Rollup merge of #56874 - JohnHeitmann:docs-spacing, r=GuillaumeGomez

Simplify foreign type rendering.

Simplified foreign type rendering by switching from tables to flexbox. Also, removed some seemingly extraneous elements like “ghost” spans.

Reduces element count on the `std::iter::Iterator` page by 30%. On my laptop it drops Iterator page load time from ~15s to ~10s. Frame times during scrolling are a hair lower too.

Known visual changes (happy to tweak based on feedback):
* The main `impl ...` headers are now getting the default, larger, h3 font size. This was an accident, but I liked how it turned out so I didn't fix it.
* There's a hair less vertical spacing between the end of a where block and the start of the next fn. Now, all spacing is consistent. I think this looks a bit worse. I may tweak vertical spacing more here or in a follow-up that cleans up vertical spacing more broadly.
* "[src]" links are all sized at 17px. A few were 19px in the original.

I haven't yet done heavy cross-browser or cross-crate testing. I was hoping to get a quick thumbs up or thumbs down here at this first draft, then if this is on the right track I'll spend some time on that testing.

TODO:

- [x] Test on Chrome
- [x] Test on Firefox
- [ ] ~~Test on UC Android~~
- [x] Test on Edge
- [x] Test on iOS safari
- [x] Test on desktop safari
- [x] Update automated tests
- [x] Increase vertical margin
- [x] Fix "Important traits for" hover overlap
- [x] Wait for #55798 to land & merge it

16 files changed, 27 insertions, 27 deletions

diff --git a/src/test/rustdoc/assoc-consts-version.rs b/src/test/rustdoc/assoc-consts-version.rs
index 3f3c2516299..c561269cf9a 100644
--- a/src/test/rustdoc/assoc-consts-version.rs
+++ b/src/test/rustdoc/assoc-consts-version.rs
@@ -10,7 +10,7 @@
 pub struct SomeStruct;
 
 impl SomeStruct {
-    // @has 'foo/struct.SomeStruct.html' '//*[@id="SOME_CONST.v"]//div[@class="since"]' '1.1.2'
+    // @has 'foo/struct.SomeStruct.html' '//*[@id="associatedconstant.SOME_CONST"]//div[@class="since"]' '1.1.2'
     #[stable(since="1.1.2", feature="rust2")]
     pub const SOME_CONST: usize = 0;
 }
diff --git a/src/test/rustdoc/const.rs b/src/test/rustdoc/const.rs
index f3118bb6066..c33db5809cc 100644
--- a/src/test/rustdoc/const.rs
+++ b/src/test/rustdoc/const.rs
@@ -3,7 +3,7 @@
 pub struct Foo;
 
 impl Foo {
-    // @has const/struct.Foo.html '//*[@id="new.v"]//code' 'const unsafe fn new'
+    // @has const/struct.Foo.html '//code[@id="new.v"]' 'const unsafe fn new'
     pub const unsafe fn new() -> Foo {
         Foo
     }
diff --git a/src/test/rustdoc/issue-25001.rs b/src/test/rustdoc/issue-25001.rs
index 3c1580f3786..55d8ee39438 100644
--- a/src/test/rustdoc/issue-25001.rs
+++ b/src/test/rustdoc/issue-25001.rs
@@ -9,17 +9,17 @@ pub trait Bar {
 
 impl Foo<u8> {
     // @has - '//*[@id="method.pass"]//code' 'fn pass()'
-    // @has - '//*[@id="pass.v"]//code' 'fn pass()'
+    // @has - '//code[@id="pass.v"]' 'fn pass()'
     pub fn pass() {}
 }
 impl Foo<u16> {
     // @has - '//*[@id="method.pass-1"]//code' 'fn pass() -> usize'
-    // @has - '//*[@id="pass.v-1"]//code' 'fn pass() -> usize'
+    // @has - '//code[@id="pass.v-1"]' 'fn pass() -> usize'
     pub fn pass() -> usize { 42 }
 }
 impl Foo<u32> {
     // @has - '//*[@id="method.pass-2"]//code' 'fn pass() -> isize'
-    // @has - '//*[@id="pass.v-2"]//code' 'fn pass() -> isize'
+    // @has - '//code[@id="pass.v-2"]' 'fn pass() -> isize'
     pub fn pass() -> isize { 42 }
 }
 
diff --git a/src/test/rustdoc/issue-51236.rs b/src/test/rustdoc/issue-51236.rs
index b57a067f3d9..d9accf9c599 100644
--- a/src/test/rustdoc/issue-51236.rs
+++ b/src/test/rustdoc/issue-51236.rs
@@ -7,7 +7,7 @@ pub mod traits {
 }
 
 // @has issue_51236/struct.Owned.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<T> Send for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<T> Send for \
 // Owned<T> where <T as Owned<'static>>::Reader: Send"
 pub struct Owned<T> where T: for<'a> ::traits::Owned<'a> {
     marker: PhantomData<<T as ::traits::Owned<'static>>::Reader>,
diff --git a/src/test/rustdoc/issue-54705.rs b/src/test/rustdoc/issue-54705.rs
index 34f71fab0cc..263b1eb0bd6 100644
--- a/src/test/rustdoc/issue-54705.rs
+++ b/src/test/rustdoc/issue-54705.rs
@@ -3,10 +3,10 @@ pub trait ScopeHandle<'scope> {}
 
 
 // @has issue_54705/struct.ScopeFutureContents.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<'scope, S> \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<'scope, S> \
 // Send for ScopeFutureContents<'scope, S> where S: Sync"
 //
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<'scope, S> \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<'scope, S> \
 // Sync for ScopeFutureContents<'scope, S> where S: Sync"
 pub struct ScopeFutureContents<'scope, S>
     where S: ScopeHandle<'scope>,
diff --git a/src/test/rustdoc/issue-55321.rs b/src/test/rustdoc/issue-55321.rs
index 5c34a4d34ab..257cb32c65c 100644
--- a/src/test/rustdoc/issue-55321.rs
+++ b/src/test/rustdoc/issue-55321.rs
@@ -1,16 +1,16 @@
 #![feature(optin_builtin_traits)]
 
 // @has issue_55321/struct.A.html
-// @has - '//*[@id="implementations-list"]/*[@class="impl"]//*/code' "impl !Send for A"
-// @has - '//*[@id="implementations-list"]/*[@class="impl"]//*/code' "impl !Sync for A"
+// @has - '//*[@id="implementations-list"]/*[@class="impl"]//code' "impl !Send for A"
+// @has - '//*[@id="implementations-list"]/*[@class="impl"]//code' "impl !Sync for A"
 pub struct A();
 
 impl !Send for A {}
 impl !Sync for A {}
 
 // @has issue_55321/struct.B.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<T> !Send for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<T> !Send for \
 // B<T>"
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<T> !Sync for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<T> !Sync for \
 // B<T>"
 pub struct B<T: ?Sized>(A, Box<T>);
diff --git a/src/test/rustdoc/issue-56822.rs b/src/test/rustdoc/issue-56822.rs
index 2d6cb1368d1..5b67817fa4c 100644
--- a/src/test/rustdoc/issue-56822.rs
+++ b/src/test/rustdoc/issue-56822.rs
@@ -17,7 +17,7 @@ impl<'a, T> MyTrait for Inner<'a, T> {
 }
 
 // @has issue_56822/struct.Parser.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<'a> Send for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<'a> Send for \
 // Parser<'a>"
 pub struct Parser<'a> {
     field: <Wrapper<Inner<'a, u8>> as MyTrait>::Output
diff --git a/src/test/rustdoc/synthetic_auto/complex.rs b/src/test/rustdoc/synthetic_auto/complex.rs
index d2533a2dd39..609cefc7115 100644
--- a/src/test/rustdoc/synthetic_auto/complex.rs
+++ b/src/test/rustdoc/synthetic_auto/complex.rs
@@ -20,7 +20,7 @@ mod foo {
 }
 
 // @has complex/struct.NotOuter.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<'a, T, K: \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<'a, T, K: \
 // ?Sized> Send for NotOuter<'a, T, K> where K: for<'b> Fn((&'b bool, &'a u8)) \
 // -> &'b i8, T: MyTrait<'a>, <T as MyTrait<'a>>::MyItem: Copy, 'a: 'static"
 
diff --git a/src/test/rustdoc/synthetic_auto/lifetimes.rs b/src/test/rustdoc/synthetic_auto/lifetimes.rs
index 03b84c7838e..6d0a68f9b07 100644
--- a/src/test/rustdoc/synthetic_auto/lifetimes.rs
+++ b/src/test/rustdoc/synthetic_auto/lifetimes.rs
@@ -9,10 +9,10 @@ where
 {}
 
 // @has lifetimes/struct.Foo.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<'c, K> Send \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<'c, K> Send \
 // for Foo<'c, K> where K: for<'b> Fn(&'b bool) -> &'c u8, 'c: 'static"
 //
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<'c, K> Sync \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<'c, K> Sync \
 // for Foo<'c, K> where K: Sync"
 pub struct Foo<'c, K: 'c> {
     inner_field: Inner<'c, K>,
diff --git a/src/test/rustdoc/synthetic_auto/manual.rs b/src/test/rustdoc/synthetic_auto/manual.rs
index c7cfa0c0fa1..413ba187f45 100644
--- a/src/test/rustdoc/synthetic_auto/manual.rs
+++ b/src/test/rustdoc/synthetic_auto/manual.rs
@@ -1,8 +1,8 @@
 // @has manual/struct.Foo.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' 'impl<T> Sync for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' 'impl<T> Sync for \
 // Foo<T> where T: Sync'
 //
-// @has - '//*[@id="implementations-list"]/*[@class="impl"]//*/code' \
+// @has - '//*[@id="implementations-list"]/*[@class="impl"]//code' \
 // 'impl<T> Send for Foo<T>'
 //
 // @count - '//*[@id="implementations-list"]/*[@class="impl"]' 1
diff --git a/src/test/rustdoc/synthetic_auto/negative.rs b/src/test/rustdoc/synthetic_auto/negative.rs
index 5b6304ed4e4..30713849da2 100644
--- a/src/test/rustdoc/synthetic_auto/negative.rs
+++ b/src/test/rustdoc/synthetic_auto/negative.rs
@@ -3,10 +3,10 @@ pub struct Inner<T: Copy> {
 }
 
 // @has negative/struct.Outer.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<T> !Send for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<T> !Send for \
 // Outer<T>"
 //
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<T> \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<T> \
 // !Sync for Outer<T>"
 pub struct Outer<T: Copy> {
     inner_field: Inner<T>,
diff --git a/src/test/rustdoc/synthetic_auto/nested.rs b/src/test/rustdoc/synthetic_auto/nested.rs
index 75d2ff2af13..e710ce1c2ed 100644
--- a/src/test/rustdoc/synthetic_auto/nested.rs
+++ b/src/test/rustdoc/synthetic_auto/nested.rs
@@ -9,10 +9,10 @@ where
 }
 
 // @has nested/struct.Foo.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' 'impl<T> Send for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' 'impl<T> Send for \
 // Foo<T> where T: Copy'
 //
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' \
 // 'impl<T> Sync for Foo<T> where T: Sync'
 pub struct Foo<T> {
     inner_field: Inner<T>,
diff --git a/src/test/rustdoc/synthetic_auto/no-redundancy.rs b/src/test/rustdoc/synthetic_auto/no-redundancy.rs
index 92402714b9d..cf173111ec1 100644
--- a/src/test/rustdoc/synthetic_auto/no-redundancy.rs
+++ b/src/test/rustdoc/synthetic_auto/no-redundancy.rs
@@ -9,7 +9,7 @@ where
 }
 
 // @has no_redundancy/struct.Outer.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<T> Send for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<T> Send for \
 // Outer<T> where T: Copy + Send"
 pub struct Outer<T> {
     inner_field: Inner<T>,
diff --git a/src/test/rustdoc/synthetic_auto/project.rs b/src/test/rustdoc/synthetic_auto/project.rs
index 6be6b44a440..5346521f8d2 100644
--- a/src/test/rustdoc/synthetic_auto/project.rs
+++ b/src/test/rustdoc/synthetic_auto/project.rs
@@ -23,10 +23,10 @@ where
 }
 
 // @has project/struct.Foo.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<'c, K> Send \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<'c, K> Send \
 // for Foo<'c, K> where K: MyTrait<MyItem = bool>, 'c: 'static"
 //
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<'c, K> Sync \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<'c, K> Sync \
 // for Foo<'c, K> where K: MyTrait, <K as MyTrait>::MyItem: OtherTrait, 'c: 'static,"
 pub struct Foo<'c, K: 'c> {
     inner_field: Inner<'c, K>,
diff --git a/src/test/rustdoc/synthetic_auto/self-referential.rs b/src/test/rustdoc/synthetic_auto/self-referential.rs
index 0dca8fe2978..7d15434afe6 100644
--- a/src/test/rustdoc/synthetic_auto/self-referential.rs
+++ b/src/test/rustdoc/synthetic_auto/self-referential.rs
@@ -23,7 +23,7 @@ impl<T> Pattern for Wrapper<T> {
 
 
 // @has self_referential/struct.WriteAndThen.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<P1> Send for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<P1> Send for \
 // WriteAndThen<P1>  where  <P1 as Pattern>::Value: Send"
 pub struct WriteAndThen<P1>(pub P1::Value,pub <Constrain<P1, Wrapper<P1::Value>> as Pattern>::Value)
     where P1: Pattern;
diff --git a/src/test/rustdoc/synthetic_auto/static-region.rs b/src/test/rustdoc/synthetic_auto/static-region.rs
index d1d50fbc6ba..59493744b62 100644
--- a/src/test/rustdoc/synthetic_auto/static-region.rs
+++ b/src/test/rustdoc/synthetic_auto/static-region.rs
@@ -3,7 +3,7 @@ pub trait OwnedTrait<'a> {
 }
 
 // @has static_region/struct.Owned.html
-// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//*/code' "impl<T> Send for \
+// @has - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]//code' "impl<T> Send for \
 // Owned<T> where <T as OwnedTrait<'static>>::Reader: Send"
 pub struct Owned<T> where T: OwnedTrait<'static> {
     marker: <T as OwnedTrait<'static>>::Reader,