diff options
Diffstat (limited to 'compiler/rustc_macros/src')
| -rw-r--r-- | compiler/rustc_macros/src/diagnostics/utils.rs | 2 | ||||
| -rw-r--r-- | compiler/rustc_macros/src/lib.rs | 13 | ||||
| -rw-r--r-- | compiler/rustc_macros/src/print_attribute.rs | 60 | ||||
| -rw-r--r-- | compiler/rustc_macros/src/visitable.rs | 82 |
4 files changed, 115 insertions, 42 deletions
diff --git a/compiler/rustc_macros/src/diagnostics/utils.rs b/compiler/rustc_macros/src/diagnostics/utils.rs index 060799e981d..c310b99d535 100644 --- a/compiler/rustc_macros/src/diagnostics/utils.rs +++ b/compiler/rustc_macros/src/diagnostics/utils.rs @@ -146,7 +146,7 @@ impl<'ty> FieldInnerTy<'ty> { }; let path = &ty_path.path; - let ty = path.segments.iter().last().unwrap(); + let ty = path.segments.last().unwrap(); let syn::PathArguments::AngleBracketed(bracketed) = &ty.arguments else { panic!("expected bracketed generic arguments"); }; diff --git a/compiler/rustc_macros/src/lib.rs b/compiler/rustc_macros/src/lib.rs index 1006ea3ba10..803b3621c88 100644 --- a/compiler/rustc_macros/src/lib.rs +++ b/compiler/rustc_macros/src/lib.rs @@ -21,6 +21,7 @@ mod symbols; mod try_from; mod type_foldable; mod type_visitable; +mod visitable; // Reads the rust version (e.g. "1.75.0") from the CFG_RELEASE env var and // produces a `RustcVersion` literal containing that version (e.g. @@ -101,6 +102,16 @@ decl_derive!( /// visited (and its type is not required to implement `TypeVisitable`). type_visitable::type_visitable_derive ); +decl_derive!( + [Walkable, attributes(visitable)] => + /// Derives `Walkable` for the annotated `struct` or `enum` (`union` is not supported). + /// + /// Each field of the struct or enum variant will be visited in definition order, using the + /// `Walkable` implementation for its type. However, if a field of a struct or an enum + /// variant is annotated with `#[visitable(ignore)]` then that field will not be + /// visited (and its type is not required to implement `Walkable`). + visitable::visitable_derive +); decl_derive!([Lift, attributes(lift)] => lift::lift_derive); decl_derive!( [Diagnostic, attributes( @@ -176,7 +187,7 @@ decl_derive! { decl_derive! { [PrintAttribute] => /// Derives `PrintAttribute` for `AttributeKind`. - /// This macro is pretty specific to `rustc_attr_data_structures` and likely not that useful in + /// This macro is pretty specific to `rustc_hir::attrs` and likely not that useful in /// other places. It's deriving something close to `Debug` without printing some extraneous /// things like spans. print_attribute::print_attribute diff --git a/compiler/rustc_macros/src/print_attribute.rs b/compiler/rustc_macros/src/print_attribute.rs index 9023520c750..0114e0dfde0 100644 --- a/compiler/rustc_macros/src/print_attribute.rs +++ b/compiler/rustc_macros/src/print_attribute.rs @@ -4,7 +4,7 @@ use syn::spanned::Spanned; use syn::{Data, Fields, Ident}; use synstructure::Structure; -fn print_fields(name: &Ident, fields: &Fields) -> (TokenStream, TokenStream, TokenStream) { +fn print_fields(name: &Ident, fields: &Fields) -> (TokenStream, TokenStream) { let string_name = name.to_string(); let mut disps = vec![quote! {let mut __printed_anything = false;}]; @@ -43,7 +43,6 @@ fn print_fields(name: &Ident, fields: &Fields) -> (TokenStream, TokenStream, Tok #(#disps)* __p.word("}"); }, - quote! { true }, ) } Fields::Unnamed(fields_unnamed) => { @@ -76,10 +75,9 @@ fn print_fields(name: &Ident, fields: &Fields) -> (TokenStream, TokenStream, Tok #(#disps)* __p.pclose(); }, - quote! { true }, ) } - Fields::Unit => (quote! {}, quote! { __p.word(#string_name) }, quote! { true }), + Fields::Unit => (quote! {}, quote! { __p.word(#string_name) }), } } @@ -89,51 +87,33 @@ pub(crate) fn print_attribute(input: Structure<'_>) -> TokenStream { }; // Must be applied to an enum type. - let (code, printed) = match &input.ast().data { + let code = match &input.ast().data { Data::Enum(e) => { - let (arms, printed) = e + let arms = e .variants .iter() .map(|x| { let ident = &x.ident; - let (pat, code, printed) = print_fields(ident, &x.fields); + let (pat, code) = print_fields(ident, &x.fields); - ( - quote! { - Self::#ident #pat => {#code} - }, - quote! { - Self::#ident #pat => {#printed} - }, - ) + quote! { + Self::#ident #pat => {#code} + } }) - .unzip::<_, _, Vec<_>, Vec<_>>(); + .collect::<Vec<_>>(); - ( - quote! { - match self { - #(#arms)* - } - }, - quote! { - match self { - #(#printed)* - } - }, - ) + quote! { + match self { + #(#arms)* + } + } } Data::Struct(s) => { - let (pat, code, printed) = print_fields(&input.ast().ident, &s.fields); - ( - quote! { - let Self #pat = self; - #code - }, - quote! { - let Self #pat = self; - #printed - }, - ) + let (pat, code) = print_fields(&input.ast().ident, &s.fields); + quote! { + let Self #pat = self; + #code + } } Data::Union(u) => { return span_error(u.union_token.span(), "can't derive PrintAttribute on unions"); @@ -144,7 +124,7 @@ pub(crate) fn print_attribute(input: Structure<'_>) -> TokenStream { input.gen_impl(quote! { #[allow(unused)] gen impl PrintAttribute for @Self { - fn should_render(&self) -> bool { #printed } + fn should_render(&self) -> bool { true } fn print_attribute(&self, __p: &mut rustc_ast_pretty::pp::Printer) { #code } } }) diff --git a/compiler/rustc_macros/src/visitable.rs b/compiler/rustc_macros/src/visitable.rs new file mode 100644 index 00000000000..a7a82538eab --- /dev/null +++ b/compiler/rustc_macros/src/visitable.rs @@ -0,0 +1,82 @@ +use quote::quote; +use synstructure::BindingInfo; + +pub(super) fn visitable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream { + if let syn::Data::Union(_) = s.ast().data { + panic!("cannot derive on union") + } + + let has_attr = |bind: &BindingInfo<'_>, name| { + let mut found = false; + bind.ast().attrs.iter().for_each(|attr| { + if !attr.path().is_ident("visitable") { + return; + } + let _ = attr.parse_nested_meta(|nested| { + if nested.path.is_ident(name) { + found = true; + } + Ok(()) + }); + }); + found + }; + + let get_attr = |bind: &BindingInfo<'_>, name: &str| { + let mut content = None; + bind.ast().attrs.iter().for_each(|attr| { + if !attr.path().is_ident("visitable") { + return; + } + let _ = attr.parse_nested_meta(|nested| { + if nested.path.is_ident(name) { + let value = nested.value()?; + let value = value.parse()?; + content = Some(value); + } + Ok(()) + }); + }); + content + }; + + s.add_bounds(synstructure::AddBounds::Generics); + s.bind_with(|_| synstructure::BindStyle::Ref); + let ref_visit = s.each(|bind| { + let extra = get_attr(bind, "extra").unwrap_or(quote! {}); + if has_attr(bind, "ignore") { + quote! {} + } else { + quote! { rustc_ast_ir::try_visit!(crate::visit::Visitable::visit(#bind, __visitor, (#extra))) } + } + }); + + s.bind_with(|_| synstructure::BindStyle::RefMut); + let mut_visit = s.each(|bind| { + let extra = get_attr(bind, "extra").unwrap_or(quote! {}); + if has_attr(bind, "ignore") { + quote! {} + } else { + quote! { crate::mut_visit::MutVisitable::visit_mut(#bind, __visitor, (#extra)) } + } + }); + + s.gen_impl(quote! { + gen impl<'__ast, __V> crate::visit::Walkable<'__ast, __V> for @Self + where __V: crate::visit::Visitor<'__ast>, + { + fn walk_ref(&'__ast self, __visitor: &mut __V) -> __V::Result { + match *self { #ref_visit } + <__V::Result as rustc_ast_ir::visit::VisitorResult>::output() + } + } + + gen impl<__V> crate::mut_visit::MutWalkable<__V> for @Self + where __V: crate::mut_visit::MutVisitor, + { + fn walk_mut(&mut self, __visitor: &mut __V) { + match *self { #mut_visit } + } + } + }) +} |