chore: Dedup clap derive get fields

clap-rs · May 4, 2023 · 003b453 · 003b453
1 parent 3e6a77a
commit 003b453
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Showing 3 changed files with 22 additions and 42 deletions.
diff --git a/clap_derive/src/derives/args.rs b/clap_derive/src/derives/args.rs
@@ -16,7 +16,7 @@ use proc_macro2::{Ident, Span, TokenStream};
 use quote::{format_ident, quote, quote_spanned};
 use syn::{
     punctuated::Punctuated, spanned::Spanned, token::Comma, Data, DataStruct, DeriveInput, Field,
-    Fields, Generics,
+    Fields, FieldsNamed, Generics,
 };
 
 use crate::item::{Item, Kind, Name};
@@ -32,14 +32,7 @@ pub fn derive_args(input: &DeriveInput) -> Result<TokenStream, syn::Error> {
         }) => {
             let name = Name::Derived(ident.clone());
             let item = Item::from_args_struct(input, name)?;
-            let fields = fields
-                .named
-                .iter()
-                .map(|field| {
-                    let item = Item::from_args_field(field, item.casing(), item.env_casing())?;
-                    Ok((field, item))
-                })
-                .collect::<Result<Vec<_>, syn::Error>>()?;
+            let fields = collect_args_fields(&item, fields)?;
             gen_for_struct(&item, ident, &input.generics, &fields)
         }
         Data::Struct(DataStruct {
@@ -740,3 +733,17 @@ pub fn raw_deprecated() -> TokenStream {
 
     }
 }
+
+pub fn collect_args_fields<'a>(
+    item: &'a Item,
+    fields: &'a FieldsNamed,
+) -> Result<Vec<(&'a Field, Item)>, syn::Error> {
+    fields
+        .named
+        .iter()
+        .map(|field| {
+            let item = Item::from_args_field(field, item.casing(), item.env_casing())?;
+            Ok((field, item))
+        })
+        .collect()
+}
diff --git a/clap_derive/src/derives/parser.rs b/clap_derive/src/derives/parser.rs
@@ -21,6 +21,7 @@ use syn::{
     Generics,
 };
 
+use crate::derives::args::collect_args_fields;
 use crate::derives::{args, into_app, subcommand};
 use crate::item::Item;
 use crate::item::Name;
@@ -36,14 +37,7 @@ pub fn derive_parser(input: &DeriveInput) -> Result<TokenStream, syn::Error> {
         }) => {
             let name = Name::Assigned(quote!(#pkg_name));
             let item = Item::from_args_struct(input, name)?;
-            let fields = fields
-                .named
-                .iter()
-                .map(|field| {
-                    let item = Item::from_args_field(field, item.casing(), item.env_casing())?;
-                    Ok((field, item))
-                })
-                .collect::<Result<Vec<_>, syn::Error>>()?;
+            let fields = collect_args_fields(&item, fields)?;
             gen_for_struct(&item, ident, &input.generics, &fields)
         }
         Data::Struct(DataStruct {

diff --git a/clap_derive/src/derives/subcommand.rs b/clap_derive/src/derives/subcommand.rs
@@ -17,6 +17,7 @@ use quote::{format_ident, quote, quote_spanned};
 use syn::{spanned::Spanned, Data, DeriveInput, FieldsUnnamed, Generics, Variant};
 
 use crate::derives::args;
+use crate::derives::args::collect_args_fields;
 use crate::item::{Item, Kind, Name};
 use crate::utils::{is_simple_ty, subty_if_name};
 
@@ -264,15 +265,7 @@ fn gen_augment(
                 let sub_augment = match variant.fields {
                     Named(ref fields) => {
                         // Defer to `gen_augment` for adding cmd methods
-                        let fields = fields
-                            .named
-                            .iter()
-                            .map(|field| {
-                                let item =
-                                    Item::from_args_field(field, item.casing(), item.env_casing())?;
-                                Ok((field, item))
-                            })
-                            .collect::<Result<Vec<_>, syn::Error>>()?;
+                        let fields = collect_args_fields(item, fields)?;
                         args::gen_augment(&fields, &subcommand_var, item, override_required)?
                     }
                     Unit => {
@@ -484,14 +477,7 @@ fn gen_from_arg_matches(variants: &[(&Variant, Item)]) -> Result<TokenStream, sy
         let variant_name = &variant.ident;
         let constructor_block = match variant.fields {
             Named(ref fields) => {
-                let fields = fields
-                    .named
-                    .iter()
-                    .map(|field| {
-                        let item = Item::from_args_field(field, item.casing(), item.env_casing())?;
-                        Ok((field, item))
-                    })
-                    .collect::<Result<Vec<_>, syn::Error>>()?;
+                let fields = collect_args_fields(item, fields)?;
                 args::gen_constructor(&fields)?
             },
             Unit => quote!(),
@@ -599,14 +585,7 @@ fn gen_update_from_arg_matches(variants: &[(&Variant, Item)]) -> Result<TokenStr
                 let field_names = fields.named.iter().map(|field| {
                     field.ident.as_ref().unwrap()
                 }).collect::<Vec<_>>();
-                let fields = fields
-                    .named
-                    .iter()
-                    .map(|field| {
-                        let item = Item::from_args_field(field, item.casing(), item.env_casing())?;
-                        Ok((field, item))
-                    })
-                    .collect::<Result<Vec<_>, syn::Error>>()?;
+                let fields = collect_args_fields(item, fields)?;
                 let update = args::gen_updater(&fields, false)?;
                 (quote!( { #( #field_names, )* }), quote!( { #update } ))
             }