Improved rustdoc rendering for unstable features

3 files changed, 35 insertions, 14 deletions

diff --git a/src/librustdoc/html/render.rs b/src/librustdoc/html/render.rs
index 5253c1e9b27..e161f40b729 100644
--- a/src/librustdoc/html/render.rs
+++ b/src/librustdoc/html/render.rs
@@ -1871,8 +1871,10 @@ fn short_stability(item: &clean::Item, cx: &Context, show_reason: bool) -> Vec<S
         };
 
         if stab.level == stability::Unstable {
-            let unstable_extra = if show_reason {
-                match (!stab.feature.is_empty(), &cx.shared.issue_tracker_base_url, stab.issue) {
+            if show_reason {
+                let unstable_extra = match (!stab.feature.is_empty(),
+                                            &cx.shared.issue_tracker_base_url,
+                                            stab.issue) {
                     (true, &Some(ref tracker_url), Some(issue_no)) if issue_no > 0 =>
                         format!(" (<code>{}</code> <a href=\"{}{}\">#{}</a>)",
                                 Escape(&stab.feature), tracker_url, issue_no, issue_no),
@@ -1882,17 +1884,22 @@ fn short_stability(item: &clean::Item, cx: &Context, show_reason: bool) -> Vec<S
                     (true, ..) =>
                         format!(" (<code>{}</code>)", Escape(&stab.feature)),
                     _ => String::new(),
+                };
+                if stab.unstable_reason.is_empty() {
+                    stability.push(format!("<div class='stab unstable'>\
+                                            <span class=microscope>🔬</span> \
+                                            This is a nightly-only experimental API. {}</div>",
+                                   unstable_extra));
+                } else {
+                    let text = format!("<summary><span class=microscope>🔬</span> \
+                                        This is a nightly-only experimental API. {}</summary>{}",
+                                       unstable_extra, MarkdownHtml(&stab.unstable_reason));
+                    stability.push(format!("<div class='stab unstable'><details>{}</details></div>",
+                                   text));
                 }
             } else {
-                String::new()
-            };
-            let unstable_reason = if show_reason && !stab.unstable_reason.is_empty() {
-                format!(": {}", stab.unstable_reason)
-            } else {
-                String::new()
-            };
-            let text = format!("Unstable{}{}", unstable_extra, MarkdownHtml(&unstable_reason));
-            stability.push(format!("<div class='stab unstable'>{}</div>", text))
+                stability.push(format!("<div class='stab unstable'>Experimental</div>"))
+            }
         };
     } else if let Some(depr) = item.deprecation.as_ref() {
         let note = if show_reason && !depr.note.is_empty() {
diff --git a/src/librustdoc/html/static/rustdoc.css b/src/librustdoc/html/static/rustdoc.css
index 0ca4f7ea36f..681d2354056 100644
--- a/src/librustdoc/html/static/rustdoc.css
+++ b/src/librustdoc/html/static/rustdoc.css
@@ -535,6 +535,14 @@ body.blur > :not(#help) {
 	display: inline;
 }
 
+.stab summary {
+	display: list-item;
+}
+
+.stab .microscope {
+	font-size: 1.5em;
+}
+
 .module-item .stab {
 	display: inline;
 	border-width: 0;
diff --git a/src/test/rustdoc/issue-32374.rs b/src/test/rustdoc/issue-32374.rs
index dea73317e5e..b5edf535057 100644
--- a/src/test/rustdoc/issue-32374.rs
+++ b/src/test/rustdoc/issue-32374.rs
@@ -14,14 +14,14 @@
 #![unstable(feature="test", issue = "32374")]
 
 // @has issue_32374/index.html '//*[@class="docblock-short"]' \
-//      '[Deprecated] [Unstable]'
+//      '[Deprecated] [Experimental]'
 
 // @has issue_32374/struct.T.html '//*[@class="stab deprecated"]' \
 //      'Deprecated since 1.0.0: text'
 // @has - '<code>test</code>'
 // @has - '<a href="http://issue_url/32374">#32374</a>'
 // @matches issue_32374/struct.T.html '//*[@class="stab unstable"]' \
-//      'Unstable \(test #32374\)$'
+//      '🔬 This is a nightly-only experimental API.  \(test #32374\)$'
 #[rustc_deprecated(since = "1.0.0", reason = "text")]
 #[unstable(feature = "test", issue = "32374")]
 pub struct T;
@@ -29,7 +29,13 @@ pub struct T;
 // @has issue_32374/struct.U.html '//*[@class="stab deprecated"]' \
 //      'Deprecated since 1.0.0: deprecated'
 // @has issue_32374/struct.U.html '//*[@class="stab unstable"]' \
-//      'Unstable (test #32374): unstable'
+//      '🔬 This is a nightly-only experimental API.  (test #32374)'
+// @has issue_32374/struct.U.html '//details' \
+//      '🔬 This is a nightly-only experimental API.  (test #32374)'
+// @has issue_32374/struct.U.html '//summary' \
+//      '🔬 This is a nightly-only experimental API.  (test #32374)'
+// @has issue_32374/struct.U.html '//details/p' \
+//      'unstable'
 #[rustc_deprecated(since = "1.0.0", reason = "deprecated")]
 #[unstable(feature = "test", issue = "32374", reason = "unstable")]
 pub struct U;