Rustdoc accessibility: use real headers for doc items

Part of #87059

Partially reverts #84703

Preview at: https://notriddle.com/notriddle-rustdoc-test/real-headers/std/index.html

src/librustdoc/html/render/mod.rs

@@ -1194,7 +1194,7 @@ 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)
                         );
@@ -1350,15 +1350,15 @@ fn render_impl(
                     );
                     render_rightside(w, cx, item, containing_item);
                     write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
-                    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>");
                     w.write_str("</div>");
                 }
             }
@@ -1371,7 +1371,7 @@ fn render_impl(
                     id, item_type, in_trait_class
                 );
                 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
-                w.write_str("<code>");
+                w.write_str("<h4 class=\"code-header\">");
                 assoc_type(
                     w,
                     item,
@@ -1381,7 +1381,7 @@ fn render_impl(
                     "",
                     cx,
                 );
-                w.write_str("</code>");
+                w.write_str("</h4>");
                 w.write_str("</div>");
             }
             clean::AssocConstItem(ref ty, ref default) => {
@@ -1394,7 +1394,7 @@ fn render_impl(
                 );
                 render_rightside(w, cx, item, containing_item);
                 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
-                w.write_str("<code>");
+                w.write_str("<h4 class=\"code-header\">");
                 assoc_const(
                     w,
                     item,
@@ -1404,15 +1404,15 @@ fn render_impl(
                     "",
                     cx,
                 );
-                w.write_str("</code>");
+                w.write_str("</h4>");
                 w.write_str("</div>");
             }
             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=\"{}{}\">", id, item_type, in_trait_class,);
                 write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
-                w.write_str("<code>");
+                w.write_str("<h4 class=\"code-header\">");
                 assoc_type(
                     w,
                     item,
@@ -1422,7 +1422,7 @@ fn render_impl(
                     "",
                     cx,
                 );
-                w.write_str("</code>");
+                w.write_str("</h4>");
                 w.write_str("</div>");
             }
             clean::StrippedItem(..) => return,
@@ -1613,7 +1613,7 @@ pub(crate) fn render_impl_summary(
     write!(w, "<div id=\"{}\" class=\"impl has-srclink\"{}>", id, aliases);
     render_rightside(w, cx, &i.impl_item, containing_item);
     write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
-    write!(w, "<code class=\"in-band\">");
+    write!(w, "<h3 class=\"code-header in-band\">");
 
     if let Some(use_absolute) = use_absolute {
         write!(w, "{}", i.inner_impl().print(use_absolute, cx));
@@ -1629,7 +1629,7 @@ pub(crate) fn render_impl_summary(
     } else {
         write!(w, "{}", i.inner_impl().print(false, cx));
     }
-    write!(w, "</code>");
+    write!(w, "</h3>");
 
     let is_trait = i.inner_impl().trait_.is_some();
     if is_trait {

src/librustdoc/html/render/print_item.rs

@@ -621,9 +621,9 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
         render_stability_since(w, m, t, cx.tcx());
         write_srclink(cx, m, w);
         write!(w, "</div>");
-        write!(w, "<code>");
+        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>");
         w.write_str("</div>");
         if toggled {
             write!(w, "</summary>");

src/librustdoc/html/static/css/rustdoc.css

@@ -146,6 +146,13 @@ h1.fqn > .in-band > a:hover {
 h2, h3, h4 {
 	border-bottom: 1px solid;
 }
+h3.code-header, h4.code-header {
+	font-size: 1em;
+	font-weight: 600;
+	border: none;
+	padding: 0;
+	margin: 0;
+}
 .impl,
 .impl-items .method,
 .methods .method,
@@ -233,7 +240,7 @@ details:not(.rustdoc-toggle) summary {
 	margin-bottom: .6em;
 }
 
-code, pre, a.test-arrow {
+code, pre, a.test-arrow, .code-header {
 	font-family: "Source Code Pro", monospace;
 }
 .docblock code, .docblock-short code {
@@ -520,7 +527,7 @@ 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;
 }
@@ -536,7 +543,7 @@ nav.sub {
 	padding: 0px;
 }
 
-.in-band > code {
+.in-band > code, .in-band > .code-header {
 	display: inline-block;
 }
 
@@ -742,7 +749,7 @@ a {
 }
 
 .invisible > .srclink,
-.method > code + .srclink {
+.method > .code-header + .srclink {
 	position: absolute;
 	top: 0;
 	right: 0;
@@ -1103,7 +1110,7 @@ a.test-arrow:hover{
 	left: -10px;
 }
 
-:target > code {
+:target > code, :target > .code-header {
 	opacity: 1;
 }
 

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

@@ -334,7 +334,7 @@ a.test-arrow:hover {
 	color: #999;
 }
 
-:target, :target * {
+:target, :target > * {
 	background: rgba(255, 236, 164, 0.06);
 }
 

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

@@ -282,7 +282,7 @@ a.test-arrow:hover{
 	color: #999;
 }
 
-:target, :target * {
+:target, :target > * {
 	background-color: #494a3d;
 }
 

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

@@ -274,7 +274,7 @@ a.test-arrow:hover{
 	color: #999;
 }
 
-:target, :target * {
+:target, :target > * {
 	background: #FDFFD3;
 }
 

src/librustdoc/html/static/js/main.js

@@ -706,8 +706,9 @@ 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) {

src/test/rustdoc-gui/font-weight.goml

@@ -2,9 +2,9 @@ goto: file://|DOC_PATH|/lib2/struct.Foo.html
 // This test checks that the font weight is correctly applied.
 assert-css: ("//*[@class='docblock type-decl']//a[text()='Alias']", {"font-weight": "400"})
 assert-css: ("//*[@class='structfield small-section-header']//a[text()='Alias']", {"font-weight": "400"})
-assert-css: ("#method\.a_method > code", {"font-weight": "600"})
-assert-css: ("#associatedtype\.X > code", {"font-weight": "600"})
-assert-css: ("#associatedconstant\.Y > code", {"font-weight": "600"})
+assert-css: ("#method\.a_method > .code-header", {"font-weight": "600"})
+assert-css: ("#associatedtype\.X > .code-header", {"font-weight": "600"})
+assert-css: ("#associatedconstant\.Y > .code-header", {"font-weight": "600"})
 
 goto: file://|DOC_PATH|/test_docs/type.SomeType.html
 assert-css: (".top-doc .docblock p", {"font-weight": "400"}, ALL)

src/test/rustdoc-gui/implementors.goml

@@ -8,9 +8,9 @@ assert-count: ("#implementors-list > .impl", 2)
 assert: ("#implementors-list > .impl:nth-child(1) > a.anchor")
 assert-attribute: ("#implementors-list > .impl:nth-child(1)", {"id": "impl-Whatever"})
 assert-attribute: ("#implementors-list > .impl:nth-child(1) > a.anchor", {"href": "#impl-Whatever"})
-assert: "#implementors-list > .impl:nth-child(1) > code.in-band"
+assert: "#implementors-list > .impl:nth-child(1) > .code-header.in-band"
 
 assert: ("#implementors-list > .impl:nth-child(2) > a.anchor")
 assert-attribute: ("#implementors-list > .impl:nth-child(2)", {"id": "impl-Whatever-1"})
 assert-attribute: ("#implementors-list > .impl:nth-child(2) > a.anchor", {"href": "#impl-Whatever-1"})
-assert: "#implementors-list > .impl:nth-child(2) > code.in-band"
+assert: "#implementors-list > .impl:nth-child(2) > .code-header.in-band"

src/test/rustdoc/assoc-consts.rs

@@ -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-types.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;
 }

src/test/rustdoc/async-fn.rs

@@ -35,9 +35,9 @@ pub async fn quux() -> impl Bar {
 }
 
 // @has async_fn/struct.Foo.html
-// @matches - '//code' 'pub async fn f\(\)$'
-// @matches - '//code' 'pub async unsafe fn g\(\)$'
-// @matches - '//code' 'pub async fn mut_self\(self, first: usize\)$'
+// @matches - '//h4[@class="code-header"]' 'pub async fn f\(\)$'
+// @matches - '//h4[@class="code-header"]' 'pub async unsafe fn g\(\)$'
+// @matches - '//h4[@class="code-header"]' 'pub async fn mut_self\(self, first: usize\)$'
 pub struct Foo;
 
 impl Foo {

src/test/rustdoc/blanket-reexport-item.rs

@@ -1,6 +1,6 @@
 #![crate_name = "foo"]
 
-// @has foo/struct.S.html '//div[@id="impl-Into%3CU%3E"]//code' 'impl<T, U> Into<U> for T'
+// @has foo/struct.S.html '//div[@id="impl-Into%3CU%3E"]//h3[@class="code-header in-band"]' 'impl<T, U> Into<U> for T'
 pub struct S2 {}
 mod m {
     pub struct S {}

src/test/rustdoc/const-display.rs

@@ -49,19 +49,19 @@ pub const unsafe fn bar_not_gated() -> u32 { 42 }
 pub struct Foo;
 
 impl Foo {
-    // @has 'foo/struct.Foo.html' '//div[@id="method.gated"]/code' 'pub fn gated() -> u32'
+    // @has 'foo/struct.Foo.html' '//div[@id="method.gated"]/h4[@class="code-header"]' 'pub fn gated() -> u32'
     // @has - '//span[@class="since"]' '1.0.0 (const: unstable)'
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature="foo", issue = "none")]
     pub const fn gated() -> u32 { 42 }
 
-    // @has 'foo/struct.Foo.html' '//div[@id="method.gated_unsafe"]/code' 'pub unsafe fn gated_unsafe() -> u32'
+    // @has 'foo/struct.Foo.html' '//div[@id="method.gated_unsafe"]/h4[@class="code-header"]' 'pub unsafe fn gated_unsafe() -> u32'
     // @has - '//span[@class="since"]' '1.0.0 (const: unstable)'
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature="foo", issue = "none")]
     pub const unsafe fn gated_unsafe() -> u32 { 42 }
 
-    // @has 'foo/struct.Foo.html' '//div[@id="method.stable_impl"]/code' 'pub const fn stable_impl() -> u32'
+    // @has 'foo/struct.Foo.html' '//div[@id="method.stable_impl"]/h4[@class="code-header"]' 'pub const fn stable_impl() -> u32'
     // @has - '//span[@class="since"]' '1.0.0 (const: 1.2.0)'
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_stable(feature = "rust1", since = "1.2.0")]

src/test/rustdoc/const-generics/add-impl.rs

@@ -8,7 +8,7 @@ pub struct Simd<T, const WIDTH: usize> {
     inner: T,
 }
 
-// @has foo/struct.Simd.html '//div[@id="trait-implementations-list"]//div/code' 'impl Add<Simd<u8, 16_usize>> for Simd<u8, 16>'
+// @has foo/struct.Simd.html '//div[@id="trait-implementations-list"]//div/h3[@class="code-header in-band"]' 'impl Add<Simd<u8, 16_usize>> for Simd<u8, 16>'
 impl Add for Simd<u8, 16> {
     type Output = Self;
 

src/test/rustdoc/const-generics/const-generics-docs.rs

@@ -19,10 +19,10 @@ pub use extern_crate::WTrait;
 
 // @has foo/trait.Trait.html '//pre[@class="rust trait"]' \
 //      'pub trait Trait<const N: usize>'
-// @has - '//*[@id="impl-Trait%3C1_usize%3E-for-u8"]//code' 'impl Trait<1_usize> for u8'
-// @has - '//*[@id="impl-Trait%3C2_usize%3E-for-u8"]//code' 'impl Trait<2_usize> for u8'
-// @has - '//*[@id="impl-Trait%3C{1%20+%202}%3E-for-u8"]//code' 'impl Trait<{1 + 2}> for u8'
-// @has - '//*[@id="impl-Trait%3CN%3E-for-%5Bu8%3B%20N%5D"]//code' \
+// @has - '//*[@id="impl-Trait%3C1_usize%3E-for-u8"]//h3[@class="code-header in-band"]' 'impl Trait<1_usize> for u8'
+// @has - '//*[@id="impl-Trait%3C2_usize%3E-for-u8"]//h3[@class="code-header in-band"]' 'impl Trait<2_usize> for u8'
+// @has - '//*[@id="impl-Trait%3C{1%20+%202}%3E-for-u8"]//h3[@class="code-header in-band"]' 'impl Trait<{1 + 2}> for u8'
+// @has - '//*[@id="impl-Trait%3CN%3E-for-%5Bu8%3B%20N%5D"]//h3[@class="code-header in-band"]' \
 //      'impl<const N: usize> Trait<N> for [u8; N]'
 pub trait Trait<const N: usize> {}
 impl Trait<1> for u8 {}
@@ -36,7 +36,7 @@ pub struct Foo<const N: usize> where u8: Trait<N>;
 // @has foo/struct.Bar.html '//pre[@class="rust struct"]' 'pub struct Bar<T, const N: usize>(_)'
 pub struct Bar<T, const N: usize>([T; N]);
 
-// @has foo/struct.Foo.html '//div[@id="impl"]/code' 'impl<const M: usize> Foo<M> where u8: Trait<M>'
+// @has foo/struct.Foo.html '//div[@id="impl"]/h3[@class="code-header in-band"]' 'impl<const M: usize> Foo<M> where u8: Trait<M>'
 impl<const M: usize> Foo<M> where u8: Trait<M> {
     // @has - '//*[@id="associatedconstant.FOO_ASSOC"]' 'pub const FOO_ASSOC: usize'
     pub const FOO_ASSOC: usize = M + 13;
@@ -47,7 +47,7 @@ impl<const M: usize> Foo<M> where u8: Trait<M> {
     }
 }
 
-// @has foo/struct.Bar.html '//div[@id="impl"]/code' 'impl<const M: usize> Bar<u8, M>'
+// @has foo/struct.Bar.html '//div[@id="impl"]/h3[@class="code-header in-band"]' 'impl<const M: usize> Bar<u8, M>'
 impl<const M: usize> Bar<u8, M> {
     // @has - '//*[@id="method.hey"]' \
     //      'pub fn hey<const N: usize>(&self) -> Foo<N> where u8: Trait<N>'

src/test/rustdoc/const-generics/const-impl.rs

@@ -9,20 +9,20 @@ pub enum Order {
 }
 
 // @has foo/struct.VSet.html '//pre[@class="rust struct"]' 'pub struct VSet<T, const ORDER: Order>'
-// @has foo/struct.VSet.html '//div[@id="impl-Send"]/code' 'impl<T, const ORDER: Order> Send for VSet<T, ORDER>'
-// @has foo/struct.VSet.html '//div[@id="impl-Sync"]/code' 'impl<T, const ORDER: Order> Sync for VSet<T, ORDER>'
+// @has foo/struct.VSet.html '//div[@id="impl-Send"]/h3[@class="code-header in-band"]' 'impl<T, const ORDER: Order> Send for VSet<T, ORDER>'
+// @has foo/struct.VSet.html '//div[@id="impl-Sync"]/h3[@class="code-header in-band"]' 'impl<T, const ORDER: Order> Sync for VSet<T, ORDER>'
 pub struct VSet<T, const ORDER: Order> {
     inner: Vec<T>,
 }
 
-// @has foo/struct.VSet.html '//div[@id="impl"]/code' 'impl<T> VSet<T, {Order::Sorted}>'
+// @has foo/struct.VSet.html '//div[@id="impl"]/h3[@class="code-header in-band"]' 'impl<T> VSet<T, {Order::Sorted}>'
 impl <T> VSet<T, {Order::Sorted}> {
     pub fn new() -> Self {
         Self { inner: Vec::new() }
     }
 }
 
-// @has foo/struct.VSet.html '//div[@id="impl-1"]/code' 'impl<T> VSet<T, {Order::Unsorted}>'
+// @has foo/struct.VSet.html '//div[@id="impl-1"]/h3[@class="code-header in-band"]' 'impl<T> VSet<T, {Order::Unsorted}>'
 impl <T> VSet<T, {Order::Unsorted}> {
     pub fn new() -> Self {
         Self { inner: Vec::new() }
@@ -31,7 +31,7 @@ impl <T> VSet<T, {Order::Unsorted}> {
 
 pub struct Escape<const S: &'static str>;
 
-// @has foo/struct.Escape.html '//div[@id="impl"]/code' 'impl Escape<{ r#"<script>alert("Escape");</script>"# }>'
+// @has foo/struct.Escape.html '//div[@id="impl"]/h3[@class="code-header in-band"]' 'impl Escape<{ r#"<script>alert("Escape");</script>"# }>'
 impl Escape<{ r#"<script>alert("Escape");</script>"# }> {
     pub fn f() {}
 }

src/test/rustdoc/const-generics/lazy_normalization_consts/const-equate-pred.rs

@@ -12,7 +12,7 @@ pub struct Hasher<T> {
 unsafe impl<T: Default> Send for Hasher<T> {}
 
 // @has foo/struct.Foo.html
-// @has - '//code' 'impl Send for Foo'
+// @has - '//h3[@class="code-header in-band"]' 'impl Send for Foo'
 pub struct Foo {
     hasher: Hasher<[u8; 3]>,
 }