rustdoc: Show macros in documentation

Any macro tagged with #[macro_export] will be showed in the documentation for
that module. This also documents all the existing macros inside of std::macros.

Closes #3163
cc #5605
Closes #9954

Author: alexcrichton

Diff for: src/librustdoc/clean.rs

@@ -181,6 +181,7 @@ pub enum ItemEnum {
     VariantItem(Variant),
     ForeignFunctionItem(Function),
     ForeignStaticItem(Static),
+    MacroItem(Macro),
 }
 
 #[deriving(Clone, Encodable, Decodable)]
@@ -206,7 +207,8 @@ impl Clean<Item> for doctree::Module {
                        self.fns.clean(), self.foreigns.clean().concat_vec(),
                        self.mods.clean(), self.typedefs.clean(),
                        self.statics.clean(), self.traits.clean(),
-                       self.impls.clean(), self.view_items.clean()].concat_vec()
+                       self.impls.clean(), self.view_items.clean(),
+                       self.macros.clean()].concat_vec()
             })
         }
     }
@@ -1263,3 +1265,23 @@ fn resolve_def(id: ast::NodeId) -> Option<ast::DefId> {
         None => None
     }
 }
+
+#[deriving(Clone, Encodable, Decodable)]
+pub struct Macro {
+    source: ~str,
+}
+
+impl Clean<Item> for doctree::Macro {
+    fn clean(&self) -> Item {
+        Item {
+            name: Some(self.name.clean()),
+            attrs: self.attrs.clean(),
+            source: self.where.clean(),
+            visibility: ast::Public.clean(),
+            id: self.id,
+            inner: MacroItem(Macro {
+                source: self.where.to_src(),
+            }),
+        }
+    }
+}

Diff for: src/librustdoc/doctree.rs

@@ -32,6 +32,7 @@ pub struct Module {
     impls: ~[Impl],
     foreigns: ~[ast::ForeignMod],
     view_items: ~[ast::ViewItem],
+    macros: ~[Macro],
 }
 
 impl Module {
@@ -52,6 +53,7 @@ impl Module {
             impls      : ~[],
             view_items : ~[],
             foreigns   : ~[],
+            macros     : ~[],
         }
     }
 }
@@ -157,6 +159,13 @@ pub struct Impl {
     id: ast::NodeId,
 }
 
+pub struct Macro {
+    name: Ident,
+    id: ast::NodeId,
+    attrs: ~[ast::Attribute],
+    where: Span,
+}
+
 pub fn struct_type_from_def(sd: &ast::StructDef) -> StructType {
     if sd.ctor_id.is_some() {
         // We are in a tuple-struct

Diff for: src/librustdoc/html/render.rs

@@ -798,6 +798,7 @@ fn shortty(item: &clean::Item) -> &'static str {
         clean::VariantItem(..)         => "variant",
         clean::ForeignFunctionItem(..) => "ffi",
         clean::ForeignStaticItem(..)   => "ffs",
+        clean::MacroItem(..)           => "macro",
     }
 }
 
@@ -876,6 +877,7 @@ impl<'a> fmt::Show for Item<'a> {
             clean::StructItem(ref s) => item_struct(fmt.buf, self.item, s),
             clean::EnumItem(ref e) => item_enum(fmt.buf, self.item, e),
             clean::TypedefItem(ref t) => item_typedef(fmt.buf, self.item, t),
+            clean::MacroItem(ref m) => item_macro(fmt.buf, self.item, m),
             _ => Ok(())
         }
     }
@@ -944,6 +946,8 @@ fn item_module(w: &mut Writer, cx: &Context,
             (_, &clean::ViewItemItem(..)) => Greater,
             (&clean::ModuleItem(..), _) => Less,
             (_, &clean::ModuleItem(..)) => Greater,
+            (&clean::MacroItem(..), _) => Less,
+            (_, &clean::MacroItem(..)) => Greater,
             (&clean::StructItem(..), _) => Less,
             (_, &clean::StructItem(..)) => Greater,
             (&clean::EnumItem(..), _) => Less,
@@ -994,6 +998,7 @@ fn item_module(w: &mut Writer, cx: &Context,
                 clean::VariantItem(..)         => "Variants",
                 clean::ForeignFunctionItem(..) => "Foreign Functions",
                 clean::ForeignStaticItem(..)   => "Foreign Statics",
+                clean::MacroItem(..)           => "Macros",
             }));
         }
 
@@ -1616,3 +1621,9 @@ impl<'a> fmt::Show for Source<'a> {
         Ok(())
     }
 }
+
+fn item_macro(w: &mut Writer, it: &clean::Item,
+              t: &clean::Macro) -> fmt::Result {
+    if_ok!(write!(w, "<pre class='macro'>{}</pre>", t.source));
+    document(w, it)
+}

Diff for: src/librustdoc/passes.rs

@@ -150,8 +150,8 @@ impl<'a> fold::DocFolder for Stripper<'a> {
             }
             clean::ImplItem(..) => {}
 
-            // tymethods have no control over privacy
-            clean::TyMethodItem(..) => {}
+            // tymethods/macros have no control over privacy
+            clean::MacroItem(..) | clean::TyMethodItem(..) => {}
         }
 
         let fastreturn = match i.inner {

Diff for: src/librustdoc/visit_ast.rs

@@ -280,7 +280,14 @@ impl<'a> RustdocVisitor<'a> {
             ast::ItemForeignMod(ref fm) => {
                 om.foreigns.push(fm.clone());
             }
-            _ => (),
+            ast::ItemMac(ref _m) => {
+                om.macros.push(Macro {
+                    id: item.id,
+                    attrs: item.attrs.clone(),
+                    name: item.ident,
+                    where: item.span,
+                })
+            }
         }
     }
 }

Diff for: src/libstd/lib.rs

@@ -77,7 +77,7 @@
 #[cfg(test)] pub use ops = realstd::ops;
 #[cfg(test)] pub use cmp = realstd::cmp;
 
-mod macros;
+pub mod macros;
 
 mod rtdeps;