rustdoc: Print feature flag and issue link if present in short_stability

Author: m4rw3r

src/librustdoc/html/render.rs

@@ -1709,7 +1709,22 @@ fn short_stability(item: &clean::Item, cx: &Context, show_reason: bool) -> Optio
             };
             format!("Deprecated{}{}", since, Markdown(&reason))
         } else if stab.level == attr::Unstable {
-            format!("Unstable{}", Markdown(&reason))
+            let unstable_extra = if show_reason {
+                match (!stab.feature.is_empty(), &cx.issue_tracker_base_url, stab.issue) {
+                    (true, &Some(ref tracker_url), Some(issue_no)) =>
+                        format!(" (<code>{}</code> <a href=\"{}{}\">#{}</a>)", Escape(&stab.feature),
+                                tracker_url, issue_no, issue_no),
+                    (false, &Some(ref tracker_url), Some(issue_no)) =>
+                        format!(" (<a href=\"{}{}\">#{}</a>)", Escape(&tracker_url), issue_no,
+                                issue_no),
+                    (true, _, _) =>
+                        format!(" (<code>{}</code>)", Escape(&stab.feature)),
+                    _ => String::new(),
+                }
+            } else {
+                String::new()
+            };
+            format!("Unstable{}{}", unstable_extra, Markdown(&reason))
         } else {
             return None
         };

src/librustdoc/html/static/main.css

@@ -123,7 +123,7 @@ code, pre {
     font-family: "Source Code Pro", Menlo, Monaco, Consolas, "DejaVu Sans Mono", Inconsolata, monospace;
     white-space: pre-wrap;
 }
-.docblock code {
+.docblock code, .stability code {
     background-color: #F5F5F5;
     border-radius: 3px;
     padding: 0 0.2em;
@@ -387,11 +387,11 @@ a {
     background: transparent;
 }
 
-.docblock a {
+.docblock a, .stability a {
     color: #4e8bca;
 }
 
-.docblock a:hover {
+.docblock a:hover, .stability a {
     text-decoration: underline;
 }