate_arg_values(arg, ma)?;
+                self.validate_arg_num_occurs(arg, ma)?;
+            }
+            Ok(())
+        })
+    }
+
+    fn validate_arg_num_occurs(&self, a: &Arg, ma: &MatchedArg) -> ClapResult<()> {
+        #![allow(deprecated)]
+        debug!(
+            "Validator::validate_arg_num_occurs: {:?}={}",
+            a.name,
+            ma.get_occurrences()
+        );
+        // Occurrence of positional argument equals to number of values rather
+        // than number of grouped values.
+        if ma.get_occurrences() > 1 && !a.is_multiple_occurrences_set() && !a.is_positional() {
+            // Not the first time, and we don't allow multiples
+            return Err(Error::unexpected_multiple_usage(
+                self.cmd,
+                a.to_string(),
+                Usage::new(self.cmd)
+                    .required(&self.required)
+                    .create_usage_with_title(&[]),
+            ));
+        }
+        if let Some(max_occurs) = a.max_occurs {
+            debug!(
+                "Validator::validate_arg_num_occurs: max_occurs set...{}",
+                max_occurs
+            );
+            let occurs = ma.get_occurrences() as usize;
+            if occurs > max_occurs {
+                return Err(Error::too_many_occurrences(
+                    self.cmd,
+                    a.to_string(),
+                    max_occurs,
+                    occurs,
+                    Usage::new(self.cmd)
+                        .required(&self.required)
+                        .create_usage_with_title(&[]),
+                ));
+            }
+        }
+
+        Ok(())
+    }
+
+    fn validate_arg_num_vals(&self, a: &Arg, ma: &MatchedArg) -> ClapResult<()> {
+        debug!("Validator::validate_arg_num_vals");
+        if let Some(num) = a.num_vals {
+            let total_num = ma.num_vals();
+            debug!("Validator::validate_arg_num_vals: num_vals set...{}", num);
+            #[allow(deprecated)]
+            let should_err = if a.is_multiple_occurrences_set() {
+                total_num % num != 0
+            } else {
+                num != total_num
+            };
+            if should_err {
+                debug!("Validator::validate_arg_num_vals: Sending error WrongNumberOfValues");
+                return Err(Error::wrong_number_of_values(
+                    self.cmd,
+                    a.to_string(),
+                    num,
+                    #[allow(deprecated)]
+                    if a.is_multiple_occurrences_set() {
+                        total_num % num
+                    } else {
+                        total_num
+                    },
+                    Usage::new(self.cmd)
+                        .required(&self.required)
+                        .create_usage_with_title(&[]),
+                ));
+            }
+        }
+        if let Some(num) = a.max_vals {
+            debug!("Validator::validate_arg_num_vals: max_vals set...{}", num);
+            if ma.num_vals() > num {
+                debug!("Validator::validate_arg_num_vals: Sending error TooManyValues");
+                return Err(Error::too_many_values(
+                    self.cmd,
+                    ma.raw_vals_flatten()
+                        .last()
+                        .expect(INTERNAL_ERROR_MSG)
+                        .to_str()
+                        .expect(INVALID_UTF8)
+                        .to_string(),
+                    a.to_string(),
+                    Usage::new(self.cmd)
+                        .required(&self.required)
+                        .create_usage_with_title(&[]),
+                ));
+            }
+        }
+        let min_vals_zero = if let Some(num) = a.min_vals {
+            debug!("Validator::validate_arg_num_vals: min_vals set: {}", num);
+            if ma.num_vals() < num && num != 0 {
+                debug!("Validator::validate_arg_num_vals: Sending error TooFewValues");
+                return Err(Error::too_few_values(
+                    self.cmd,
+                    a.to_string(),
+                    num,
+                    ma.num_vals(),
+                    Usage::new(self.cmd)
+                        .required(&self.required)
+                        .create_usage_with_title(&[]),
+                ));
+            }
+            num == 0
+        } else {
+            false
+        };
+        // Issue 665 (https://github.com/clap-rs/clap/issues/665)
+        // Issue 1105 (https://github.com/clap-rs/clap/issues/1105)
+        if a.is_takes_value_set() && !min_vals_zero && ma.all_val_groups_empty() {
+            return Err(Error::empty_value(
+                self.cmd,
+                &get_possible_values(a)
+                    .iter()
+                    .filter(|pv| !pv.is_hide_set())
+                    .map(PossibleValue::get_name)
+                    .collect::<Vec<_>>(),
+                a.to_string(),
+            ));
+        }
+        Ok(())
+    }
+
+    fn validate_required(
+        &mut self,
+        matcher: &ArgMatcher,
+        conflicts: &mut Conflicts,
+    ) -> ClapResult<()> {
+        debug!("Validator::validate_required: required={:?}", self.required);
+        self.gather_requires(matcher);
+
+        let is_exclusive_present = matcher
+            .arg_ids()
+            .filter(|arg_id| matcher.check_explicit(arg_id, ArgPredicate::IsPresent))
+            .any(|id| {
+                self.cmd
+                    .find(id)
+                    .map(|arg| arg.is_exclusive_set())
+                    .unwrap_or_default()
+            });
+        debug!(
+            "Validator::validate_required: is_exclusive_present={}",
+            is_exclusive_present
+        );
+
+        for arg_or_group in self
+            .required
+            .iter()
+            .filter(|r| !matcher.check_explicit(r, ArgPredicate::IsPresent))
+        {
+            debug!("Validator::validate_required:iter:aog={:?}", arg_or_group);
+            if let Some(arg) = self.cmd.find(arg_or_group) {
+                debug!("Validator::validate_required:iter: This is an arg");
+                if !is_exclusive_present && !self.is_missing_required_ok(arg, matcher, conflicts) {
+                    return self.missing_required_error(matcher, vec![]);
+                }
+            } else if let Some(group) = self.cmd.find_group(arg_or_group) {
+                debug!("Validator::validate_required:iter: This is a group");
+                if !self
+                    .cmd
+                    .unroll_args_in_group(&group.id)
+                    .iter()
+                    .any(|a| matcher.check_explicit(a, ArgPredicate::IsPresent))
+                {
+                    return self.missing_required_error(matcher, vec![]);
+                }
+            }
+        }
+
+        // Validate the conditionally required args
+        for a in self.cmd.get_arguments() {
+            for (other, val) in &a.r_ifs {
+                if matcher.check_explicit(other, ArgPredicate::Equals(std::ffi::OsStr::new(*val)))
+                    && !matcher.check_explicit(&a.id, ArgPredicate::IsPresent)
+                {
+                    return self.missing_required_error(matcher, vec![a.id.clone()]);
+                }
+            }
+
+            let match_all = a.r_ifs_all.iter().all(|(other, val)| {
+                matcher.check_explicit(other, ArgPredicate::Equals(std::ffi::OsStr::new(*val)))
+            });
+            if match_all
+                && !a.r_ifs_all.is_empty()
+                && !matcher.check_explicit(&a.id, ArgPredicate::IsPresent)
+            {
+                return self.missing_required_error(matcher, vec![a.id.clone()]);
+            }
+        }
+
+        self.validate_required_unless(matcher)?;
+
+        Ok(())
+    }
+
+    fn is_missing_required_ok(
+        &self,
+        a: &Arg<'help>,
+        matcher: &ArgMatcher,
+        conflicts: &mut Conflicts,
+    ) -> bool {
+        debug!("Validator::is_missing_required_ok: {}", a.name);
+        let conflicts = conflicts.gather_conflicts(self.cmd, matcher, &a.id);
+        !conflicts.is_empty()
+    }
+
+    fn validate_required_unless(&self, matcher: &ArgMatcher) -> ClapResult<()> {
+        debug!("Validator::validate_required_unless");
+        let failed_args: Vec<_> = self
+            .cmd
+            .get_arguments()
+            .filter(|&a| {
+                (!a.r_unless.is_empty() || !a.r_unless_all.is_empty())
+                    && !matcher.check_explicit(&a.id, ArgPredicate::IsPresent)
+                    && self.fails_arg_required_unless(a, matcher)
+            })
+            .map(|a| a.id.clone())
+            .collect();
+        if failed_args.is_empty() {
+            Ok(())
+        } else {
+            self.missing_required_error(matcher, failed_args)
+        }
+    }
+
+    // Failing a required unless means, the arg's "unless" wasn't present, and neither were they
+    fn fails_arg_required_unless(&self, a: &Arg<'help>, matcher: &ArgMatcher) -> bool {
+        debug!("Validator::fails_arg_required_unless: a={:?}", a.name);
+        let exists = |id| matcher.check_explicit(id, ArgPredicate::IsPresent);
+
+        (a.r_unless_all.is_empty() || !a.r_unless_all.iter().all(exists))
+            && !a.r_unless.iter().any(exists)
+    }
+
+    // `incl`: an arg to include in the error even if not used
+    fn missing_required_error(&self, matcher: &ArgMatcher, incl: Vec<Id>) -> ClapResult<()> {
+        debug!("Validator::missing_required_error; incl={:?}", incl);
+        debug!(
+            "Validator::missing_required_error: reqs={:?}",
+            self.required
+        );
+
+        let usg = Usage::new(self.cmd).required(&self.required);
+
+        let req_args = usg
+            .get_required_usage_from(&incl, Some(matcher), true)
+            .into_iter()
+            .collect::<Vec<_>>();
+
+        debug!(
+            "Validator::missing_required_error: req_args={:#?}",
+            req_args
+        );
+
+        let used: Vec<Id> = matcher
+            .arg_ids()
+            .filter(|arg_id| matcher.check_explicit(arg_id, ArgPredicate::IsPresent))
+            .filter(|n| {
+                // Filter out the args we don't want to specify.
+                self.cmd.find(n).map_or(true, |a| !a.is_hide_set())
+            })
+            .cloned()
+            .chain(incl)
+            .collect();
+
+        Err(Error::missing_required_argument(
+            self.cmd,
+            req_args,
+            usg.create_usage_with_title(&used),
+        ))
+    }
+}
+
+#[derive(Default, Clone, Debug)]
+struct Conflicts {
+    potential: std::collections::HashMap<Id, Vec<Id>>,
+}
+
+impl Conflicts {
+    fn new() -> Self {
+        Self::default()
+    }
+
+    fn gather_conflicts(&mut self, cmd: &Command, matcher: &ArgMatcher, arg_id: &Id) -> Vec<Id> {
+        debug!("Conflicts::gather_conflicts: arg={:?}", arg_id);
+        let mut conflicts = Vec::new();
+        for other_arg_id in matcher
+            .arg_ids()
+            .filter(|arg_id| matcher.check_explicit(arg_id, ArgPredicate::IsPresent))
+        {
+            if arg_id == other_arg_id {
+                continue;
+            }
+
+            if self
+                .gather_direct_conflicts(cmd, arg_id)
+                .contains(other_arg_id)
+            {
+                conflicts.push(other_arg_id.clone());
+            }
+            if self
+                .gather_direct_conflicts(cmd, other_arg_id)
+                .contains(arg_id)
+            {
+                conflicts.push(other_arg_id.clone());
+            }
+        }
+        debug!("Conflicts::gather_conflicts: conflicts={:?}", conflicts);
+        conflicts
+    }
+
+    fn gather_direct_conflicts(&mut self, cmd: &Command, arg_id: &Id) -> &[Id] {
+        self.potential.entry(arg_id.clone()).or_insert_with(|| {
+            let conf = if let Some(arg) = cmd.find(arg_id) {
+                let mut conf = arg.blacklist.clone();
+                for group_id in cmd.groups_for_arg(arg_id) {
+                    let group = cmd.find_group(&group_id).expect(INTERNAL_ERROR_MSG);
+                    conf.extend(group.conflicts.iter().cloned());
+                    if !group.multiple {
+                        for member_id in &group.args {
+                            if member_id != arg_id {
+                                conf.push(member_id.clone());
+                            }
+                        }
+                    }
+                }
+
+                // Overrides are implicitly conflicts
+                conf.extend(arg.overrides.iter().cloned());
+
+                conf
+            } else if let Some(group) = cmd.find_group(arg_id) {
+                group.conflicts.clone()
+            } else {
+                debug_assert!(false, "id={:?} is unknown", arg_id);
+                Vec::new()
+            };
+            debug!(
+                "Conflicts::gather_direct_conflicts id={:?}, conflicts={:?}",
+                arg_id, conf
+            );
+            conf
+        })
+    }
+}
+
+fn get_possible_values<'help>(a: &Arg<'help>) -> Vec<PossibleValue<'help>> {
+    #![allow(deprecated)]
+    if !a.is_takes_value_set() {
+        vec![]
+    } else if let Some(pvs) = a.get_possible_values() {
+        // Check old first in case the user explicitly set possible values and the derive inferred
+        // a `ValueParser` with some.
+        pvs.to_vec()
+    } else {
+        a.get_value_parser()
+            .possible_values()
+            .map(|pvs| pvs.collect())
+            .unwrap_or_default()
+    }
+}
diff --git a/vendor/clap-3.2.20/src/util/color.rs b/vendor/clap-3.2.20/src/util/color.rs
new file mode 100644
index 000000000..15c9901a0
--- /dev/null
+++ b/vendor/clap-3.2.20/src/util/color.rs
@@ -0,0 +1,62 @@
+/// Represents the color preferences for program output
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+pub enum ColorChoice {
+    /// Enables colored output only when the output is going to a terminal or TTY.
+    ///
+    /// **NOTE:** This is the default behavior of `clap`.
+    ///
+    /// # Platform Specific
+    ///
+    /// This setting only applies to Unix, Linux, and macOS (i.e. non-Windows platforms).
+    ///
+    /// # Examples
+    ///
+    #[cfg_attr(not(feature = "color"), doc = " ```ignore")]
+    #[cfg_attr(feature = "color", doc = " ```no_run")]
+    /// # use clap::{Command, ColorChoice};
+    /// Command::new("myprog")
+    ///     .color(ColorChoice::Auto)
+    ///     .get_matches();
+    /// ```
+    Auto,
+
+    /// Enables colored output regardless of whether or not the output is going to a terminal/TTY.
+    ///
+    /// # Platform Specific
+    ///
+    /// This setting only applies to Unix, Linux, and macOS (i.e. non-Windows platforms).
+    ///
+    /// # Examples
+    ///
+    #[cfg_attr(not(feature = "color"), doc = " ```ignore")]
+    #[cfg_attr(feature = "color", doc = " ```no_run")]
+    /// # use clap::{Command, ColorChoice};
+    /// Command::new("myprog")
+    ///     .color(ColorChoice::Always)
+    ///     .get_matches();
+    /// ```
+    Always,
+
+    /// Disables colored output no matter if the output is going to a terminal/TTY, or not.
+    ///
+    /// # Platform Specific
+    ///
+    /// This setting only applies to Unix, Linux, and macOS (i.e. non-Windows platforms)
+    ///
+    /// # Examples
+    ///
+    #[cfg_attr(not(feature = "color"), doc = " ```ignore")]
+    #[cfg_attr(feature = "color", doc = " ```no_run")]
+    /// # use clap::{Command, ColorChoice};
+    /// Command::new("myprog")
+    ///     .color(ColorChoice::Never)
+    ///     .get_matches();
+    /// ```
+    Never,
+}
+
+impl Default for ColorChoice {
+    fn default() -> Self {
+        Self::Auto
+    }
+}
diff --git a/vendor/clap-3.2.20/src/util/fnv.rs b/vendor/clap-3.2.20/src/util/fnv.rs
new file mode 100644
index 000000000..4602300a4
--- /dev/null
+++ b/vendor/clap-3.2.20/src/util/fnv.rs
@@ -0,0 +1,46 @@
+use std::{
+    fmt::Display,
+    hash::{Hash, Hasher},
+};
+
+const MAGIC_INIT: u64 = 0x811C_9DC5;
+
+// TODO: Docs
+pub trait Key: Hash + Display {
+    fn key(&self) -> u64;
+}
+
+impl<T> Key for T
+where
+    T: Hash + Display,
+{
+    fn key(&self) -> u64 {
+        let mut hasher = FnvHasher::new();
+        self.hash(&mut hasher);
+        hasher.finish()
+    }
+}
+
+pub(crate) struct FnvHasher(u64);
+
+impl FnvHasher {
+    pub(crate) fn new() -> Self {
+        FnvHasher(MAGIC_INIT)
+    }
+}
+
+impl Hasher for FnvHasher {
+    fn finish(&self) -> u64 {
+        self.0
+    }
+    fn write(&mut self, bytes: &[u8]) {
+        let FnvHasher(mut hash) = *self;
+
+        for byte in bytes.iter() {
+            hash ^= u64::from(*byte);
+            hash = hash.wrapping_mul(0x0100_0000_01b3);
+        }
+
+        *self = FnvHasher(hash);
+    }
+}
diff --git a/vendor/clap-3.2.20/src/util/graph.rs b/vendor/clap-3.2.20/src/util/graph.rs
new file mode 100644
index 000000000..d646400b0
--- /dev/null
+++ b/vendor/clap-3.2.20/src/util/graph.rs
@@ -0,0 +1,49 @@
+#[derive(Debug)]
+struct Child<T> {
+    id: T,
+    children: Vec<usize>,
+}
+
+impl<T> Child<T> {
+    fn new(id: T) -> Self {
+        Child {
+            id,
+            children: vec![],
+        }
+    }
+}
+
+#[derive(Debug)]
+pub(crate) struct ChildGraph<T>(Vec<Child<T>>);
+
+impl<T> ChildGraph<T>
+where
+    T: Sized + PartialEq + Clone,
+{
+    pub(crate) fn with_capacity(s: usize) -> Self {
+        ChildGraph(Vec::with_capacity(s))
+    }
+
+    pub(crate) fn insert(&mut self, req: T) -> usize {
+        self.0.iter().position(|e| e.id == req).unwrap_or_else(|| {
+            let idx = self.0.len();
+            self.0.push(Child::new(req));
+            idx
+        })
+    }
+
+    pub(crate) fn insert_child(&mut self, parent: usize, child: T) -> usize {
+        let c_idx = self.0.len();
+        self.0.push(Child::new(child));
+        self.0[parent].children.push(c_idx);
+        c_idx
+    }
+
+    pub(crate) fn iter(&self) -> impl Iterator<Item = &T> {
+        self.0.iter().map(|r| &r.id)
+    }
+
+    pub(crate) fn contains(&self, req: &T) -> bool {
+        self.0.iter().any(|r| r.id == *req)
+    }
+}
diff --git a/vendor/clap-3.2.20/src/util/id.rs b/vendor/clap-3.2.20/src/util/id.rs
new file mode 100644
index 000000000..63a7e003e
--- /dev/null
+++ b/vendor/clap-3.2.20/src/util/id.rs
@@ -0,0 +1,92 @@
+use crate::util::fnv::Key;
+
+use std::{
+    fmt::{Debug, Formatter, Result},
+    hash::{Hash, Hasher},
+    ops::Deref,
+};
+
+#[derive(Clone, Eq, Default)]
+#[cfg_attr(not(debug_assertions), repr(transparent))]
+pub(crate) struct Id {
+    #[cfg(debug_assertions)]
+    name: String,
+    id: u64,
+}
+
+macro_rules! precomputed_hashes {
+    ($($fn_name:ident, $const:expr, $name:expr;)*) => {
+        impl Id {
+            $(
+                pub(crate) fn $fn_name() -> Self {
+                    Id {
+                        #[cfg(debug_assertions)]
+                        name: $name.into(),
+                        id: $const,
+                    }
+                }
+            )*
+        }
+    };
+}
+
+// precompute some common values
+precomputed_hashes! {
+    empty_hash,   0x1C9D_3ADB_639F_298E, "";
+    help_hash,    0x5963_6393_CFFB_FE5F, "help";
+    version_hash, 0x30FF_0B7C_4D07_9478, "version";
+}
+
+impl Id {
+    pub(crate) fn from_ref<T: Key>(val: T) -> Self {
+        Id {
+            #[cfg(debug_assertions)]
+            name: val.to_string(),
+            id: val.key(),
+        }
+    }
+}
+
+impl Debug for Id {
+    fn fmt(&self, f: &mut Formatter) -> Result {
+        #[cfg(debug_assertions)]
+        write!(f, "{}", self.name)?;
+        #[cfg(not(debug_assertions))]
+        write!(f, "[hash: {:X}]", self.id)?;
+
+        Ok(())
+    }
+}
+
+impl Deref for Id {
+    type Target = u64;
+
+    fn deref(&self) -> &Self::Target {
+        &self.id
+    }
+}
+
+impl<T: Key> From<T> for Id {
+    fn from(val: T) -> Self {
+        Id {
+            #[cfg(debug_assertions)]
+            name: val.to_string(),
+            id: val.key(),
+        }
+    }
+}
+
+impl Hash for Id {
+    fn hash<H>(&self, state: &mut H)
+    where
+        H: Hasher,
+    {
+        self.id.hash(state)
+    }
+}
+
+impl PartialEq for Id {
+    fn eq(&self, other: &Id) -> bool {
+        self.id == other.id
+    }
+}
diff --git a/vendor/clap-3.2.20/src/util/mod.rs b/vendor/clap-3.2.20/src/util/mod.rs
new file mode 100644
index 000000000..8adc8db17
--- /dev/null
+++ b/vendor/clap-3.2.20/src/util/mod.rs
@@ -0,0 +1,40 @@
+#![allow(clippy::single_component_path_imports)]
+
+mod fnv;
+mod graph;
+mod id;
+mod str_to_bool;
+
+pub use self::fnv::Key;
+
+pub(crate) use self::str_to_bool::str_to_bool;
+pub(crate) use self::str_to_bool::FALSE_LITERALS;
+pub(crate) use self::str_to_bool::TRUE_LITERALS;
+pub(crate) use self::{graph::ChildGraph, id::Id};
+
+pub(crate) mod color;
+
+pub(crate) const SUCCESS_CODE: i32 = 0;
+// While sysexists.h defines EX_USAGE as 64, this doesn't seem to be used much in practice but
+// instead 2 seems to be frequently used.
+// Examples
+// - GNU `ls` returns 2
+// - Python's `argparse` returns 2
+pub(crate) const USAGE_CODE: i32 = 2;
+
+pub(crate) fn safe_exit(code: i32) -> ! {
+    use std::io::Write;
+
+    let _ = std::io::stdout().lock().flush();
+    let _ = std::io::stderr().lock().flush();
+
+    std::process::exit(code)
+}
+
+#[cfg(not(feature = "unicode"))]
+pub(crate) fn eq_ignore_case(left: &str, right: &str) -> bool {
+    left.eq_ignore_ascii_case(right)
+}
+
+#[cfg(feature = "unicode")]
+pub(crate) use unicase::eq as eq_ignore_case;
diff --git a/vendor/clap-3.2.20/src/util/str_to_bool.rs b/vendor/clap-3.2.20/src/util/str_to_bool.rs
new file mode 100644
index 000000000..1fbdc7531
--- /dev/null
+++ b/vendor/clap-3.2.20/src/util/str_to_bool.rs
@@ -0,0 +1,21 @@
+/// True values are `y`, `yes`, `t`, `true`, `on`, and `1`.
+pub(crate) const TRUE_LITERALS: [&str; 6] = ["y", "yes", "t", "true", "on", "1"];
+
+/// False values are `n`, `no`, `f`, `false`, `off`, and `0`.
+pub(crate) const FALSE_LITERALS: [&str; 6] = ["n", "no", "f", "false", "off", "0"];
+
+/// Converts a string literal representation of truth to true or false.
+///
+/// `false` values are `n`, `no`, `f`, `false`, `off`, and `0` (case insensitive).
+///
+/// Any other value will be considered as `true`.
+pub(crate) fn str_to_bool(val: impl AsRef<str>) -> Option<bool> {
+    let pat: &str = &val.as_ref().to_lowercase();
+    if TRUE_LITERALS.contains(&pat) {
+        Some(true)
+    } else if FALSE_LITERALS.contains(&pat) {
+        Some(false)
+    } else {
+        None
+    }
+}