diff options
Diffstat (limited to 'compiler/rustc_macros/src/type_visitable.rs')
| -rw-r--r-- | compiler/rustc_macros/src/type_visitable.rs | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/compiler/rustc_macros/src/type_visitable.rs b/compiler/rustc_macros/src/type_visitable.rs index f6f4c4779..dcd505a10 100644 --- a/compiler/rustc_macros/src/type_visitable.rs +++ b/compiler/rustc_macros/src/type_visitable.rs @@ -1,5 +1,5 @@ use quote::quote; -use syn::{parse_quote, Attribute, Meta, NestedMeta}; +use syn::parse_quote; pub fn type_visitable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream { if let syn::Data::Union(_) = s.ast().data { @@ -8,19 +8,21 @@ pub fn type_visitable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2: // ignore fields with #[type_visitable(ignore)] s.filter(|bi| { - !bi.ast() - .attrs - .iter() - .map(Attribute::parse_meta) - .filter_map(Result::ok) - .flat_map(|attr| match attr { - Meta::List(list) if list.path.is_ident("type_visitable") => list.nested, - _ => Default::default(), - }) - .any(|nested| match nested { - NestedMeta::Meta(Meta::Path(path)) => path.is_ident("ignore"), - _ => false, - }) + let mut ignored = false; + + bi.ast().attrs.iter().for_each(|attr| { + if !attr.path().is_ident("type_visitable") { + return; + } + let _ = attr.parse_nested_meta(|nested| { + if nested.path.is_ident("ignore") { + ignored = true; + } + Ok(()) + }); + }); + + !ignored }); if !s.ast().generics.lifetimes().any(|lt| lt.lifetime.ident == "tcx") { |