From 97e73eea84e8302ae08f88645538ee27485770d6 Mon Sep 17 00:00:00 2001
From: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Date: Sat, 18 Feb 2023 14:56:31 +0400
Subject: [PATCH] doc links: Filter away autolinks in both rustc and rustdoc

---
 compiler/rustc_resolve/src/rustdoc.rs | 21 +++++++++++++++++++--
 src/librustdoc/html/markdown.rs       | 24 ++++++++----------------
 2 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/compiler/rustc_resolve/src/rustdoc.rs b/compiler/rustc_resolve/src/rustdoc.rs
index be49fbfaa29..0c4b4bc3f62 100644
--- a/compiler/rustc_resolve/src/rustdoc.rs
+++ b/compiler/rustc_resolve/src/rustdoc.rs
@@ -1,4 +1,4 @@
-use pulldown_cmark::{BrokenLink, Event, Options, Parser, Tag};
+use pulldown_cmark::{BrokenLink, Event, LinkType, Options, Parser, Tag};
 use rustc_ast as ast;
 use rustc_ast::util::comments::beautify_doc_string;
 use rustc_data_structures::fx::FxHashMap;
@@ -347,6 +347,21 @@ fn preprocess_link(link: &str) -> String {
     strip_generics_from_path(link).unwrap_or_else(|_| link.to_string())
 }
 
+/// Keep inline and reference links `[]`,
+/// but skip autolinks `<>` which we never consider to be intra-doc links.
+pub fn may_be_doc_link(link_type: LinkType) -> bool {
+    match link_type {
+        LinkType::Inline
+        | LinkType::Reference
+        | LinkType::ReferenceUnknown
+        | LinkType::Collapsed
+        | LinkType::CollapsedUnknown
+        | LinkType::Shortcut
+        | LinkType::ShortcutUnknown => true,
+        LinkType::Autolink | LinkType::Email => false,
+    }
+}
+
 /// Simplified version of `preprocessed_markdown_links` from rustdoc.
 /// Must return at least the same links as it, but may add some more links on top of that.
 pub(crate) fn attrs_to_preprocessed_links(attrs: &[ast::Attribute]) -> Vec<String> {
@@ -359,7 +374,9 @@ pub(crate) fn attrs_to_preprocessed_links(attrs: &[ast::Attribute]) -> Vec<Strin
         Some(&mut |link: BrokenLink<'_>| Some((link.reference, "".into()))),
     )
     .filter_map(|event| match event {
-        Event::Start(Tag::Link(_, dest, _)) => Some(preprocess_link(&dest)),
+        Event::Start(Tag::Link(link_type, dest, _)) if may_be_doc_link(link_type) => {
+            Some(preprocess_link(&dest))
+        }
         _ => None,
     })
     .collect()
diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index a34628991b2..9ef0b501c08 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -29,6 +29,7 @@
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::TyCtxt;
 pub(crate) use rustc_resolve::rustdoc::main_body_opts;
+use rustc_resolve::rustdoc::may_be_doc_link;
 use rustc_span::edition::Edition;
 use rustc_span::{Span, Symbol};
 
@@ -1269,22 +1270,13 @@ pub(crate) fn markdown_links<R>(
     )
     .into_offset_iter()
     .filter_map(|(event, span)| match event {
-        Event::Start(Tag::Link(
-            // `<>` links cannot be intra-doc links so we skip them.
-            kind @ (LinkType::Inline
-            | LinkType::Reference
-            | LinkType::ReferenceUnknown
-            | LinkType::Collapsed
-            | LinkType::CollapsedUnknown
-            | LinkType::Shortcut
-            | LinkType::ShortcutUnknown),
-            dest,
-            _,
-        )) => preprocess_link(MarkdownLink {
-            kind,
-            range: span_for_link(&dest, span),
-            link: dest.into_string(),
-        }),
+        Event::Start(Tag::Link(link_type, dest, _)) if may_be_doc_link(link_type) => {
+            preprocess_link(MarkdownLink {
+                kind: link_type,
+                range: span_for_link(&dest, span),
+                link: dest.into_string(),
+            })
+        }
         _ => None,
     })
     .collect()