Rollup merge of #48335 - Manishearth:shortcut-links, r=QuietMisdreavus

Implement implied shortcut links for intra-rustdoc-links

cc https://github.com/rust-lang/rust/issues/43466

Needs https://github.com/google/pulldown-cmark/pull/126

r? @QuietMisdreavus

src/librustdoc/Cargo.toml

@@ -10,5 +10,5 @@ path = "lib.rs"
 doctest = false
 
 [dependencies]
-pulldown-cmark = { version = "0.1.0", default-features = false }
+pulldown-cmark = { version = "0.1.2", default-features = false }
 tempdir = "0.3"

src/librustdoc/clean/mod.rs

@@ -1044,7 +1044,7 @@ fn resolve(cx: &DocContext, path_str: &str, is_val: bool) -> Result<(Def, Option
 
 /// Resolve a string as a macro
 fn macro_resolve(cx: &DocContext, path_str: &str) -> Option<Def> {
-    use syntax::ext::base::MacroKind;
+    use syntax::ext::base::{MacroKind, SyntaxExtension};
     use syntax::ext::hygiene::Mark;
     let segment = ast::PathSegment {
         identifier: ast::Ident::from_str(path_str),
@@ -1061,7 +1061,11 @@ fn macro_resolve(cx: &DocContext, path_str: &str) -> Option<Def> {
     let res = resolver
         .resolve_macro_to_def_inner(mark, &path, MacroKind::Bang, false);
     if let Ok(def) = res {
-        Some(def)
+        if let SyntaxExtension::DeclMacro(..) = *resolver.get_macro(def) {
+            Some(def)
+        } else {
+            None
+        }
     } else if let Some(def) = resolver.all_macros.get(&path_str.into()) {
         Some(*def)
     } else {

src/librustdoc/html/markdown.rs

@@ -591,7 +591,15 @@ impl<'a> fmt::Display for Markdown<'a> {
         opts.insert(OPTION_ENABLE_TABLES);
         opts.insert(OPTION_ENABLE_FOOTNOTES);
 
-        let p = Parser::new_ext(md, opts);
+        let replacer = |_: &str, s: &str| {
+            if let Some(&(_, ref replace)) = links.into_iter().find(|link| &*link.0 == s) {
+                Some((replace.clone(), s.to_owned()))
+            } else {
+                None
+            }
+        };
+
+        let p = Parser::new_with_broken_link_callback(md, opts, Some(&replacer));
 
         let mut s = String::with_capacity(md.len() * 3 / 2);
 
@@ -662,7 +670,16 @@ impl<'a> fmt::Display for MarkdownSummaryLine<'a> {
         // This is actually common enough to special-case
         if md.is_empty() { return Ok(()) }
 
-        let p = Parser::new(md);
+        let replacer = |_: &str, s: &str| {
+            if let Some(&(_, ref replace)) = links.into_iter().find(|link| &*link.0 == s) {
+                Some((replace.clone(), s.to_owned()))
+            } else {
+                None
+            }
+        };
+
+        let p = Parser::new_with_broken_link_callback(md, Options::empty(),
+                                                      Some(&replacer));
 
         let mut s = String::new();
 
@@ -731,18 +748,30 @@ pub fn markdown_links(md: &str) -> Vec<String> {
     opts.insert(OPTION_ENABLE_TABLES);
     opts.insert(OPTION_ENABLE_FOOTNOTES);
 
-    let p = Parser::new_ext(md, opts);
-
-    let iter = Footnotes::new(HeadingLinks::new(p, None));
     let mut links = vec![];
+    let shortcut_links = RefCell::new(vec![]);
 
-    for ev in iter {
-        if let Event::Start(Tag::Link(dest, _)) = ev {
-            debug!("found link: {}", dest);
-            links.push(dest.into_owned());
+    {
+        let push = |_: &str, s: &str| {
+            shortcut_links.borrow_mut().push(s.to_owned());
+            None
+        };
+        let p = Parser::new_with_broken_link_callback(md, opts,
+            Some(&push));
+
+        let iter = Footnotes::new(HeadingLinks::new(p, None));
+
+        for ev in iter {
+            if let Event::Start(Tag::Link(dest, _)) = ev {
+                debug!("found link: {}", dest);
+                links.push(dest.into_owned());
+            }
         }
     }
 
+    let mut shortcut_links = shortcut_links.into_inner();
+    links.extend(shortcut_links.drain(..));
+
     links
 }