rustdoc: Fix local reexports of proc macros

Filter out `ProcMacroStub`s to avoid an ICE during cleaning. Also add proc macros to `cache().paths` so it can generate links.

Author: ollie27

src/librustdoc/html/render.rs

@@ -1512,7 +1512,8 @@ impl DocFolder for Cache {
  clean::FunctionItem(..) | clean::ModuleItem(..) |
  clean::ForeignFunctionItem(..) | clean::ForeignStaticItem(..) |
  clean::ConstantItem(..) | clean::StaticItem(..) |
- clean::UnionItem(..) | clean::ForeignTypeItem | clean::MacroItem(..)
+ clean::UnionItem(..) | clean::ForeignTypeItem |
+ clean::MacroItem(..) | clean::ProcMacroItem(..)
  if !self.stripped_mod => {
  // Re-exported items mean that the same id can show up twice
  // in the rustdoc ast that we're looking at. We know,

src/librustdoc/visit_ast.rs

@@ -424,10 +424,11 @@ impl<'a, 'tcx, 'rcx, 'cstore> RustdocVisitor<'a, 'tcx, 'rcx, 'cstore> {
  hir::ItemKind::Use(ref path, kind) => {
  let is_glob = kind == hir::UseKind::Glob;
 
- // Struct and variant constructors always show up alongside their definitions, we've
- // already processed them so just discard these.
+ // Struct and variant constructors and proc macro stubs always show up alongside
+ // their definitions, we've already processed them so just discard these.
  match path.def {
- Def::StructCtor(..) | Def::VariantCtor(..) | Def::SelfCtor(..) => return,
+ Def::StructCtor(..) | Def::VariantCtor(..) | Def::SelfCtor(..) |
+ Def::Macro(_, MacroKind::ProcMacroStub) => return,
  _ => {}
  }
 

src/test/rustdoc/proc-macro.rs

@@ -61,3 +61,16 @@ pub fn some_proc_attr(_attr: TokenStream, item: TokenStream) -> TokenStream {
 pub fn some_derive(_item: TokenStream) -> TokenStream {
  TokenStream::new()
 }
+
+// @has some_macros/foo/index.html
+pub mod foo {
+ // @has - '//code' 'pub use some_proc_macro;'
+ // @has - '//a/@href' '../../some_macros/macro.some_proc_macro.html'
+ pub use some_proc_macro;
+ // @has - '//code' 'pub use some_proc_attr;'
+ // @has - '//a/@href' '../../some_macros/attr.some_proc_attr.html'
+ pub use some_proc_attr;
+ // @has - '//code' 'pub use some_derive;'
+ // @has - '//a/@href' '../../some_macros/derive.SomeDerive.html'
+ pub use some_derive;
+}