//! conflicts between multiple such attributes attached to the same
//! item.
-use rustc_ast::{ast, AttrStyle, Attribute, Lit, LitKind, MetaItemKind, NestedMetaItem};
+use rustc_ast::tokenstream::DelimSpan;
+use rustc_ast::{ast, AttrStyle, Attribute, Lit, LitKind, MacArgs, MetaItemKind, NestedMetaItem};
use rustc_data_structures::fx::FxHashMap;
use rustc_errors::{pluralize, struct_span_err, Applicability, MultiSpan};
use rustc_feature::{AttributeDuplicates, AttributeType, BuiltinAttribute, BUILTIN_ATTRIBUTE_MAP};
}
}
+ /// Checks `#[doc(hidden)]` attributes. Returns `true` if valid.
+ fn check_doc_hidden(
+ &self,
+ attr: &Attribute,
+ meta_index: usize,
+ meta: &NestedMetaItem,
+ hir_id: HirId,
+ target: Target,
+ ) -> bool {
+ if let Target::AssocConst
+ | Target::AssocTy
+ | Target::Method(MethodKind::Trait { body: true }) = target
+ {
+ let parent_hir_id = self.tcx.hir().get_parent_item(hir_id);
+ let containing_item = self.tcx.hir().expect_item(parent_hir_id);
+
+ if Target::from_item(containing_item) == Target::Impl {
+ let meta_items = attr.meta_item_list().unwrap();
+
+ let (span, replacement_span) = if meta_items.len() == 1 {
+ (attr.span, attr.span)
+ } else {
+ let meta_span = meta.span();
+ (
+ meta_span,
+ meta_span.until(match meta_items.get(meta_index + 1) {
+ Some(next_item) => next_item.span(),
+ None => match attr.get_normal_item().args {
+ MacArgs::Delimited(DelimSpan { close, .. }, ..) => close,
+ _ => unreachable!(),
+ },
+ }),
+ )
+ };
+
+ // FIXME: #[doc(hidden)] was previously erroneously allowed on trait impl items,
+ // so for backward compatibility only emit a warning and do not mark it as invalid.
+ self.tcx.struct_span_lint_hir(UNUSED_ATTRIBUTES, hir_id, span, |lint| {
+ lint.build("`#[doc(hidden)]` is ignored on trait impl items")
+ .warn(
+ "this was previously accepted by the compiler but is \
+ being phased out; it will become a hard error in \
+ a future release!",
+ )
+ .note(
+ "whether the impl item is `doc(hidden)` or not \
+ entirely depends on the corresponding trait item",
+ )
+ .span_suggestion(
+ replacement_span,
+ "remove this attribute",
+ String::new(),
+ Applicability::MachineApplicable,
+ )
+ .emit();
+ });
+ }
+ }
+
+ true
+ }
+
/// Checks that an attribute is *not* used at the crate level. Returns `true` if valid.
fn check_attr_not_crate_level(
&self,
let mut is_valid = true;
if let Some(mi) = attr.meta() && let Some(list) = mi.meta_item_list() {
- for meta in list {
+ for (meta_index, meta) in list.into_iter().enumerate() {
if let Some(i_meta) = meta.meta_item() {
match i_meta.name_or_empty() {
sym::alias
is_valid = false;
}
+ sym::hidden if !self.check_doc_hidden(attr,
+ meta_index,
+ meta,
+ hir_id,
+ target,
+ ) => {
+ is_valid = false;
+ }
+
// no_default_passes: deprecated
// passes: deprecated
// plugins: removed, but rustdoc warns about it itself