diff options
Diffstat (limited to 'third_party/rust/clap_derive/src/derives/subcommand.rs')
| -rw-r--r-- | third_party/rust/clap_derive/src/derives/subcommand.rs | 666 |
1 files changed, 666 insertions, 0 deletions
diff --git a/third_party/rust/clap_derive/src/derives/subcommand.rs b/third_party/rust/clap_derive/src/derives/subcommand.rs new file mode 100644 index 0000000000..7d12347985 --- /dev/null +++ b/third_party/rust/clap_derive/src/derives/subcommand.rs @@ -0,0 +1,666 @@ +// Copyright 2018 Guillaume Pinot (@TeXitoi) <texitoi@texitoi.eu>, +// Kevin Knapp (@kbknapp) <kbknapp@gmail.com>, and +// Ana Hobden (@hoverbear) <operator@hoverbear.org> +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. +// +// This work was derived from Structopt (https://github.com/TeXitoi/structopt) +// commit#ea76fa1b1b273e65e3b0b1046643715b49bec51f which is licensed under the +// MIT/Apache 2.0 license. +use crate::{ + attrs::{Attrs, Kind, Name, DEFAULT_CASING, DEFAULT_ENV_CASING}, + derives::args, + dummies, + utils::{is_simple_ty, subty_if_name, Sp}, +}; + +use proc_macro2::{Ident, Span, TokenStream}; +use proc_macro_error::{abort, abort_call_site}; +use quote::{format_ident, quote, quote_spanned}; +use syn::{ + punctuated::Punctuated, spanned::Spanned, Attribute, Data, DataEnum, DeriveInput, + FieldsUnnamed, Generics, Token, Variant, +}; + +pub fn derive_subcommand(input: &DeriveInput) -> TokenStream { + let ident = &input.ident; + + dummies::subcommand(ident); + + match input.data { + Data::Enum(ref e) => gen_for_enum(ident, &input.generics, &input.attrs, e), + _ => abort_call_site!("`#[derive(Subcommand)]` only supports enums"), + } +} + +pub fn gen_for_enum( + enum_name: &Ident, + generics: &Generics, + attrs: &[Attribute], + e: &DataEnum, +) -> TokenStream { + let from_arg_matches = gen_from_arg_matches_for_enum(enum_name, generics, attrs, e); + + let attrs = Attrs::from_struct( + Span::call_site(), + attrs, + Name::Derived(enum_name.clone()), + Sp::call_site(DEFAULT_CASING), + Sp::call_site(DEFAULT_ENV_CASING), + ); + let augmentation = gen_augment(&e.variants, &attrs, false); + let augmentation_update = gen_augment(&e.variants, &attrs, true); + let has_subcommand = gen_has_subcommand(&e.variants, &attrs); + + let (impl_generics, ty_generics, where_clause) = generics.split_for_impl(); + + quote! { + #from_arg_matches + + #[allow(dead_code, unreachable_code, unused_variables, unused_braces)] + #[allow( + clippy::style, + clippy::complexity, + clippy::pedantic, + clippy::restriction, + clippy::perf, + clippy::deprecated, + clippy::nursery, + clippy::cargo, + clippy::suspicious_else_formatting, + )] + #[deny(clippy::correctness)] + impl #impl_generics clap::Subcommand for #enum_name #ty_generics #where_clause { + fn augment_subcommands <'b>(__clap_app: clap::Command<'b>) -> clap::Command<'b> { + #augmentation + } + fn augment_subcommands_for_update <'b>(__clap_app: clap::Command<'b>) -> clap::Command<'b> { + #augmentation_update + } + fn has_subcommand(__clap_name: &str) -> bool { + #has_subcommand + } + } + } +} + +fn gen_from_arg_matches_for_enum( + name: &Ident, + generics: &Generics, + attrs: &[Attribute], + e: &DataEnum, +) -> TokenStream { + let attrs = Attrs::from_struct( + Span::call_site(), + attrs, + Name::Derived(name.clone()), + Sp::call_site(DEFAULT_CASING), + Sp::call_site(DEFAULT_ENV_CASING), + ); + + let from_arg_matches = gen_from_arg_matches(name, &e.variants, &attrs); + let update_from_arg_matches = gen_update_from_arg_matches(name, &e.variants, &attrs); + + let (impl_generics, ty_generics, where_clause) = generics.split_for_impl(); + + quote! { + #[allow(dead_code, unreachable_code, unused_variables, unused_braces)] + #[allow( + clippy::style, + clippy::complexity, + clippy::pedantic, + clippy::restriction, + clippy::perf, + clippy::deprecated, + clippy::nursery, + clippy::cargo, + clippy::suspicious_else_formatting, + )] + #[deny(clippy::correctness)] + impl #impl_generics clap::FromArgMatches for #name #ty_generics #where_clause { + #from_arg_matches + #update_from_arg_matches + } + } +} + +fn gen_augment( + variants: &Punctuated<Variant, Token![,]>, + parent_attribute: &Attrs, + override_required: bool, +) -> TokenStream { + use syn::Fields::*; + + let app_var = Ident::new("__clap_app", Span::call_site()); + + let subcommands: Vec<_> = variants + .iter() + .filter_map(|variant| { + let attrs = Attrs::from_variant( + variant, + parent_attribute.casing(), + parent_attribute.env_casing(), + ); + let kind = attrs.kind(); + + match &*kind { + Kind::Skip(_) => None, + + Kind::ExternalSubcommand => { + let ty = match variant.fields { + Unnamed(ref fields) if fields.unnamed.len() == 1 => &fields.unnamed[0].ty, + + _ => abort!( + variant, + "The enum variant marked with `external_subcommand` must be \ + a single-typed tuple, and the type must be either `Vec<String>` \ + or `Vec<OsString>`." + ), + }; + let subcommand = match subty_if_name(ty, "Vec") { + Some(subty) => { + if is_simple_ty(subty, "OsString") { + quote_spanned! { kind.span()=> + let #app_var = #app_var.allow_external_subcommands(true).allow_invalid_utf8_for_external_subcommands(true); + } + } else { + quote_spanned! { kind.span()=> + let #app_var = #app_var.allow_external_subcommands(true); + } + } + } + + None => abort!( + ty.span(), + "The type must be `Vec<_>` \ + to be used with `external_subcommand`." + ), + }; + Some(subcommand) + } + + Kind::Flatten => match variant.fields { + Unnamed(FieldsUnnamed { ref unnamed, .. }) if unnamed.len() == 1 => { + let ty = &unnamed[0]; + let old_heading_var = format_ident!("__clap_old_heading"); + let next_help_heading = attrs.next_help_heading(); + let next_display_order = attrs.next_display_order(); + let subcommand = if override_required { + quote! { + let #old_heading_var = #app_var.get_next_help_heading(); + let #app_var = #app_var #next_help_heading #next_display_order; + let #app_var = <#ty as clap::Subcommand>::augment_subcommands_for_update(#app_var); + let #app_var = #app_var.next_help_heading(#old_heading_var); + } + } else { + quote! { + let #old_heading_var = #app_var.get_next_help_heading(); + let #app_var = #app_var #next_help_heading #next_display_order; + let #app_var = <#ty as clap::Subcommand>::augment_subcommands(#app_var); + let #app_var = #app_var.next_help_heading(#old_heading_var); + } + }; + Some(subcommand) + } + _ => abort!( + variant, + "`flatten` is usable only with single-typed tuple variants" + ), + }, + + Kind::Subcommand(_) => { + let subcommand_var = Ident::new("__clap_subcommand", Span::call_site()); + let arg_block = match variant.fields { + Named(_) => { + abort!(variant, "non single-typed tuple enums are not supported") + } + Unit => quote!( #subcommand_var ), + Unnamed(FieldsUnnamed { ref unnamed, .. }) if unnamed.len() == 1 => { + let ty = &unnamed[0]; + if override_required { + quote_spanned! { ty.span()=> + { + <#ty as clap::Subcommand>::augment_subcommands_for_update(#subcommand_var) + } + } + } else { + quote_spanned! { ty.span()=> + { + <#ty as clap::Subcommand>::augment_subcommands(#subcommand_var) + } + } + } + } + Unnamed(..) => { + abort!(variant, "non single-typed tuple enums are not supported") + } + }; + + let name = attrs.cased_name(); + let initial_app_methods = attrs.initial_top_level_methods(); + let final_from_attrs = attrs.final_top_level_methods(); + let subcommand = quote! { + let #app_var = #app_var.subcommand({ + let #subcommand_var = clap::Command::new(#name); + let #subcommand_var = #subcommand_var #initial_app_methods; + let #subcommand_var = #arg_block; + #[allow(deprecated)] + let #subcommand_var = #subcommand_var.setting(clap::AppSettings::SubcommandRequiredElseHelp); + #subcommand_var #final_from_attrs + }); + }; + Some(subcommand) + } + + _ => { + let subcommand_var = Ident::new("__clap_subcommand", Span::call_site()); + let sub_augment = match variant.fields { + Named(ref fields) => { + // Defer to `gen_augment` for adding cmd methods + args::gen_augment(&fields.named, &subcommand_var, &attrs, override_required) + } + Unit => { + let arg_block = quote!( #subcommand_var ); + let initial_app_methods = attrs.initial_top_level_methods(); + let final_from_attrs = attrs.final_top_level_methods(); + quote! { + let #subcommand_var = #subcommand_var #initial_app_methods; + let #subcommand_var = #arg_block; + #subcommand_var #final_from_attrs + } + }, + Unnamed(FieldsUnnamed { ref unnamed, .. }) if unnamed.len() == 1 => { + let ty = &unnamed[0]; + let arg_block = if override_required { + quote_spanned! { ty.span()=> + { + <#ty as clap::Args>::augment_args_for_update(#subcommand_var) + } + } + } else { + quote_spanned! { ty.span()=> + { + <#ty as clap::Args>::augment_args(#subcommand_var) + } + } + }; + let initial_app_methods = attrs.initial_top_level_methods(); + let final_from_attrs = attrs.final_top_level_methods(); + quote! { + let #subcommand_var = #subcommand_var #initial_app_methods; + let #subcommand_var = #arg_block; + #subcommand_var #final_from_attrs + } + } + Unnamed(..) => { + abort!(variant, "non single-typed tuple enums are not supported") + } + }; + + let name = attrs.cased_name(); + let subcommand = quote! { + let #app_var = #app_var.subcommand({ + let #subcommand_var = clap::Command::new(#name); + #sub_augment + }); + }; + Some(subcommand) + } + } + }) + .collect(); + + let initial_app_methods = parent_attribute.initial_top_level_methods(); + let final_app_methods = parent_attribute.final_top_level_methods(); + quote! { + let #app_var = #app_var #initial_app_methods; + #( #subcommands )*; + #app_var #final_app_methods + } +} + +fn gen_has_subcommand( + variants: &Punctuated<Variant, Token![,]>, + parent_attribute: &Attrs, +) -> TokenStream { + use syn::Fields::*; + + let mut ext_subcmd = false; + + let (flatten_variants, variants): (Vec<_>, Vec<_>) = variants + .iter() + .filter_map(|variant| { + let attrs = Attrs::from_variant( + variant, + parent_attribute.casing(), + parent_attribute.env_casing(), + ); + + if let Kind::ExternalSubcommand = &*attrs.kind() { + ext_subcmd = true; + None + } else { + Some((variant, attrs)) + } + }) + .partition(|(_, attrs)| { + let kind = attrs.kind(); + matches!(&*kind, Kind::Flatten) + }); + + let subcommands = variants.iter().map(|(_variant, attrs)| { + let sub_name = attrs.cased_name(); + quote! { + if #sub_name == __clap_name { + return true + } + } + }); + let child_subcommands = flatten_variants + .iter() + .map(|(variant, _attrs)| match variant.fields { + Unnamed(ref fields) if fields.unnamed.len() == 1 => { + let ty = &fields.unnamed[0]; + quote! { + if <#ty as clap::Subcommand>::has_subcommand(__clap_name) { + return true; + } + } + } + _ => abort!( + variant, + "`flatten` is usable only with single-typed tuple variants" + ), + }); + + if ext_subcmd { + quote! { true } + } else { + quote! { + #( #subcommands )* + + #( #child_subcommands )else* + + false + } + } +} + +fn gen_from_arg_matches( + name: &Ident, + variants: &Punctuated<Variant, Token![,]>, + parent_attribute: &Attrs, +) -> TokenStream { + use syn::Fields::*; + + let mut ext_subcmd = None; + + let subcommand_name_var = format_ident!("__clap_name"); + let sub_arg_matches_var = format_ident!("__clap_sub_arg_matches"); + let (flatten_variants, variants): (Vec<_>, Vec<_>) = variants + .iter() + .filter_map(|variant| { + let attrs = Attrs::from_variant( + variant, + parent_attribute.casing(), + parent_attribute.env_casing(), + ); + + if let Kind::ExternalSubcommand = &*attrs.kind() { + if ext_subcmd.is_some() { + abort!( + attrs.kind().span(), + "Only one variant can be marked with `external_subcommand`, \ + this is the second" + ); + } + + let ty = match variant.fields { + Unnamed(ref fields) if fields.unnamed.len() == 1 => &fields.unnamed[0].ty, + + _ => abort!( + variant, + "The enum variant marked with `external_subcommand` must be \ + a single-typed tuple, and the type must be either `Vec<String>` \ + or `Vec<OsString>`." + ), + }; + + let (span, str_ty, values_of) = match subty_if_name(ty, "Vec") { + Some(subty) => { + if is_simple_ty(subty, "String") { + ( + subty.span(), + quote!(::std::string::String), + quote!(values_of), + ) + } else if is_simple_ty(subty, "OsString") { + ( + subty.span(), + quote!(::std::ffi::OsString), + quote!(values_of_os), + ) + } else { + abort!( + ty.span(), + "The type must be either `Vec<String>` or `Vec<OsString>` \ + to be used with `external_subcommand`." + ); + } + } + + None => abort!( + ty.span(), + "The type must be either `Vec<String>` or `Vec<OsString>` \ + to be used with `external_subcommand`." + ), + }; + + ext_subcmd = Some((span, &variant.ident, str_ty, values_of)); + None + } else { + Some((variant, attrs)) + } + }) + .partition(|(_, attrs)| { + let kind = attrs.kind(); + matches!(&*kind, Kind::Flatten) + }); + + let subcommands = variants.iter().map(|(variant, attrs)| { + let sub_name = attrs.cased_name(); + let variant_name = &variant.ident; + let constructor_block = match variant.fields { + Named(ref fields) => args::gen_constructor(&fields.named, attrs), + Unit => quote!(), + Unnamed(ref fields) if fields.unnamed.len() == 1 => { + let ty = &fields.unnamed[0]; + quote!( ( <#ty as clap::FromArgMatches>::from_arg_matches(__clap_arg_matches)? ) ) + } + Unnamed(..) => abort_call_site!("{}: tuple enums are not supported", variant.ident), + }; + + if cfg!(feature = "unstable-v4") { + quote! { + if #sub_name == #subcommand_name_var && !#sub_arg_matches_var.is_present("") { + return ::std::result::Result::Ok(#name :: #variant_name #constructor_block) + } + } + } else { + quote! { + if #sub_name == #subcommand_name_var { + return ::std::result::Result::Ok(#name :: #variant_name #constructor_block) + } + } + } + }); + let child_subcommands = flatten_variants.iter().map(|(variant, _attrs)| { + let variant_name = &variant.ident; + match variant.fields { + Unnamed(ref fields) if fields.unnamed.len() == 1 => { + let ty = &fields.unnamed[0]; + quote! { + if <#ty as clap::Subcommand>::has_subcommand(__clap_name) { + let __clap_res = <#ty as clap::FromArgMatches>::from_arg_matches(__clap_arg_matches)?; + return ::std::result::Result::Ok(#name :: #variant_name (__clap_res)); + } + } + } + _ => abort!( + variant, + "`flatten` is usable only with single-typed tuple variants" + ), + } + }); + + let wildcard = match ext_subcmd { + Some((span, var_name, str_ty, values_of)) => quote_spanned! { span=> + ::std::result::Result::Ok(#name::#var_name( + ::std::iter::once(#str_ty::from(#subcommand_name_var)) + .chain( + #sub_arg_matches_var.#values_of("").into_iter().flatten().map(#str_ty::from) + ) + .collect::<::std::vec::Vec<_>>() + )) + }, + + None => quote! { + ::std::result::Result::Err(clap::Error::raw(clap::ErrorKind::UnrecognizedSubcommand, format!("The subcommand '{}' wasn't recognized", #subcommand_name_var))) + }, + }; + + quote! { + fn from_arg_matches(__clap_arg_matches: &clap::ArgMatches) -> ::std::result::Result<Self, clap::Error> { + if let Some((#subcommand_name_var, #sub_arg_matches_var)) = __clap_arg_matches.subcommand() { + { + let __clap_arg_matches = #sub_arg_matches_var; + #( #subcommands )* + } + + #( #child_subcommands )else* + + #wildcard + } else { + ::std::result::Result::Err(clap::Error::raw(clap::ErrorKind::MissingSubcommand, "A subcommand is required but one was not provided.")) + } + } + } +} + +fn gen_update_from_arg_matches( + name: &Ident, + variants: &Punctuated<Variant, Token![,]>, + parent_attribute: &Attrs, +) -> TokenStream { + use syn::Fields::*; + + let (flatten, variants): (Vec<_>, Vec<_>) = variants + .iter() + .filter_map(|variant| { + let attrs = Attrs::from_variant( + variant, + parent_attribute.casing(), + parent_attribute.env_casing(), + ); + + match &*attrs.kind() { + // Fallback to `from_arg_matches` + Kind::ExternalSubcommand => None, + _ => Some((variant, attrs)), + } + }) + .partition(|(_, attrs)| { + let kind = attrs.kind(); + matches!(&*kind, Kind::Flatten) + }); + + let subcommands = variants.iter().map(|(variant, attrs)| { + let sub_name = attrs.cased_name(); + let variant_name = &variant.ident; + let (pattern, updater) = match variant.fields { + Named(ref fields) => { + let (fields, update): (Vec<_>, Vec<_>) = fields + .named + .iter() + .map(|field| { + let attrs = Attrs::from_field( + field, + parent_attribute.casing(), + parent_attribute.env_casing(), + ); + let field_name = field.ident.as_ref().unwrap(); + ( + quote!( ref mut #field_name ), + args::gen_updater(&fields.named, &attrs, false), + ) + }) + .unzip(); + (quote!( { #( #fields, )* }), quote!( { #( #update )* } )) + } + Unit => (quote!(), quote!({})), + Unnamed(ref fields) => { + if fields.unnamed.len() == 1 { + ( + quote!((ref mut __clap_arg)), + quote!(clap::FromArgMatches::update_from_arg_matches( + __clap_arg, + __clap_sub_arg_matches + )?), + ) + } else { + abort_call_site!("{}: tuple enums are not supported", variant.ident) + } + } + }; + + quote! { + #name :: #variant_name #pattern if #sub_name == __clap_name => { + let __clap_arg_matches = __clap_sub_arg_matches; + #updater + } + } + }); + + let child_subcommands = flatten.iter().map(|(variant, _attrs)| { + let variant_name = &variant.ident; + match variant.fields { + Unnamed(ref fields) if fields.unnamed.len() == 1 => { + let ty = &fields.unnamed[0]; + quote! { + if <#ty as clap::Subcommand>::has_subcommand(__clap_name) { + if let #name :: #variant_name (child) = s { + <#ty as clap::FromArgMatches>::update_from_arg_matches(child, __clap_arg_matches)?; + return ::std::result::Result::Ok(()); + } + } + } + } + _ => abort!( + variant, + "`flatten` is usable only with single-typed tuple variants" + ), + } + }); + + quote! { + fn update_from_arg_matches<'b>( + &mut self, + __clap_arg_matches: &clap::ArgMatches, + ) -> ::std::result::Result<(), clap::Error> { + if let Some((__clap_name, __clap_sub_arg_matches)) = __clap_arg_matches.subcommand() { + match self { + #( #subcommands ),* + s => { + #( #child_subcommands )* + *s = <Self as clap::FromArgMatches>::from_arg_matches(__clap_arg_matches)?; + } + } + } + ::std::result::Result::Ok(()) + } + } +} |