diff options
Diffstat (limited to 'compiler/rustc_builtin_macros/src/util.rs')
-rw-r--r-- | compiler/rustc_builtin_macros/src/util.rs | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/compiler/rustc_builtin_macros/src/util.rs b/compiler/rustc_builtin_macros/src/util.rs new file mode 100644 index 000000000..527fe50ef --- /dev/null +++ b/compiler/rustc_builtin_macros/src/util.rs @@ -0,0 +1,43 @@ +use rustc_ast::{Attribute, MetaItem}; +use rustc_expand::base::{Annotatable, ExtCtxt}; +use rustc_feature::AttributeTemplate; +use rustc_lint_defs::builtin::DUPLICATE_MACRO_ATTRIBUTES; +use rustc_parse::validate_attr; +use rustc_span::Symbol; + +pub fn check_builtin_macro_attribute(ecx: &ExtCtxt<'_>, meta_item: &MetaItem, name: Symbol) { + // All the built-in macro attributes are "words" at the moment. + let template = AttributeTemplate { word: true, ..Default::default() }; + let attr = ecx.attribute(meta_item.clone()); + validate_attr::check_builtin_attribute(&ecx.sess.parse_sess, &attr, name, template); +} + +/// Emit a warning if the item is annotated with the given attribute. This is used to diagnose when +/// an attribute may have been mistakenly duplicated. +pub fn warn_on_duplicate_attribute(ecx: &ExtCtxt<'_>, item: &Annotatable, name: Symbol) { + let attrs: Option<&[Attribute]> = match item { + Annotatable::Item(item) => Some(&item.attrs), + Annotatable::TraitItem(item) => Some(&item.attrs), + Annotatable::ImplItem(item) => Some(&item.attrs), + Annotatable::ForeignItem(item) => Some(&item.attrs), + Annotatable::Expr(expr) => Some(&expr.attrs), + Annotatable::Arm(arm) => Some(&arm.attrs), + Annotatable::ExprField(field) => Some(&field.attrs), + Annotatable::PatField(field) => Some(&field.attrs), + Annotatable::GenericParam(param) => Some(¶m.attrs), + Annotatable::Param(param) => Some(¶m.attrs), + Annotatable::FieldDef(def) => Some(&def.attrs), + Annotatable::Variant(variant) => Some(&variant.attrs), + _ => None, + }; + if let Some(attrs) = attrs { + if let Some(attr) = ecx.sess.find_by_name(attrs, name) { + ecx.parse_sess().buffer_lint( + DUPLICATE_MACRO_ATTRIBUTES, + attr.span, + ecx.current_expansion.lint_node_id, + "duplicated attribute", + ); + } + } +} |