Add FooBase trait so cold types can implement devirt traits without #[devirt] #40
There are no files selected for viewing
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change | ||||
|---|---|---|---|---|---|---|
|
|
@@ -461,6 +461,118 @@ fn build_delegating_methods( | |||||
| .collect() | ||||||
| } | ||||||
|
|
||||||
| fn build_base_trait_items( | ||||||
| trait_item: &syn::ItemTrait, | ||||||
| ) -> Vec<proc_macro2::TokenStream> { | ||||||
| trait_item | ||||||
| .items | ||||||
| .iter() | ||||||
| .filter_map(|item| { | ||||||
| if let syn::TraitItem::Fn(m) = item { | ||||||
| let attrs = &m.attrs; | ||||||
| let sig = &m.sig; | ||||||
| Some(quote! { #(#attrs)* #sig; }) | ||||||
| } else { | ||||||
| None | ||||||
| } | ||||||
| }) | ||||||
| .collect() | ||||||
| } | ||||||
|
|
||||||
| fn build_base_bridge_items( | ||||||
| trait_item: &syn::ItemTrait, | ||||||
| base_name: &syn::Ident, | ||||||
| ) -> Vec<proc_macro2::TokenStream> { | ||||||
| trait_item | ||||||
| .items | ||||||
| .iter() | ||||||
| .filter_map(|item| match item { | ||||||
| syn::TraitItem::Type(t) => { | ||||||
| let type_name = &t.ident; | ||||||
| Some(quote! { | ||||||
| type #type_name = <Self as #base_name>::#type_name; | ||||||
| }) | ||||||
| } | ||||||
| syn::TraitItem::Fn(m) => { | ||||||
| let method_name = &m.sig.ident; | ||||||
| let spec_name = format_ident!("__spec_{method_name}"); | ||||||
| let mut bridge_sig = m.sig.clone(); | ||||||
| bridge_sig.ident = spec_name; | ||||||
| let arg_names: Vec<_> = m | ||||||
| .sig | ||||||
| .inputs | ||||||
| .iter() | ||||||
| .filter_map(|arg| { | ||||||
| if let syn::FnArg::Typed(pat) = arg | ||||||
| && let syn::Pat::Ident(pi) = &*pat.pat | ||||||
| { | ||||||
| return Some(&pi.ident); | ||||||
| } | ||||||
| None | ||||||
| }) | ||||||
| .collect(); | ||||||
| Some(quote! { | ||||||
| #[inline(always)] | ||||||
| #bridge_sig { | ||||||
| #base_name::#method_name(self, #(#arg_names),*) | ||||||
| } | ||||||
|
Comment on lines
+510
to
+513
There was a problem hiding this comment.
Useful? React with 👍 / 👎. |
||||||
| }) | ||||||
|
Comment on lines
+510
to
+514
There was a problem hiding this comment. The bridge methods generated for the blanket implementation do not preserve attributes from the original trait methods. While |
||||||
| } | ||||||
| _ => None, | ||||||
| }) | ||||||
| .collect() | ||||||
| } | ||||||
|
Comment on lines
+485
to
+519
There was a problem hiding this comment. The current implementation of
Using the existing fn build_base_bridge_items(
trait_item: &syn::ItemTrait,
base_name: &syn::Ident,
trait_ty_generics: &syn::TypeGenerics<'_>,
) -> Vec<proc_macro2::TokenStream> {
trait_item
.items
.iter()
.filter_map(|item| match item {
syn::TraitItem::Type(t) => {
let type_name = &t.ident;
Some(quote! {
type #type_name = <Self as #base_name #trait_ty_generics>::#type_name;
})
}
syn::TraitItem::Fn(m) => {
let method_name = &m.sig.ident;
let spec_name = format_ident!("__spec_{method_name}");
let (mut bridge_sig, arg_names) = rewrite_sig_with_named_args(&m.sig);
bridge_sig.ident = spec_name;
Some(quote! {
#[inline(always)]
#bridge_sig {
<Self as #base_name #trait_ty_generics>::#method_name(self, #(#arg_names),*)
}
})
}
_ => None,
})
.collect()
}
Owner
Author
There was a problem hiding this comment. Rust edition 2024 has been stable for years
Owner
Author
There was a problem hiding this comment. Items 2 and 3 were fixed in 16205cb — Generated by Claude Code |
||||||
|
|
||||||
| #[expect(clippy::too_many_arguments)] | ||||||
| fn build_base_trait_expansion( | ||||||
| trait_item: &syn::ItemTrait, | ||||||
| unsafety: Option<&syn::token::Unsafe>, | ||||||
| has_trait_generics: bool, | ||||||
| base_name: &syn::Ident, | ||||||
| inner_name: &syn::Ident, | ||||||
| trait_generic_params: &Punctuated<syn::GenericParam, Token![,]>, | ||||||
| trait_ty_generics: &syn::TypeGenerics<'_>, | ||||||
| trait_where_clause: Option<&syn::WhereClause>, | ||||||
| inner_supers: &proc_macro2::TokenStream, | ||||||
| ) -> proc_macro2::TokenStream { | ||||||
| let vis = &trait_item.vis; | ||||||
| let base_trait_items = build_base_trait_items(trait_item); | ||||||
| let base_bridge_items = build_base_bridge_items(trait_item, base_name); | ||||||
|
There was a problem hiding this comment. The call to
Suggested change
|
||||||
| let assoc_type_decls = collect_assoc_types(trait_item).decls; | ||||||
| let trait_def_generics = if has_trait_generics { | ||||||
| quote! { <#trait_generic_params> } | ||||||
| } else { | ||||||
| quote! {} | ||||||
| }; | ||||||
| let base_blanket = if has_trait_generics { | ||||||
| quote! { | ||||||
| #unsafety impl< | ||||||
| __DevirtT: #base_name #trait_ty_generics + ?Sized, | ||||||
| #trait_generic_params | ||||||
| > #inner_name #trait_ty_generics for __DevirtT #trait_where_clause { | ||||||
| #(#base_bridge_items)* | ||||||
| } | ||||||
| } | ||||||
| } else { | ||||||
| quote! { | ||||||
| #unsafety impl<__DevirtT: #base_name + ?Sized> | ||||||
| #inner_name for __DevirtT #trait_where_clause | ||||||
| { | ||||||
| #(#base_bridge_items)* | ||||||
| } | ||||||
| } | ||||||
| }; | ||||||
| quote! { | ||||||
| /// Base implementation trait: implement this for cold types | ||||||
| /// without depending on `devirt`. | ||||||
| #vis #unsafety trait #base_name #trait_def_generics | ||||||
| #inner_supers #trait_where_clause | ||||||
| { #(#assoc_type_decls)* #(#base_trait_items)* } | ||||||
|
|
||||||
| #base_blanket | ||||||
| } | ||||||
| } | ||||||
|
|
||||||
| fn emit_trait_expansion( | ||||||
| trait_item: &syn::ItemTrait, | ||||||
| hot_types: &[syn::Type], | ||||||
|
|
@@ -535,12 +647,21 @@ fn emit_trait_expansion( | |||||
| ); | ||||||
| let assoc_type_decls = &assoc_info.decls; | ||||||
|
|
||||||
| let base_name = format_ident!("{name}Base"); | ||||||
|
There was a problem hiding this comment.
The proc-macro expansion unconditionally creates a new public trait named Useful? React with 👍 / 👎. |
||||||
| let base_expansion = build_base_trait_expansion( | ||||||
| trait_item, unsafety.as_ref(), has_trait_generics, &base_name, | ||||||
| &inner_name, trait_generic_params, &trait_ty_generics, | ||||||
| trait_where_clause.as_ref(), &inner_supers, | ||||||
| ); | ||||||
|
|
||||||
| quote! { | ||||||
| #[doc(hidden)] | ||||||
| #vis #unsafety trait #inner_name #trait_def_generics | ||||||
| #inner_supers #trait_where_clause | ||||||
| { #(#assoc_type_decls)* #(#spec_decls)* } | ||||||
|
|
||||||
| #base_expansion | ||||||
|
|
||||||
| #fat_ptr_assertion | ||||||
|
|
||||||
| #vtable_helpers | ||||||
|
|
||||||
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Uh oh!
There was an error while loading. Please reload this page.