Rollup merge of rust-lang#102521 - notriddle:notriddle/impl-items-section, r=GuillaumeGomez

rustdoc: add missing margin to no-docblock methods

Fixes another regression caused by 8846c08, this time fixing the appearance of methods that have no docblock (we didn't notice this one because libstd docs *always* have docblocks).

See how it looks at https://doc.rust-lang.org/nightly/nightly-rustc/rustdoc/clean/types/enum.Type.html#implementations

<details>

# Before

![image](https://user-images.githubusercontent.com/1593513/193318777-2bc082fb-6579-4bd8-a0e3-d23a32b4820f.png)

# After

![image](https://user-images.githubusercontent.com/1593513/193318968-b6ccacad-940b-4ed3-a0ae-dcf2079c2bae.png)

</details>

See how it looks at https://doc.rust-lang.org/nightly/nightly-rustc/rustdoc/clean/types/trait.AttributesExt.html

<details>

# Before

![image](https://user-images.githubusercontent.com/1593513/193319636-7ff9c99e-0208-462c-99de-7672e92ce4d6.png)

# After

![image](https://user-images.githubusercontent.com/1593513/193322675-403bd165-7394-43e2-8ab4-d1f364666093.png)

</details>

Author: matthiaskrgr

src/librustdoc/html/render/print_item.rs

@@ -718,7 +718,7 @@ fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean:
         if toggled {
             write!(w, "<details class=\"rustdoc-toggle method-toggle\" open><summary>");
         }
-        write!(w, "<div id=\"{}\" class=\"method has-srclink\">", id);
+        write!(w, "<section id=\"{}\" class=\"method has-srclink\">", id);
         render_rightside(w, cx, m, t, RenderMode::Normal);
         write!(w, "<h4 class=\"code-header\">");
         render_assoc_item(
@@ -730,7 +730,7 @@ fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean:
             RenderMode::Normal,
         );
         w.write_str("</h4>");
-        w.write_str("</div>");
+        w.write_str("</section>");
         if toggled {
             write!(w, "</summary>");
             w.push_buffer(content);

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

@@ -2006,7 +2006,10 @@ in storage.js plus the media query with (min-width: 701px)
 .method-toggle summary,
 .implementors-toggle summary,
 .impl,
-#implementors-list > .docblock {
+#implementors-list > .docblock,
+.impl-items > section,
+.methods > section
+{
 	margin-bottom: 0.75em;
 }
 

src/test/rustdoc-gui/no-docblock.goml

@@ -0,0 +1,8 @@
+// This test checks that there are margins applied to methods with no docblocks.
+goto: file://|DOC_PATH|/test_docs/trait.TraitWithNoDocblocks.html
+// Check that the two methods are more than 24px apart.
+compare-elements-position-near-false: ("//*[@id='tymethod.first_fn']", "//*[@id='tymethod.second_fn']", {"y": 24})
+
+goto: file://|DOC_PATH|/test_docs/struct.TypeWithNoDocblocks.html
+// Check that the two methods are more than 24px apart.
+compare-elements-position-near-false: ("//*[@id='method.first_fn']", "//*[@id='method.second_fn']", {"y": 24})

src/test/rustdoc-gui/sidebar-mobile-scroll.goml

@@ -6,7 +6,7 @@ assert-css: (".sidebar", {"display": "block", "left": "-1000px"})
 
 // Scroll down.
 scroll-to: "//h2[@id='blanket-implementations']"
-assert-window-property: {"pageYOffset": "639"}
+assert-window-property: {"pageYOffset": "651"}
 
 // Open the sidebar menu.
 click: ".sidebar-menu-toggle"
@@ -21,11 +21,11 @@ assert-window-property: {"pageYOffset": "0"}
 // Close the sidebar menu. Make sure the scroll position gets restored.
 click: ".sidebar-menu-toggle"
 wait-for-css: (".sidebar", {"left": "-1000px"})
-assert-window-property: {"pageYOffset": "639"}
+assert-window-property: {"pageYOffset": "651"}
 
 // Now test that scrollability returns when the browser window is just resized.
 click: ".sidebar-menu-toggle"
 wait-for-css: (".sidebar", {"left": "0px"})
 assert-window-property: {"pageYOffset": "0"}
 size: (900, 600)
-assert-window-property: {"pageYOffset": "639"}
+assert-window-property: {"pageYOffset": "651"}

src/test/rustdoc-gui/src/test_docs/lib.rs

@@ -355,3 +355,15 @@ impl<R: std::io::Read> std::iter::Iterator for NotableStructWithLongName<R> {
 
     fn next(&mut self) -> Option<Self::Item> { () }
 }
+
+pub trait TraitWithNoDocblocks {
+    fn first_fn(&self);
+    fn second_fn(&self);
+}
+
+pub struct TypeWithNoDocblocks;
+
+impl TypeWithNoDocblocks {
+    pub fn first_fn(&self) {}
+    pub fn second_fn(&self) {}
+}

src/test/rustdoc/anchors.no_const_anchor.html

@@ -1 +1 @@
-<div id="associatedconstant.YOLO" class="method has-srclink"><a class="srclink rightside" href="../src/foo/anchors.rs.html#16">source</a><h4 class="code-header">const <a href="#associatedconstant.YOLO" class="constant">YOLO</a>: <a class="primitive" href="{{channel}}/std/primitive.u32.html">u32</a></h4></div>
+<section id="associatedconstant.YOLO" class="method has-srclink"><a class="srclink rightside" href="../src/foo/anchors.rs.html#16">source</a><h4 class="code-header">const <a href="#associatedconstant.YOLO" class="constant">YOLO</a>: <a class="primitive" href="{{channel}}/std/primitive.u32.html">u32</a></h4></section>

src/test/rustdoc/anchors.no_trait_method_anchor.html

@@ -1 +1 @@
-<div id="method.bar" class="method has-srclink"><a class="srclink rightside" href="../src/foo/anchors.rs.html#23">source</a><h4 class="code-header">fn <a href="#method.bar" class="fnname">bar</a>()</h4></div>
+<section id="method.bar" class="method has-srclink"><a class="srclink rightside" href="../src/foo/anchors.rs.html#23">source</a><h4 class="code-header">fn <a href="#method.bar" class="fnname">bar</a>()</h4></section>

src/test/rustdoc/anchors.no_tymethod_anchor.html

@@ -1 +1 @@
-<div id="tymethod.foo" class="method has-srclink"><a class="srclink rightside" href="../src/foo/anchors.rs.html#20">source</a><h4 class="code-header">fn <a href="#tymethod.foo" class="fnname">foo</a>()</h4></div>
+<section id="tymethod.foo" class="method has-srclink"><a class="srclink rightside" href="../src/foo/anchors.rs.html#20">source</a><h4 class="code-header">fn <a href="#tymethod.foo" class="fnname">foo</a>()</h4></section>

src/test/rustdoc/anchors.no_type_anchor.html

@@ -1 +1 @@
-<div id="associatedtype.T" class="method has-srclink"><a class="srclink rightside" href="../src/foo/anchors.rs.html#13">source</a><h4 class="code-header">type <a href="#associatedtype.T" class="associatedtype">T</a></h4></div>
+<section id="associatedtype.T" class="method has-srclink"><a class="srclink rightside" href="../src/foo/anchors.rs.html#13">source</a><h4 class="code-header">type <a href="#associatedtype.T" class="associatedtype">T</a></h4></section>

src/test/rustdoc/rfc-2632-const-trait-impl.rs

@@ -18,10 +18,10 @@ pub struct S<T>(T);
 // @has - '//pre[@class="rust trait"]/code/span[@class="where"]' ': Clone'
 #[const_trait]
 pub trait Tr<T> {
-    // @!has - '//div[@id="method.a"]/h4[@class="code-header"]' '~const'
-    // @has - '//div[@id="method.a"]/h4[@class="code-header"]/a[@class="trait"]' 'Clone'
-    // @!has - '//div[@id="method.a"]/h4[@class="code-header"]/span[@class="where"]' '~const'
-    // @has - '//div[@id="method.a"]/h4[@class="code-header"]/span[@class="where fmt-newline"]' ': Clone'
+    // @!has - '//section[@id="method.a"]/h4[@class="code-header"]' '~const'
+    // @has - '//section[@id="method.a"]/h4[@class="code-header"]/a[@class="trait"]' 'Clone'
+    // @!has - '//section[@id="method.a"]/h4[@class="code-header"]/span[@class="where"]' '~const'
+    // @has - '//section[@id="method.a"]/h4[@class="code-header"]/span[@class="where fmt-newline"]' ': Clone'
     fn a<A: ~const Clone + ~const Destruct>()
     where
         Option<A>: ~const Clone + ~const Destruct,