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-rw-r--r--vendor/xflags/src/lib.rs172
-rw-r--r--vendor/xflags/src/rt.rs14
2 files changed, 137 insertions, 49 deletions
diff --git a/vendor/xflags/src/lib.rs b/vendor/xflags/src/lib.rs
index ae347f511..0eda9dec4 100644
--- a/vendor/xflags/src/lib.rs
+++ b/vendor/xflags/src/lib.rs
@@ -1,12 +1,65 @@
-//! This crates provides a procedural macro for parsing command line arguments.
+//! `xflags` provides a procedural macro for parsing command line arguments.
//!
//! It is intended for use in development tools, so it emphasizes fast compile
//! times and convenience at the expense of features.
//!
-//! If you need something more fancy, consider using
-//! [`clap`](https://docs.rs/clap/2.33.3/clap/) instead.
+//! Rough decision tree for picking an argument parsing library:
//!
-//! ## Example
+//! * if you need all of the features and don't care about minimalism, use
+//! [clap](https://github.com/clap-rs/clap)
+//! * if you want to be maximally minimal, need only basic features (eg, no help
+//! generation), and want to be pedantically correct, use
+//! [lexopt](https://github.com/blyxxyz/lexopt)
+//! * if you want to get things done fast (eg, you want auto help, but not at
+//! the cost of waiting for syn to compile), consider this crate.
+//!
+//! The secret sauce of xflags is that it is the opposite of a derive macro.
+//! Rather than generating a command line grammar from a Rust struct, `xflags`
+//! generates Rust structs based on input grammar. The grammar definition is
+//! both shorter and simpler to write, and is lighter on compile times.
+//!
+//! Here's a complete example of `parse_or_exit!` macro which parses arguments
+//! into an "anonymous" struct:
+//!
+//! ```no_run
+//! use std::path::PathBuf;
+//!
+//! fn main() {
+//! let flags = xflags::parse_or_exit! {
+//! /// Remove directories and their contents recursively.
+//! optional -r,--recursive
+//! /// File or directory to remove
+//! required path: PathBuf
+//! };
+//!
+//! println!(
+//! "removing {}{}",
+//! flags.path.display(),
+//! if flags.recursive { "recursively" } else { "" },
+//! )
+//! }
+//! ```
+//!
+//! The above program, when run with `--help` argument, generates the following
+//! help:
+//!
+//! ```text
+//! ARGS:
+//! <path>
+//! File or directory to remove
+//!
+//! OPTIONS:
+//! -r, --recursive
+//! Remove directories and their contents recursively.
+//!
+//! -h, --help
+//! Prints help information.
+//! ```
+//!
+//! For larger programs, you'd typically want to use `xflags!` macro, which
+//! generates _named_ structs for you. Unlike a typical macro, `xflags` writes
+//! generated code into the source file, to make it easy to understand the rust
+//! types at a glance.
//!
//! ```
//! mod flags {
@@ -15,9 +68,8 @@
//! xflags::xflags! {
//! src "./examples/basic.rs"
//!
-//! cmd my-command
+//! cmd my-command {
//! required path: PathBuf
-//! {
//! optional -v, --verbose
//! }
//! }
@@ -28,17 +80,16 @@
//! #[derive(Debug)]
//! pub struct MyCommand {
//! pub path: PathBuf,
-//!
//! pub verbose: bool,
//! }
//!
//! impl MyCommand {
-//! pub const HELP: &'static str = Self::HELP_;
-//!
+//! pub fn from_env_or_exit() -> Self {
+//! Self::from_env_or_exit_()
+//! }
//! pub fn from_env() -> xflags::Result<Self> {
//! Self::from_env_()
//! }
-//!
//! pub fn from_vec(args: Vec<std::ffi::OsString>) -> xflags::Result<Self> {
//! Self::from_vec_(args)
//! }
@@ -52,15 +103,15 @@
//! }
//! ```
//!
-//! To make the macro less opaque, `xflag` can generate `struct` describing the
-//! CLI in-place. To disable this behavior, omit the `src` attribute.
+//! If you'd rather use a typical proc-macro which generates hidden code, just
+//! omit the src attribute.
//!
//! xflags correctly handles non-utf8 arguments.
//!
//! ## Syntax Reference
//!
-//! The **cmd** keyword introduces a command that accepts positional arguments
-//! and switches.
+//! The `xflags!` macro uses **cmd** keyword to introduce a command or
+//! subcommand that accepts positional arguments and switches.
//!
//! ```
//! xflags::xflags! {
@@ -75,9 +126,9 @@
//! ```
//! xflags::xflags! {
//! cmd switches {
-//! optional -h, --help
-//! repeated --verbose
+//! optional -q,--quiet
//! required --pass-me
+//! repeated --verbose
//! }
//! }
//! ```
@@ -98,20 +149,21 @@
//! }
//! ```
//!
-//! Positional arguments are specified before the opening curly brace:
+//! Arguments without `--` in then are are positional.
//!
//! ```
//! use std::{path::PathBuf, ffi::OsString};
//!
//! xflags::xflags! {
-//! cmd positional-arguments
+//! cmd positional-arguments {
//! required program: PathBuf
//! repeated args: OsString
-//! { }
+//! }
//! }
//! ```
//!
-//! Nesting **cmd** is allowed:
+//! Nesting **cmd** is allowed. `xflag` automatically generates boilerplate
+//! enums for subcommands:
//!
//! ```ignore
//! xflags::xflags! {
@@ -148,12 +200,12 @@
//! }
//!
//! impl App {
-//! pub const HELP: &'static str = Self::HELP_;
-//!
+//! pub fn from_env_or_exit() -> Self {
+//! Self::from_env_or_exit_()
+//! }
//! pub fn from_env() -> xflags::Result<Self> {
//! Self::from_env_()
//! }
-//!
//! pub fn from_vec(args: Vec<std::ffi::OsString>) -> xflags::Result<Self> {
//! Self::from_vec_(args)
//! }
@@ -161,6 +213,9 @@
//! // generated end
//! ```
//!
+//! Switches are always "inherited". Both `app -v foo` and `app foo -v` produce
+//! the same result.
+//!
//! To make subcommand name optional use the **default** keyword to mark a
//! subcommand to select if no subcommand name is passed. The name of the
//! default subcommand affects only the name of the generated Rust struct, it
@@ -176,8 +231,8 @@
//! }
//! ```
//!
-//! Commands, arguments, and switches can documented. Doc comments become a part
-//! of generated help:
+//! Commands, arguments, and switches can be documented. Doc comments become a
+//! part of generated help:
//!
//! ```
//! mod flags {
@@ -185,14 +240,11 @@
//!
//! xflags::xflags! {
//! /// Run basic system diagnostics.
-//! cmd healthck
+//! cmd healthck {
//! /// Optional configuration file.
//! optional config: PathBuf
-//! {
//! /// Verbosity level, can be repeated multiple times.
//! repeated -v, --verbose
-//! /// Print the help message.
-//! optional -h, --help
//! }
//! }
//! }
@@ -200,24 +252,18 @@
//! fn main() {
//! match flags::Healthck::from_env() {
//! Ok(flags) => {
-//! if flags.help {
-//! println!("{}", flags::Healthck::HELP);
-//! return;
-//! }
//! run_checks(flags.config, flags.verbose);
//! }
-//! Err(err) => {
-//! eprintln!("{}", err);
-//! }
+//! Err(err) => err.exit()
//! }
//! }
//!
//! # fn run_checks(_config: Option<std::path::PathBuf>, _verbosity: u32) {}
//! ```
//!
-//! The **src** keyword controlls how the code generation works. If it is
-//! absent, `xflags` acts as a typical procedure macro, which generates a bunch
-//! of structs and impls.
+//! The **src** keyword controls how the code generation works. If it is absent,
+//! `xflags` acts as a typical procedure macro, which generates a bunch of
+//! structs and impls.
//!
//! If the **src** keyword is present, it should specify the path to the file
//! with `xflags!` invocation. The path should be relative to the directory with
@@ -226,7 +272,7 @@
//! directly to the specified file.
//!
//! By convention, `xflag!` macro should be invoked from the `flags` submodule.
-//! The `flags::` preffix should be used to refer to command names. Additional
+//! The `flags::` prefix should be used to refer to command names. Additional
//! validation logic can go to the `flags` module:
//!
//! ```
@@ -250,21 +296,43 @@
//! }
//! }
//! ```
+//!
+//! The `parse_or_exit!` macro is a syntactic sure for `xflags!`, which
+//! immediately parses the argument, exiting the process if needed.
+//! `parse_or_exit` only supports single top-level command and doesn't need the
+//! `cmd` keyword.
+//!
+//! ## Limitations
+//!
+//! `xflags` follows
+//! [Fuchsia](https://fuchsia.dev/fuchsia-src/development/api/cli#command_line_arguments)
+//! conventions for command line arguments. GNU conventions such as grouping
+//! short-flags (`-xyz`) or gluing short flag and a value `(-fVAL)` are not
+//! supported.
+//!
+//! `xflags` requires the command line interface to be fully static. It's
+//! impossible to include additional flags at runtime.
+//!
+//! Implementation is not fully robust, there might be some residual bugs in
+//! edge cases.
use std::fmt;
/// Generates a parser for command line arguments from a DSL.
///
/// See the module-level for detailed syntax specification.
-pub use xflags_macros::xflags;
+pub use xflags_macros::{parse_or_exit, xflags};
pub type Result<T, E = Error> = std::result::Result<T, E>;
-/// This type represents an error that can occur during command line argument
-/// parsing.
+/// An error occurred when parssing command line arguments.
+///
+/// Either the command line was syntactically invalid, or `--help` was
+/// explicitly requested.
#[derive(Debug)]
pub struct Error {
msg: String,
+ help: bool,
}
impl fmt::Display for Error {
@@ -280,7 +348,23 @@ impl Error {
///
/// Use this to report custom validation errors.
pub fn new(message: impl Into<String>) -> Error {
- Error { msg: message.into() }
+ Error { msg: message.into(), help: false }
+ }
+
+ /// Error that carries `--help` message.
+ pub fn is_help(&self) -> bool {
+ self.help
+ }
+
+ /// Prints the error and exists the process.
+ pub fn exit(self) -> ! {
+ if self.is_help() {
+ println!("{self}");
+ std::process::exit(0)
+ } else {
+ eprintln!("{self}");
+ std::process::exit(2)
+ }
}
}
diff --git a/vendor/xflags/src/rt.rs b/vendor/xflags/src/rt.rs
index 3c33196af..988e6cc23 100644
--- a/vendor/xflags/src/rt.rs
+++ b/vendor/xflags/src/rt.rs
@@ -4,7 +4,7 @@ use crate::{Error, Result};
macro_rules! format_err {
($($tt:tt)*) => {
- Error { msg: format!($($tt)*) }
+ Error { msg: format!($($tt)*), help: false }
};
}
@@ -94,6 +94,14 @@ impl Parser {
format_err!("unexpected argument: {:?}", arg)
}
+ pub fn subcommand_required(&self) -> Error {
+ format_err!("subcommand is required")
+ }
+
+ pub fn help(&self, help: &'static str) -> Error {
+ Error { msg: help.to_string(), help: true }
+ }
+
pub fn optional<T>(&self, flag: &str, mut vals: Vec<T>) -> Result<Option<T>> {
if vals.len() > 1 {
bail!("flag specified more than once: `{}`", flag)
@@ -107,8 +115,4 @@ impl Parser {
}
vals.pop().ok_or_else(|| format_err!("flag is required: `{}`", flag))
}
-
- pub fn subcommand<T>(&self, cmd: Option<T>) -> Result<T> {
- cmd.ok_or_else(|| format_err!("subcommand is required"))
- }
}