refactor(ast_codegen): flatten code (#4743)

A bit of code style simplification after #4731. Remove unnecessary nesting and rename some vars for consistency.

tasks/ast_codegen/src/generators/derive_clone_in.rs

@@ -52,62 +52,59 @@ impl Generator for DeriveCloneIn {
 
 fn derive_enum(def: &EnumDef) -> TokenStream {
  let ty_ident = def.ident();
- let (alloc, body) = {
- let mut used_alloc = false;
- let matches = def
- .all_variants()
- .map(|var| {
- let ident = var.ident();
- if var.is_unit() {
- quote!(Self :: #ident => #ty_ident :: #ident)
- } else {
- used_alloc = true;
- quote!(Self :: #ident(it) => #ty_ident :: #ident(it.clone_in(alloc)))
- }
- })
- .collect_vec();
- let alloc_ident = if used_alloc { format_ident!("alloc") } else { format_ident!("_") };
- (
- alloc_ident,
- quote! {
- match self {
- #(#matches),*
- }
- },
- )
+
+ let mut used_alloc = false;
+ let matches = def
+ .all_variants()
+ .map(|var| {
+ let ident = var.ident();
+ if var.is_unit() {
+ quote!(Self :: #ident => #ty_ident :: #ident)
+ } else {
+ used_alloc = true;
+ quote!(Self :: #ident(it) => #ty_ident :: #ident(it.clone_in(alloc)))
+ }
+ })
+ .collect_vec();
+
+ let alloc_ident = if used_alloc { format_ident!("alloc") } else { format_ident!("_") };
+ let body = quote! {
+ match self {
+ #(#matches),*
+ }
  };
- impl_clone_in(&ty_ident, def.has_lifetime, &alloc, &body)
+
+ impl_clone_in(&ty_ident, def.has_lifetime, &alloc_ident, &body)
 }
 
 fn derive_struct(def: &StructDef) -> TokenStream {
  let ty_ident = def.ident();
- let (alloc, body) = {
- let (alloc_ident, body) = if def.fields.is_empty() {
- (format_ident!("_"), TokenStream::default())
- } else {
- let fields = def.fields.iter().map(|field| {
- let ident = field.ident();
- quote!(#ident: self.#ident.clone_in(alloc))
- });
- (format_ident!("alloc"), quote!({ #(#fields),* }))
- };
- (alloc_ident, quote!( #ty_ident #body ))
+
+ let (alloc_ident, body) = if def.fields.is_empty() {
+ (format_ident!("_"), quote!(#ty_ident))
+ } else {
+ let fields = def.fields.iter().map(|field| {
+ let ident = field.ident();
+ quote!(#ident: self.#ident.clone_in(alloc))
+ });
+ (format_ident!("alloc"), quote!(#ty_ident { #(#fields),* }))
  };
- impl_clone_in(&ty_ident, def.has_lifetime, &alloc, &body)
+
+ impl_clone_in(&ty_ident, def.has_lifetime, &alloc_ident, &body)
 }
 
 fn impl_clone_in(
  ty_ident: &Ident,
  has_lifetime: bool,
- alloc: &Ident,
+ alloc_ident: &Ident,
  body: &TokenStream,
 ) -> TokenStream {
  if has_lifetime {
  quote! {
  endl!();
  impl <'old_alloc, 'new_alloc> CloneIn<'new_alloc> for #ty_ident<'old_alloc> {
  type Cloned = #ty_ident<'new_alloc>;
- fn clone_in(&self, #alloc: &'new_alloc Allocator) -> Self::Cloned {
+ fn clone_in(&self, #alloc_ident: &'new_alloc Allocator) -> Self::Cloned {
  #body
  }
  }
@@ -117,7 +114,7 @@ fn impl_clone_in(
  endl!();
  impl <'alloc> CloneIn<'alloc> for #ty_ident {
  type Cloned = #ty_ident;
- fn clone_in(&self, #alloc: &'alloc Allocator) -> Self::Cloned {
+ fn clone_in(&self, #alloc_ident: &'alloc Allocator) -> Self::Cloned {
  #body
  }
  }