Rustdoc accessibility: use real headers for doc items

Part of #87059

Partially reverts #84703

Heavily modified for beta backport needs.

Author: bors

src/librustdoc/html/render/mod.rs

@@ -1214,7 +1214,7 @@ fn notable_traits_decl(decl: &clean::FnDecl, cx: &Context<'_>) -> String {
                     if out.is_empty() {
                         write!(
                             &mut out,
-                            "<h3 class=\"notable\">Notable traits for {}</h3>\
+                            "<div class=\"notable\">Notable traits for {}</div>\
                              <code class=\"content\">",
                             impl_.for_.print(cx)
                         );
@@ -1370,15 +1370,15 @@ fn render_impl(
                         "<div id=\"{}\" class=\"{}{} has-srclink\">",
                         id, item_type, in_trait_class,
                     );
-                    w.write_str("<code>");
+                    w.write_str("<h4 class=\"code-header\">");
                     render_assoc_item(
                         w,
                         item,
                         link.anchor(source_id.as_ref().unwrap_or(&id)),
                         ItemType::Impl,
                         cx,
                     );
-                    w.write_str("</code>");
+                    w.write_str("</h4>");
                     render_stability_since_raw(
                         w,
                         item.stable_since(tcx).as_deref(),
@@ -1396,9 +1396,10 @@ fn render_impl(
                 let id = cx.derive_id(source_id.clone());
                 write!(
                     w,
-                    "<div id=\"{}\" class=\"{}{} has-srclink\"><code>",
+                    "<div id=\"{}\" class=\"{}{} has-srclink\">",
                     id, item_type, in_trait_class
                 );
+                w.write_str("<h4 class=\"code-header\">");
                 assoc_type(
                     w,
                     item,
@@ -1408,7 +1409,7 @@ fn render_impl(
                     "",
                     cx,
                 );
-                w.write_str("</code>");
+                w.write_str("</h4>");
                 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
                 w.write_str("</div>");
             }
@@ -1417,9 +1418,10 @@ fn render_impl(
                 let id = cx.derive_id(source_id.clone());
                 write!(
                     w,
-                    "<div id=\"{}\" class=\"{}{} has-srclink\"><code>",
+                    "<div id=\"{}\" class=\"{}{} has-srclink\">",
                     id, item_type, in_trait_class
                 );
+                w.write_str("<h4 class=\"code-header\">");
                 assoc_const(
                     w,
                     item,
@@ -1429,7 +1431,7 @@ fn render_impl(
                     "",
                     cx,
                 );
-                w.write_str("</code>");
+                w.write_str("</h4>");
                 render_stability_since_raw(
                     w,
                     item.stable_since(tcx).as_deref(),
@@ -1444,7 +1446,8 @@ fn render_impl(
             clean::AssocTypeItem(ref bounds, ref default) => {
                 let source_id = format!("{}.{}", item_type, name);
                 let id = cx.derive_id(source_id.clone());
-                write!(w, "<div id=\"{}\" class=\"{}{}\"><code>", id, item_type, in_trait_class,);
+                write!(w, "<div id=\"{}\" class=\"{}{}\">", id, item_type, in_trait_class,);
+                w.write_str("<h4 class=\"code-header\">");
                 assoc_type(
                     w,
                     item,
@@ -1454,7 +1457,7 @@ fn render_impl(
                     "",
                     cx,
                 );
-                w.write_str("</code>");
+                w.write_str("</h4>");
                 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
                 w.write_str("</div>");
             }
@@ -1638,12 +1641,8 @@ fn render_impl_summary(
         format!(" data-aliases=\"{}\"", aliases.join(","))
     };
     if let Some(use_absolute) = use_absolute {
-        write!(
-            w,
-            "<div id=\"{}\" class=\"impl has-srclink\"{}>\
-                     <code class=\"in-band\">",
-            id, aliases
-        );
+        write!(w, "<div id=\"{}\" class=\"impl has-srclink\"{}>", id, aliases);
+        write!(w, "<h3 class=\"code-header in-band\">");
         write!(w, "{}", i.inner_impl().print(use_absolute, cx));
         if show_def_docs {
             for it in &i.inner_impl().items {
@@ -1654,12 +1653,12 @@ fn render_impl_summary(
                 }
             }
         }
-        w.write_str("</code>");
+        w.write_str("</h3>");
     } else {
         write!(
             w,
             "<div id=\"{}\" class=\"impl has-srclink\"{}>\
-                     <code class=\"in-band\">{}</code>",
+                     <h3 class=\"code-header in-band\">{}</h3>",
             id,
             aliases,
             i.inner_impl().print(false, cx)

src/librustdoc/html/render/print_item.rs

@@ -585,9 +585,10 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
         if toggled {
             write!(w, "<details class=\"rustdoc-toggle\" open><summary>");
         }
-        write!(w, "<div id=\"{}\" class=\"method has-srclink\"><code>", id);
+        write!(w, "<div id=\"{}\" class=\"method has-srclink\">", id);
+        write!(w, "<h4 class=\"code-header\">");
         render_assoc_item(w, m, AssocItemLink::Anchor(Some(&id)), ItemType::Impl, cx);
-        w.write_str("</code>");
+        w.write_str("</h4>");
         render_stability_since(w, m, t, cx.tcx());
         write_srclink(cx, m, w);
         w.write_str("</div>");

src/librustdoc/html/static/main.js

@@ -703,8 +703,10 @@ function hideThemeButtonState() {
                     }
                 }
 
-                var code = document.createElement("code");
+                var code = document.createElement("h3");
                 code.innerHTML = struct.text;
+                addClass(code, "code-header");
+                addClass(code, "in-band");
 
                 onEachLazy(code.getElementsByTagName("a"), function(elem) {
                     var href = elem.getAttribute("href");

src/librustdoc/html/static/rustdoc.css

@@ -134,12 +134,25 @@ h1.fqn {
 h1.fqn > .in-band > a:hover {
 	text-decoration: underline;
 }
-h2, h3, h4 {
+#main > h2, #main > h3, #main > h4 {
 	border-bottom: 1px solid;
 }
-.impl, .method,
-.type:not(.container-rustdoc), .associatedconstant,
-.associatedtype {
+h3.code-header, h4.code-header {
+	font-size: 1em;
+	font-weight: 600;
+	border: none;
+	padding: 0;
+	margin: 0;
+}
+.impl,
+.impl-items .method,
+.methods .method,
+.impl-items .type,
+.methods .type,
+.impl-items .associatedconstant,
+.methods .associatedconstant,
+.impl-items .associatedtype,
+.methods .associatedtype {
 	flex-basis: 100%;
 	font-weight: 600;
 	margin-top: 16px;
@@ -190,7 +203,34 @@ summary {
 	outline: none;
 }
 
-code, pre, a.test-arrow {
+/* Fix some style changes due to normalize.css 8 */
+
+td,
+th {
+	padding: 0;
+}
+
+table {
+	border-collapse: collapse;
+}
+
+button,
+input,
+optgroup,
+select,
+textarea {
+	color: inherit;
+	font: inherit;
+	margin: 0;
+}
+
+/* end tweaks for normalize.css 8 */
+
+details:not(.rustdoc-toggle) summary {
+	margin-bottom: .6em;
+}
+
+code, pre, a.test-arrow, .code-header {
 	font-family: "Source Code Pro", monospace;
 }
 .docblock code, .docblock-short code {
@@ -474,9 +514,10 @@ nav.sub {
 	font-weight: normal;
 }
 
-.method > code, .trait-impl > code, .invisible > code {
+.method > .code-header, .trait-impl > .code-header, .invisible > .code-header {
 	max-width: calc(100% - 41px);
 	display: block;
+	flex-grow: 1;
 }
 
 .invisible {
@@ -490,7 +531,7 @@ nav.sub {
 	padding: 0px;
 }
 
-.in-band > code {
+.in-band > code, .in-band > .code-header {
 	display: inline-block;
 }
 
@@ -585,7 +626,7 @@ nav.sub {
 .content .item-info {
 	position: relative;
 	margin-left: 33px;
-	margin-top: -13px;
+	margin-top: -6px;
 }
 
 .sub-variant > div > .item-info {
@@ -596,7 +637,7 @@ nav.sub {
 	content: '⬑';
 	font-size: 25px;
 	position: absolute;
-	top: -6px;
+	top: 0px;
 	left: -19px;
 }
 
@@ -690,7 +731,7 @@ a {
 }
 
 .invisible > .srclink,
-.method > code + .srclink {
+.method > .code-header + .srclink {
 	position: absolute;
 	top: 0;
 	right: 0;
@@ -912,7 +953,7 @@ body.blur > :not(#help) {
 .impl-items .since, .impl .since, .methods .since {
 	flex-grow: 0;
 	padding-left: 12px;
-	padding-right: 2px;
+	padding-right: 6px;
 	position: initial;
 }
 
@@ -1045,8 +1086,7 @@ a.test-arrow:hover{
 	display: block;
 }
 
-
-:target > code {
+:target > code, :target > .code-header {
 	opacity: 1;
 }
 

src/librustdoc/html/static/themes/ayu.css

@@ -133,7 +133,6 @@ pre, .rustdoc.source .example-wrap {
 	color: #708090;
 	background-color: rgba(255, 236, 164, 0.06);
 	padding-right: 4px;
-	border-right: 1px solid #ffb44c;
 }
 
 .docblock h1, .docblock h2, .docblock h3, .docblock h4, .docblock h5 {
@@ -334,7 +333,7 @@ a.test-arrow:hover {
 	color: #999;
 }
 
-:target > code, :target > .in-band {
+:target, :target > * {
 	background: rgba(255, 236, 164, 0.06);
 	border-right: 3px solid rgba(255, 180, 76, 0.85);
 }

src/librustdoc/html/static/themes/dark.css

@@ -282,9 +282,8 @@ a.test-arrow:hover{
 	color: #999;
 }
 
-:target > code, :target > .in-band {
+:target, :target > * {
 	background-color: #494a3d;
-	border-right: 3px solid #bb7410;
 }
 
 pre.compile_fail {

src/librustdoc/html/static/themes/light.css

@@ -275,9 +275,8 @@ a.test-arrow:hover{
 	color: #999;
 }
 
-:target > code, :target > .in-band {
+:target, :target > * {
 	background: #FDFFD3;
-	border-right: 3px solid #ffb44c;
 }
 
 pre.compile_fail {

src/test/rustdoc-gui/src/settings/.package-cache

@@ -13,7 +13,7 @@ pub trait Foo {
 pub struct Bar;
 
 impl Foo for Bar {
-    // @has assoc_consts/struct.Bar.html '//code' 'impl Foo for Bar'
+    // @has assoc_consts/struct.Bar.html '//h3[@class="code-header in-band"]' 'impl Foo for Bar'
     // @has - '//*[@id="associatedconstant.FOO"]' 'const FOO: usize'
     const FOO: usize = 12;
     // @has - '//*[@id="associatedconstant.FOO_NO_DEFAULT"]' 'const FOO_NO_DEFAULT: bool'
@@ -77,7 +77,7 @@ pub trait Qux {
     const QUX_DEFAULT2: u32 = 3;
 }
 
-// @has assoc_consts/struct.Bar.html '//code' 'impl Qux for Bar'
+// @has assoc_consts/struct.Bar.html '//h3[@class="code-header in-band"]' 'impl Qux for Bar'
 impl Qux for Bar {
     // @has - '//*[@id="associatedconstant.QUX0"]' 'const QUX0: u8'
     // @has - '//*[@class="docblock"]' "Docs for QUX0 in trait."

src/test/rustdoc/assoc-consts.rs

@@ -2,11 +2,11 @@
 
 // @has assoc_types/trait.Index.html
 pub trait Index<I: ?Sized> {
-    // @has - '//*[@id="associatedtype.Output"]//code' 'type Output: ?Sized'
+        // @has - '//*[@id="associatedtype.Output"]//h4[@class="code-header"]' 'type Output: ?Sized'
     type Output: ?Sized;
-    // @has - '//*[@id="tymethod.index"]//code' \
+    // @has - '//*[@id="tymethod.index"]//h4[@class="code-header"]' \
     //      "fn index<'a>(&'a self, index: I) -> &'a Self::Output"
-    // @has - '//*[@id="tymethod.index"]//code//a[@href="trait.Index.html#associatedtype.Output"]' \
+    // @has - '//*[@id="tymethod.index"]//h4[@class="code-header"]//a[@href="trait.Index.html#associatedtype.Output"]' \
     //      "Output"
     fn index<'a>(&'a self, index: I) -> &'a Self::Output;
 }