Rollup merge of #36045 - ollie27:rustdoc_titles3, r=steveklabnik

rustdoc: Add missing item types to page titles

Most pages include the item type in the title such as "Struct std::vec::Vec". However it is missing from the pages for foreign functions, type definitions, macros, statics and constants. This adds them so for example, instead of a title of "std::u32::MAX" it is "Constant std::u32::MAX" to match the others.

[before](https://doc.rust-lang.org/nightly/std/u32/constant.MAX.html) [after](https://ollie27.github.io/rust_doc_test/std/u32/constant.MAX.html)
[before](https://doc.rust-lang.org/nightly/std/io/type.Result.html) [after](https://ollie27.github.io/rust_doc_test/std/io/type.Result.html)

Previous discussions: #34345, #35003

src/librustdoc/html/render.rs

@@ -1560,13 +1560,22 @@ impl<'a> fmt::Display for Item<'a> {
                 } else {
                     write!(fmt, "Module ")?;
                 },
-            clean::FunctionItem(..) => write!(fmt, "Function ")?,
+            clean::FunctionItem(..) | clean::ForeignFunctionItem(..) =>
+                write!(fmt, "Function ")?,
             clean::TraitItem(..) => write!(fmt, "Trait ")?,
             clean::StructItem(..) => write!(fmt, "Struct ")?,
             clean::UnionItem(..) => write!(fmt, "Union ")?,
             clean::EnumItem(..) => write!(fmt, "Enum ")?,
+            clean::TypedefItem(..) => write!(fmt, "Type Definition ")?,
+            clean::MacroItem(..) => write!(fmt, "Macro ")?,
             clean::PrimitiveItem(..) => write!(fmt, "Primitive Type ")?,
-            _ => {}
+            clean::StaticItem(..) | clean::ForeignStaticItem(..) =>
+                write!(fmt, "Static ")?,
+            clean::ConstantItem(..) => write!(fmt, "Constant ")?,
+            _ => {
+                // We don't generate pages for any other type.
+                unreachable!();
+            }
         }
         if !self.item.is_primitive() {
             let cur = &self.cx.current;
@@ -1628,7 +1637,10 @@ impl<'a> fmt::Display for Item<'a> {
             clean::StaticItem(ref i) | clean::ForeignStaticItem(ref i) =>
                 item_static(fmt, self.cx, self.item, i),
             clean::ConstantItem(ref c) => item_constant(fmt, self.cx, self.item, c),
-            _ => Ok(())
+            _ => {
+                // We don't generate pages for any other type.
+                unreachable!();
+            }
         }
     }
 }

src/test/rustdoc/titles.rs

@@ -0,0 +1,59 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![crate_name = "foo"]
+
+// @matches 'foo/index.html' '//h1' 'Crate foo'
+
+// @matches 'foo/foo_mod/index.html' '//h1' 'Module foo::foo_mod'
+pub mod foo_mod {
+    pub struct __Thing {}
+}
+
+extern {
+    // @matches 'foo/fn.foo_ffn.html' '//h1' 'Function foo::foo_ffn'
+    pub fn foo_ffn();
+}
+
+// @matches 'foo/fn.foo_fn.html' '//h1' 'Function foo::foo_fn'
+pub fn foo_fn() {}
+
+// @matches 'foo/trait.FooTrait.html' '//h1' 'Trait foo::FooTrait'
+pub trait FooTrait {}
+
+// @matches 'foo/struct.FooStruct.html' '//h1' 'Struct foo::FooStruct'
+pub struct FooStruct;
+
+// @matches 'foo/enum.FooEnum.html' '//h1' 'Enum foo::FooEnum'
+pub enum FooEnum {}
+
+// @matches 'foo/type.FooType.html' '//h1' 'Type Definition foo::FooType'
+pub type FooType = FooStruct;
+
+// @matches 'foo/macro.foo_macro.html' '//h1' 'Macro foo::foo_macro'
+#[macro_export]
+macro_rules! foo_macro {
+    () => ();
+}
+
+// @matches 'foo/primitive.bool.html' '//h1' 'Primitive Type bool'
+#[doc(primitive = "bool")]
+mod bool {}
+
+// @matches 'foo/static.FOO_STATIC.html' '//h1' 'Static foo::FOO_STATIC'
+pub static FOO_STATIC: FooStruct = FooStruct;
+
+extern {
+    // @matches 'foo/static.FOO_FSTATIC.html' '//h1' 'Static foo::FOO_FSTATIC'
+    pub static FOO_FSTATIC: FooStruct;
+}
+
+// @matches 'foo/constant.FOO_CONSTANT.html' '//h1' 'Constant foo::FOO_CONSTANT'
+pub const FOO_CONSTANT: FooStruct = FooStruct;