Auto merge of #129985 - matthiaskrgr:rollup-trpflqk, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #129529 (Add test to build crates used by r-a on stable)
 - #129624 (Adjust `memchr` pinning and run `cargo update`)
 - #129720 (Simplify DestProp memory management)
 - #129796 (Unify scraped examples with other code examples)
 - #129891 (Do not request sanitizers for naked functions)
 - #129938 (Elaborate on deriving vs implementing `Copy`)

Failed merges:

 - #129471 ([rustdoc] Sort impl associated items by kinds and then by appearance)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

Cargo.lock

@@ -4,10 +4,9 @@ version = "0.0.0"
 edition = "2021"
 
 [dependencies]
-# FIXME: bumping memchr to 2.7.1 causes linker errors in MSVC thin-lto
 # tidy-alphabetical-start
 bitflags = "2.4.1"
-memchr = "=2.5.0"
+memchr = "2.7.4"
 rustc_ast_ir = { path = "../rustc_ast_ir" }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_index = { path = "../rustc_index" }

compiler/rustc_ast/Cargo.toml

@@ -411,26 +411,31 @@ pub(crate) fn llfn_attrs_from_instance<'ll, 'tcx>(
             // the string "false". Now it is disabled by absence of the attribute.
             to_add.push(llvm::CreateAttrStringValue(cx.llcx, "branch-target-enforcement", "false"));
         }
-    } else if llvm_util::get_version() >= (19, 0, 0) {
-        // For non-naked functions, set branch protection attributes on aarch64.
-        if let Some(BranchProtection { bti, pac_ret }) =
-            cx.sess().opts.unstable_opts.branch_protection
-        {
-            assert!(cx.sess().target.arch == "aarch64");
-            if bti {
-                to_add.push(llvm::CreateAttrString(cx.llcx, "branch-target-enforcement"));
-            }
-            if let Some(PacRet { leaf, key }) = pac_ret {
-                to_add.push(llvm::CreateAttrStringValue(
-                    cx.llcx,
-                    "sign-return-address",
-                    if leaf { "all" } else { "non-leaf" },
-                ));
-                to_add.push(llvm::CreateAttrStringValue(
-                    cx.llcx,
-                    "sign-return-address-key",
-                    if key == PAuthKey::A { "a_key" } else { "b_key" },
-                ));
+    } else {
+        // Do not set sanitizer attributes for naked functions.
+        to_add.extend(sanitize_attrs(cx, codegen_fn_attrs.no_sanitize));
+
+        if llvm_util::get_version() >= (19, 0, 0) {
+            // For non-naked functions, set branch protection attributes on aarch64.
+            if let Some(BranchProtection { bti, pac_ret }) =
+                cx.sess().opts.unstable_opts.branch_protection
+            {
+                assert!(cx.sess().target.arch == "aarch64");
+                if bti {
+                    to_add.push(llvm::CreateAttrString(cx.llcx, "branch-target-enforcement"));
+                }
+                if let Some(PacRet { leaf, key }) = pac_ret {
+                    to_add.push(llvm::CreateAttrStringValue(
+                        cx.llcx,
+                        "sign-return-address",
+                        if leaf { "all" } else { "non-leaf" },
+                    ));
+                    to_add.push(llvm::CreateAttrStringValue(
+                        cx.llcx,
+                        "sign-return-address-key",
+                        if key == PAuthKey::A { "a_key" } else { "b_key" },
+                    ));
+                }
             }
         }
     }
@@ -485,7 +490,6 @@ pub(crate) fn llfn_attrs_from_instance<'ll, 'tcx>(
     if let Some(backchain) = backchain_attr(cx) {
         to_add.push(backchain);
     }
-    to_add.extend(sanitize_attrs(cx, codegen_fn_attrs.no_sanitize));
     to_add.extend(patchable_function_entry_attrs(cx, codegen_fn_attrs.patchable_function_entry));
 
     // Always annotate functions with the target-cpu they are compiled for.

compiler/rustc_codegen_llvm/src/attributes.rs

@@ -163,7 +163,8 @@ impl<'tcx> crate::MirPass<'tcx> for DestinationPropagation {
 
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         let def_id = body.source.def_id();
-        let mut allocations = Allocations::default();
+        let mut candidates = Candidates::default();
+        let mut write_info = WriteInfo::default();
         trace!(func = ?tcx.def_path_str(def_id));
 
         let borrowed = rustc_mir_dataflow::impls::borrowed_locals(body);
@@ -191,20 +192,15 @@ impl<'tcx> crate::MirPass<'tcx> for DestinationPropagation {
         loop {
             // PERF: Can we do something smarter than recalculating the candidates and liveness
             // results?
-            let mut candidates = find_candidates(
-                body,
-                &borrowed,
-                &mut allocations.candidates,
-                &mut allocations.candidates_reverse,
-            );
+            candidates.reset_and_find(body, &borrowed);
             trace!(?candidates);
             dest_prop_mir_dump(tcx, body, &points, &live, round_count);
 
             FilterInformation::filter_liveness(
                 &mut candidates,
                 &points,
                 &live,
-                &mut allocations.write_info,
+                &mut write_info,
                 body,
             );
 
@@ -253,20 +249,8 @@ impl<'tcx> crate::MirPass<'tcx> for DestinationPropagation {
     }
 }
 
-/// Container for the various allocations that we need.
-///
-/// We store these here and hand out `&mut` access to them, instead of dropping and recreating them
-/// frequently. Everything with a `&'alloc` lifetime points into here.
-#[derive(Default)]
-struct Allocations {
-    candidates: FxIndexMap<Local, Vec<Local>>,
-    candidates_reverse: FxIndexMap<Local, Vec<Local>>,
-    write_info: WriteInfo,
-    // PERF: Do this for `MaybeLiveLocals` allocations too.
-}
-
-#[derive(Debug)]
-struct Candidates<'alloc> {
+#[derive(Debug, Default)]
+struct Candidates {
     /// The set of candidates we are considering in this optimization.
     ///
     /// We will always merge the key into at most one of its values.
@@ -281,11 +265,12 @@ struct Candidates<'alloc> {
     ///
     /// We will still report that we would like to merge `_1` and `_2` in an attempt to allow us to
     /// remove that assignment.
-    c: &'alloc mut FxIndexMap<Local, Vec<Local>>,
+    c: FxIndexMap<Local, Vec<Local>>,
+
     /// A reverse index of the `c` set; if the `c` set contains `a => Place { local: b, proj }`,
     /// then this contains `b => a`.
     // PERF: Possibly these should be `SmallVec`s?
-    reverse: &'alloc mut FxIndexMap<Local, Vec<Local>>,
+    reverse: FxIndexMap<Local, Vec<Local>>,
 }
 
 //////////////////////////////////////////////////////////
@@ -358,19 +343,40 @@ impl<'a, 'tcx> MutVisitor<'tcx> for Merger<'a, 'tcx> {
 //
 // This section enforces bullet point 2
 
-struct FilterInformation<'a, 'body, 'alloc, 'tcx> {
-    body: &'body Body<'tcx>,
+struct FilterInformation<'a, 'tcx> {
+    body: &'a Body<'tcx>,
     points: &'a DenseLocationMap,
     live: &'a SparseIntervalMatrix<Local, PointIndex>,
-    candidates: &'a mut Candidates<'alloc>,
-    write_info: &'alloc mut WriteInfo,
+    candidates: &'a mut Candidates,
+    write_info: &'a mut WriteInfo,
     at: Location,
 }
 
 // We first implement some utility functions which we will expose removing candidates according to
 // different needs. Throughout the liveness filtering, the `candidates` are only ever accessed
 // through these methods, and not directly.
-impl<'alloc> Candidates<'alloc> {
+impl Candidates {
+    /// Collects the candidates for merging.
+    ///
+    /// This is responsible for enforcing the first and third bullet point.
+    fn reset_and_find<'tcx>(&mut self, body: &Body<'tcx>, borrowed: &BitSet<Local>) {
+        self.c.clear();
+        self.reverse.clear();
+        let mut visitor = FindAssignments { body, candidates: &mut self.c, borrowed };
+        visitor.visit_body(body);
+        // Deduplicate candidates.
+        for (_, cands) in self.c.iter_mut() {
+            cands.sort();
+            cands.dedup();
+        }
+        // Generate the reverse map.
+        for (src, cands) in self.c.iter() {
+            for dest in cands.iter().copied() {
+                self.reverse.entry(dest).or_default().push(*src);
+            }
+        }
+    }
+
     /// Just `Vec::retain`, but the condition is inverted and we add debugging output
     fn vec_filter_candidates(
         src: Local,
@@ -445,7 +451,7 @@ enum CandidateFilter {
     Remove,
 }
 
-impl<'a, 'body, 'alloc, 'tcx> FilterInformation<'a, 'body, 'alloc, 'tcx> {
+impl<'a, 'tcx> FilterInformation<'a, 'tcx> {
     /// Filters the set of candidates to remove those that conflict.
     ///
     /// The steps we take are exactly those that are outlined at the top of the file. For each
@@ -463,12 +469,12 @@ impl<'a, 'body, 'alloc, 'tcx> FilterInformation<'a, 'body, 'alloc, 'tcx> {
     /// before the statement/terminator will correctly report locals that are read in the
     /// statement/terminator to be live. We are additionally conservative by treating all written to
     /// locals as also being read from.
-    fn filter_liveness<'b>(
-        candidates: &mut Candidates<'alloc>,
+    fn filter_liveness(
+        candidates: &mut Candidates,
         points: &DenseLocationMap,
         live: &SparseIntervalMatrix<Local, PointIndex>,
-        write_info_alloc: &'alloc mut WriteInfo,
-        body: &'b Body<'tcx>,
+        write_info: &mut WriteInfo,
+        body: &Body<'tcx>,
     ) {
         let mut this = FilterInformation {
             body,
@@ -477,7 +483,7 @@ impl<'a, 'body, 'alloc, 'tcx> FilterInformation<'a, 'body, 'alloc, 'tcx> {
             candidates,
             // We don't actually store anything at this scope, we just keep things here to be able
             // to reuse the allocation.
-            write_info: write_info_alloc,
+            write_info,
             // Doesn't matter what we put here, will be overwritten before being used
             at: Location::START,
         };
@@ -734,40 +740,13 @@ fn places_to_candidate_pair<'tcx>(
     Some((a, b))
 }
 
-/// Collects the candidates for merging
-///
-/// This is responsible for enforcing the first and third bullet point.
-fn find_candidates<'alloc, 'tcx>(
-    body: &Body<'tcx>,
-    borrowed: &BitSet<Local>,
-    candidates: &'alloc mut FxIndexMap<Local, Vec<Local>>,
-    candidates_reverse: &'alloc mut FxIndexMap<Local, Vec<Local>>,
-) -> Candidates<'alloc> {
-    candidates.clear();
-    candidates_reverse.clear();
-    let mut visitor = FindAssignments { body, candidates, borrowed };
-    visitor.visit_body(body);
-    // Deduplicate candidates
-    for (_, cands) in candidates.iter_mut() {
-        cands.sort();
-        cands.dedup();
-    }
-    // Generate the reverse map
-    for (src, cands) in candidates.iter() {
-        for dest in cands.iter().copied() {
-            candidates_reverse.entry(dest).or_default().push(*src);
-        }
-    }
-    Candidates { c: candidates, reverse: candidates_reverse }
-}
-
-struct FindAssignments<'a, 'alloc, 'tcx> {
+struct FindAssignments<'a, 'tcx> {
     body: &'a Body<'tcx>,
-    candidates: &'alloc mut FxIndexMap<Local, Vec<Local>>,
+    candidates: &'a mut FxIndexMap<Local, Vec<Local>>,
     borrowed: &'a BitSet<Local>,
 }
 
-impl<'tcx> Visitor<'tcx> for FindAssignments<'_, '_, 'tcx> {
+impl<'tcx> Visitor<'tcx> for FindAssignments<'_, 'tcx> {
     fn visit_statement(&mut self, statement: &Statement<'tcx>, _: Location) {
         if let StatementKind::Assign(box (
             lhs,
@@ -819,9 +798,9 @@ fn is_local_required(local: Local, body: &Body<'_>) -> bool {
 /////////////////////////////////////////////////////////
 // MIR Dump
 
-fn dest_prop_mir_dump<'body, 'tcx>(
+fn dest_prop_mir_dump<'tcx>(
     tcx: TyCtxt<'tcx>,
-    body: &'body Body<'tcx>,
+    body: &Body<'tcx>,
     points: &DenseLocationMap,
     live: &SparseIntervalMatrix<Local, PointIndex>,
     round: usize,

compiler/rustc_mir_transform/src/dest_prop.rs

@@ -237,7 +237,7 @@ pub fn supertrait_def_ids<I: Interner>(
     cx: I,
     trait_def_id: I::DefId,
 ) -> impl Iterator<Item = I::DefId> {
-    let mut set: HashSet<I::DefId> = HashSet::default();
+    let mut set = HashSet::default();
     let mut stack = vec![trait_def_id];
 
     set.insert(trait_def_id);

library/Cargo.lock

@@ -288,8 +288,19 @@ marker_impls! {
 /// }
 /// ```
 ///
-/// There is a small difference between the two: the `derive` strategy will also place a `Copy`
-/// bound on type parameters, which isn't always desired.
+/// There is a small difference between the two. The `derive` strategy will also place a `Copy`
+/// bound on type parameters:
+///
+/// ```
+/// #[derive(Clone)]
+/// struct MyStruct<T>(T);
+///
+/// impl<T: Copy> Copy for MyStruct<T> { }
+/// ```
+///
+/// This isn't always desired. For example, shared references (`&T`) can be copied regardless of
+/// whether `T` is `Copy`. Likewise, a generic struct containing markers such as [`PhantomData`]
+/// could potentially be duplicated with a bit-wise copy.
 ///
 /// ## What's the difference between `Copy` and `Clone`?
 ///

library/core/src/marker.rs

@@ -23,6 +23,10 @@ unwind = { path = "../unwind" }
 hashbrown = { version = "0.14", default-features = false, features = [
     'rustc-dep-of-std',
 ] }
+# FIXME(#127890): `object` depends on `memchr`, but `memchr` > v2.5 causes
+# issues with LTO. This dependency is not used directly, but pin it here so
+# it is resolved 2.5. To be removed once rust-lang/rust#127890 is fixed.
+memchr = { version = "=2.5.0", default-features = false, features = ["rustc-dep-of-std"] }
 std_detect = { path = "../stdarch/crates/std_detect", default-features = false, features = [
     'rustc-dep-of-std',
 ] }

library/std/Cargo.toml

@@ -2455,28 +2455,6 @@ fn render_call_locations<W: fmt::Write>(mut w: W, cx: &mut Context<'_>, item: &c
         let needs_expansion = line_max - line_min > NUM_VISIBLE_LINES;
         let locations_encoded = serde_json::to_string(&line_ranges).unwrap();
 
-        write!(
-            &mut w,
-            "<div class=\"scraped-example {expanded_cls}\" data-locs=\"{locations}\">\
-                <div class=\"scraped-example-title\">\
-                   {name} (<a href=\"{url}\">{title}</a>)\
-                </div>\
-                <div class=\"code-wrapper\">",
-            expanded_cls = if needs_expansion { "" } else { "expanded" },
-            name = call_data.display_name,
-            url = init_url,
-            title = init_title,
-            // The locations are encoded as a data attribute, so they can be read
-            // later by the JS for interactions.
-            locations = Escape(&locations_encoded)
-        )
-        .unwrap();
-
-        if line_ranges.len() > 1 {
-            w.write_str(r#"<button class="prev">&pr;</button> <button class="next">&sc;</button>"#)
-                .unwrap();
-        }
-
         // Look for the example file in the source map if it exists, otherwise return a dummy span
         let file_span = (|| {
             let source_map = tcx.sess.source_map();
@@ -2507,9 +2485,16 @@ fn render_call_locations<W: fmt::Write>(mut w: W, cx: &mut Context<'_>, item: &c
             cx,
             &cx.root_path(),
             highlight::DecorationInfo(decoration_info),
-            sources::SourceContext::Embedded { offset: line_min, needs_expansion },
+            sources::SourceContext::Embedded(sources::ScrapedInfo {
+                needs_prev_next_buttons: line_ranges.len() > 1,
+                needs_expansion,
+                offset: line_min,
+                name: &call_data.display_name,
+                url: init_url,
+                title: init_title,
+                locations: locations_encoded,
+            }),
         );
-        w.write_str("</div></div>").unwrap();
 
         true
     };

src/librustdoc/html/render/mod.rs

@@ -290,9 +290,34 @@ where
     }
 }
 
-pub(crate) enum SourceContext {
+pub(crate) struct ScrapedInfo<'a> {
+    pub(crate) offset: usize,
+    pub(crate) needs_prev_next_buttons: bool,
+    pub(crate) name: &'a str,
+    pub(crate) url: &'a str,
+    pub(crate) title: &'a str,
+    pub(crate) locations: String,
+    pub(crate) needs_expansion: bool,
+}
+
+#[derive(Template)]
+#[template(path = "scraped_source.html")]
+struct ScrapedSource<'a, Code: std::fmt::Display> {
+    info: ScrapedInfo<'a>,
+    lines: RangeInclusive<usize>,
+    code_html: Code,
+}
+
+#[derive(Template)]
+#[template(path = "source.html")]
+struct Source<Code: std::fmt::Display> {
+    lines: RangeInclusive<usize>,
+    code_html: Code,
+}
+
+pub(crate) enum SourceContext<'a> {
     Standalone,
-    Embedded { offset: usize, needs_expansion: bool },
+    Embedded(ScrapedInfo<'a>),
 }
 
 /// Wrapper struct to render the source code of a file. This will do things like
@@ -304,23 +329,8 @@ pub(crate) fn print_src(
     context: &Context<'_>,
     root_path: &str,
     decoration_info: highlight::DecorationInfo,
-    source_context: SourceContext,
+    source_context: SourceContext<'_>,
 ) {
-    #[derive(Template)]
-    #[template(path = "source.html")]
-    struct Source<Code: std::fmt::Display> {
-        embedded: bool,
-        needs_expansion: bool,
-        lines: RangeInclusive<usize>,
-        code_html: Code,
-    }
-    let lines = s.lines().count();
-    let (embedded, needs_expansion, lines) = match source_context {
-        SourceContext::Standalone => (false, false, 1..=lines),
-        SourceContext::Embedded { offset, needs_expansion } => {
-            (true, needs_expansion, (1 + offset)..=(lines + offset))
-        }
-    };
     let current_href = context
         .href_from_span(clean::Span::new(file_span), false)
         .expect("only local crates should have sources emitted");
@@ -333,5 +343,14 @@ pub(crate) fn print_src(
         );
         Ok(())
     });
-    Source { embedded, needs_expansion, lines, code_html: code }.render_into(&mut writer).unwrap();
+    let lines = s.lines().count();
+    match source_context {
+        SourceContext::Standalone => {
+            Source { lines: (1..=lines), code_html: code }.render_into(&mut writer).unwrap()
+        }
+        SourceContext::Embedded(info) => {
+            let lines = (1 + info.offset)..=(lines + info.offset);
+            ScrapedSource { info, lines, code_html: code }.render_into(&mut writer).unwrap();
+        }
+    };
 }

src/librustdoc/html/sources.rs

@@ -59,6 +59,8 @@ nav.sub {
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);
 	--copy-path-img-hover-filter: invert(35%);
+	--code-example-button-color: #7f7f7f;
+	--code-example-button-hover-color: #595959;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);
@@ -162,6 +164,8 @@ nav.sub {
 		--copy-path-button-color: #999;
 		--copy-path-img-filter: invert(50%);
 		--copy-path-img-hover-filter: invert(65%);
+		--code-example-button-color: #7f7f7f;
+		--code-example-button-hover-color: #a5a5a5;
 		--codeblock-error-hover-color: rgb(255, 0, 0);
 		--codeblock-error-color: rgba(255, 0, 0, .5);
 		--codeblock-ignore-hover-color: rgb(255, 142, 0);

src/librustdoc/html/static/css/noscript.css

@@ -378,7 +378,7 @@ pre.item-decl {
 .src .content pre {
 	padding: 20px;
 }
-.rustdoc.src .example-wrap pre.src-line-numbers  {
+.rustdoc.src .example-wrap .src-line-numbers  {
 	padding: 20px 0 20px 4px;
 }
 
@@ -757,10 +757,32 @@ ul.block, .block li, .block ul {
 	margin-bottom: 10px;
 }
 
-.rustdoc .example-wrap > pre {
+.rustdoc .example-wrap > pre,
+.rustdoc .scraped-example .src-line-numbers,
+.rustdoc .scraped-example .src-line-numbers > pre {
 	border-radius: 6px;
 }
 
+/*
+If the code example line numbers are displayed, there will be a weird radius in the middle from
+both the code example and the line numbers, so we need to remove the radius in this case.
+*/
+.rustdoc .example-wrap > .example-line-numbers,
+.rustdoc .scraped-example .src-line-numbers,
+.rustdoc .scraped-example .src-line-numbers > pre {
+	border-top-right-radius: 0;
+	border-bottom-right-radius: 0;
+}
+.rustdoc .example-wrap > .example-line-numbers + pre,
+.rustdoc .scraped-example .rust {
+	border-top-left-radius: 0;
+	border-bottom-left-radius: 0;
+}
+
+.rustdoc .scraped-example {
+	position: relative;
+}
+
 /* For the last child of a div, the margin will be taken care of
 	by the margin-top of the next item. */
 .rustdoc .example-wrap:last-child {
@@ -772,23 +794,44 @@ ul.block, .block li, .block ul {
 	flex-grow: 1;
 }
 
-.rustdoc:not(.src) .example-wrap pre {
+.scraped-example:not(.expanded) .example-wrap {
+	/* scrape-examples.js has a constant DEFAULT_MAX_LINES (call it N) for the number
+	 * of lines shown in the un-expanded example code viewer. This pre needs to have
+	 * a max-height equal to line-height * N. The line-height is currently 1.5em,
+	 * and we include additional 10px for padding. */
+	max-height: calc(1.5em * 5 + 10px);
+}
+
+.rustdoc:not(.src) .scraped-example:not(.expanded) .src-line-numbers,
+.rustdoc:not(.src) .scraped-example:not(.expanded) .src-line-numbers > pre,
+.rustdoc:not(.src) .scraped-example:not(.expanded) pre.rust {
+	padding-bottom: 0;
+	/* See above comment, should be the same max-height. */
 	overflow: auto hidden;
 }
+.rustdoc:not(.src) .scraped-example .src-line-numbers {
+	padding-top: 0;
+}
+.rustdoc:not(.src) .scraped-example.expanded .src-line-numbers {
+	padding-bottom: 0;
+}
+
+.rustdoc:not(.src) .example-wrap pre {
+	overflow: auto;
+}
 
 .rustdoc .example-wrap pre.example-line-numbers,
-.rustdoc .example-wrap pre.src-line-numbers {
-	flex-grow: 0;
+.rustdoc .example-wrap .src-line-numbers {
 	min-width: fit-content; /* prevent collapsing into nothing in truncated scraped examples */
-	overflow: initial;
+	flex-grow: 0;
 	text-align: right;
 	-webkit-user-select: none;
 	user-select: none;
 	padding: 14px 8px;
 	color: var(--src-line-numbers-span-color);
 }
 
-.rustdoc .example-wrap pre.src-line-numbers {
+.rustdoc .scraped-example .src-line-numbers {
 	padding: 14px 0;
 }
 .src-line-numbers a, .src-line-numbers span {
@@ -1500,17 +1543,23 @@ instead, we check that it's not a "finger" cursor.
 .example-wrap .button-holder.keep-visible {
 	visibility: visible;
 }
-.example-wrap .button-holder .copy-button, .example-wrap .test-arrow {
+.example-wrap .button-holder > * {
 	background: var(--main-background-color);
 	cursor: pointer;
 	border-radius: var(--button-border-radius);
 	height: var(--copy-path-height);
 	width: var(--copy-path-width);
+	border: 0;
+	color: var(--code-example-button-color);
 }
-.example-wrap .button-holder .copy-button {
+.example-wrap .button-holder > *:hover {
+	color: var(--code-example-button-hover-color);
+}
+.example-wrap .button-holder > *:not(:first-child) {
 	margin-left: var(--button-left-margin);
+}
+.example-wrap .button-holder .copy-button {
 	padding: 2px 0 0 4px;
-	border: 0;
 }
 .example-wrap .button-holder .copy-button::before,
 .example-wrap .test-arrow::before {
@@ -2254,6 +2303,7 @@ in src-script.js and main.js
 	}
 }
 
+
 /* Should have min-width: (N + 1)px where N is the mobile breakpoint above. */
 @media (min-width: 701px) {
 	/* Places file-link for a scraped example on top of the example to save space.
@@ -2356,99 +2406,41 @@ in src-script.js and main.js
 	color: var(--scrape-example-help-hover-color);
 }
 
-.scraped-example {
-	/* So .scraped-example-title can be positioned absolutely */
-	position: relative;
-}
-
-.scraped-example .code-wrapper {
-	position: relative;
-	display: flex;
-	flex-direction: row;
-	flex-wrap: wrap;
-	width: 100%;
-}
-
-.scraped-example:not(.expanded) .code-wrapper {
-	/* scrape-examples.js has a constant DEFAULT_MAX_LINES (call it N) for the number
-	 * of lines shown in the un-expanded example code viewer. This pre needs to have
-	 * a max-height equal to line-height * N. The line-height is currently 1.5em,
-	 * and we include additional 10px for padding. */
-	 max-height: calc(1.5em * 5 + 10px);
-}
-
-.scraped-example:not(.expanded) .code-wrapper pre {
-	overflow-y: hidden;
-	padding-bottom: 0;
-	/* See above comment, should be the same max-height. */
-	max-height: calc(1.5em * 5 + 10px);
-}
-
-.more-scraped-examples .scraped-example:not(.expanded) .code-wrapper,
-.more-scraped-examples .scraped-example:not(.expanded) .code-wrapper pre {
-	/* See above comment, except this height is based on HIDDEN_MAX_LINES. */
-	max-height: calc(1.5em * 10 + 10px);
-}
-
-.scraped-example .code-wrapper .next,
-.scraped-example .code-wrapper .prev,
-.scraped-example .code-wrapper .expand {
-	color: var(--main-color);
-	position: absolute;
-	top: 0.25em;
-	z-index: 1;
-	padding: 0;
-	background: none;
-	border: none;
-	/* iOS button gradient: https://stackoverflow.com/q/5438567 */
-	-webkit-appearance: none;
-	opacity: 1;
-}
-.scraped-example .code-wrapper .prev {
-	right: 2.25em;
-}
-.scraped-example .code-wrapper .next {
-	right: 1.25em;
-}
-.scraped-example .code-wrapper .expand {
-	right: 0.25em;
-}
-
-.scraped-example:not(.expanded) .code-wrapper::before,
-.scraped-example:not(.expanded) .code-wrapper::after {
+.scraped-example:not(.expanded) .example-wrap::before,
+.scraped-example:not(.expanded) .example-wrap::after {
 	content: " ";
 	width: 100%;
 	height: 5px;
 	position: absolute;
 	z-index: 1;
 }
-.scraped-example:not(.expanded) .code-wrapper::before {
+.scraped-example:not(.expanded) .example-wrap::before {
 	top: 0;
 	background: linear-gradient(to bottom,
 		var(--scrape-example-code-wrapper-background-start),
 		var(--scrape-example-code-wrapper-background-end));
 }
-.scraped-example:not(.expanded) .code-wrapper::after {
+.scraped-example:not(.expanded) .example-wrap::after {
 	bottom: 0;
 	background: linear-gradient(to top,
 		var(--scrape-example-code-wrapper-background-start),
 		var(--scrape-example-code-wrapper-background-end));
 }
 
-.scraped-example .code-wrapper .example-wrap {
+.scraped-example:not(.expanded) {
 	width: 100%;
 	overflow-y: hidden;
 	margin-bottom: 0;
 }
 
-.scraped-example:not(.expanded) .code-wrapper .example-wrap {
+.scraped-example:not(.expanded) {
 	overflow-x: hidden;
 }
 
-.scraped-example .example-wrap .rust span.highlight {
+.scraped-example .rust span.highlight {
 	background: var(--scrape-example-code-line-highlight);
 }
-.scraped-example .example-wrap .rust span.highlight.focus {
+.scraped-example .rust span.highlight.focus {
 	background: var(--scrape-example-code-line-highlight-focus);
 }
 
@@ -2542,6 +2534,8 @@ by default.
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);
 	--copy-path-img-hover-filter: invert(35%);
+	--code-example-button-color: #7f7f7f;
+	--code-example-button-hover-color: #595959;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);
@@ -2644,6 +2638,8 @@ by default.
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);
 	--copy-path-img-hover-filter: invert(65%);
+	--code-example-button-color: #7f7f7f;
+	--code-example-button-hover-color: #a5a5a5;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);
@@ -2753,6 +2749,8 @@ Original by Dempfi (https://github.com/dempfi/ayu)
 	--copy-path-button-color: #fff;
 	--copy-path-img-filter: invert(70%);
 	--copy-path-img-hover-filter: invert(100%);
+	--code-example-button-color: #b2b2b2;
+	--code-example-button-hover-color: #fff;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);

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

@@ -1855,8 +1855,13 @@ href="https://doc.rust-lang.org/${channel}/rustdoc/read-documentation/search.htm
         // Since the button will be added, no need to keep this listener around.
         elem.removeEventListener("mouseover", addCopyButton);
 
-        const parent = document.createElement("div");
-        parent.className = "button-holder";
+        // If this is a scrapped example, there will already be a "button-holder" element.
+        let parent = elem.querySelector(".button-holder");
+        if (!parent) {
+            parent = document.createElement("div");
+            parent.className = "button-holder";
+        }
+
         const runButton = elem.querySelector(".test-arrow");
         if (runButton !== null) {
             // If there is a run button, we move it into the same div.

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

@@ -13,7 +13,7 @@
 
     // Scroll code block to the given code location
     function scrollToLoc(elt, loc, isHidden) {
-        const lines = elt.querySelector(".src-line-numbers");
+        const lines = elt.querySelector(".src-line-numbers > pre");
         let scrollOffset;
 
         // If the block is greater than the size of the viewer,
@@ -24,16 +24,15 @@
             const line = Math.max(0, loc[0] - 1);
             scrollOffset = lines.children[line].offsetTop;
         } else {
-            const wrapper = elt.querySelector(".code-wrapper");
-            const halfHeight = wrapper.offsetHeight / 2;
+            const halfHeight = elt.offsetHeight / 2;
             const offsetTop = lines.children[loc[0]].offsetTop;
             const lastLine = lines.children[loc[1]];
             const offsetBot = lastLine.offsetTop + lastLine.offsetHeight;
             const offsetMid = (offsetTop + offsetBot) / 2;
             scrollOffset = offsetMid - halfHeight;
         }
 
-        lines.scrollTo(0, scrollOffset);
+        lines.parentElement.scrollTo(0, scrollOffset);
         elt.querySelector(".rust").scrollTo(0, scrollOffset);
     }
 

src/librustdoc/html/static/js/scrape-examples.js

@@ -0,0 +1,33 @@
+<div class="scraped-example{% if !info.needs_expansion +%} expanded{% endif %}" data-locs="{{info.locations}}"> {# #}
+    <div class="scraped-example-title">
+       {{info.name +}} (<a href="{{info.url}}">{{info.title}}</a>) {# #}
+    </div>
+    <div class="example-wrap"> {# #}
+        {# https://developers.google.com/search/docs/crawling-indexing/robots-meta-tag#data-nosnippet-attr
+           Do not show "1 2 3 4 5 ..." in web search results. #}
+        <div class="src-line-numbers" data-nosnippet> {# #}
+            <pre>
+                {% for line in lines.clone() %}
+                    {# ~#}
+                    <span>{{line|safe}}</span>
+                {% endfor %}
+            </pre> {# #}
+        </div> {# #}
+        <pre class="rust"> {# #}
+            <code>
+                {{code_html|safe}}
+            </code> {# #}
+        </pre> {# #}
+        {% if info.needs_prev_next_buttons || info.needs_expansion %}
+            <div class="button-holder">
+                {% if info.needs_prev_next_buttons %}
+                    <button class="prev">&pr;</button> {# #}
+                    <button class="next">&sc;</button>
+                {% endif %}
+                {% if info.needs_expansion %}
+                    <button class="expand">&varr;</button>
+                {% endif %}
+            </div>
+        {% endif %}
+    </div> {# #}
+</div> {# #}

src/librustdoc/html/templates/scraped_source.html

@@ -1,21 +1,15 @@
-<div class="example-wrap"> {# #}
+<div class="example-wrap">
     {# https://developers.google.com/search/docs/crawling-indexing/robots-meta-tag#data-nosnippet-attr
        Do not show "1 2 3 4 5 ..." in web search results. #}
     <div data-nosnippet><pre class="src-line-numbers">
         {% for line in lines.clone() %}
-            {% if embedded %}
-                <span>{{line|safe}}</span>
-            {%~ else %}
-                <a href="#{{line|safe}}" id="{{line|safe}}">{{line|safe}}</a>
-            {%~ endif %}
+            {# ~#}
+            <a href="#{{line|safe}}" id="{{line|safe}}">{{line|safe}}</a>
         {% endfor %}
     </pre></div> {# #}
     <pre class="rust"> {# #}
         <code>
-            {% if needs_expansion %}
-                <button class="expand">&varr;</button>
-            {% endif %}
             {{code_html|safe}}
         </code> {# #}
     </pre> {# #}
-</div>
+</div> {# #}

src/librustdoc/html/templates/source.html

@@ -0,0 +1,7 @@
+use crate::command::Command;
+use crate::env_var;
+
+/// Returns a command that can be used to invoke Cargo.
+pub fn cargo() -> Command {
+    Command::new(env_var("BOOTSTRAP_CARGO"))
+}

src/tools/run-make-support/src/external_deps/cargo.rs

@@ -2,6 +2,7 @@
 //! such as `cc` or `python`.
 
 pub mod c_build;
+pub mod cargo;
 pub mod cc;
 pub mod clang;
 pub mod htmldocck;

src/tools/run-make-support/src/external_deps/mod.rs

@@ -36,10 +36,13 @@ pub struct Rustc {
 
 crate::macros::impl_common_helpers!(Rustc);
 
+pub fn rustc_path() -> String {
+    env_var("RUSTC")
+}
+
 #[track_caller]
 fn setup_common() -> Command {
-    let rustc = env_var("RUSTC");
-    let mut cmd = Command::new(rustc);
+    let mut cmd = Command::new(rustc_path());
     set_host_rpath(&mut cmd);
     cmd
 }

src/tools/run-make-support/src/external_deps/rustc.rs

@@ -48,6 +48,7 @@ pub use external_deps::{c_build, cc, clang, htmldocck, llvm, python, rustc, rust
 // These rely on external dependencies.
 pub use cc::{cc, cxx, extra_c_flags, extra_cxx_flags, Cc};
 pub use c_build::{build_native_dynamic_lib, build_native_static_lib, build_native_static_lib_optimized, build_native_static_lib_cxx};
+pub use cargo::cargo;
 pub use clang::{clang, Clang};
 pub use htmldocck::htmldocck;
 pub use llvm::{
@@ -56,7 +57,7 @@ pub use llvm::{
     LlvmProfdata, LlvmReadobj,
 };
 pub use python::python_command;
-pub use rustc::{aux_build, bare_rustc, rustc, Rustc};
+pub use rustc::{aux_build, bare_rustc, rustc, rustc_path, Rustc};
 pub use rustdoc::{bare_rustdoc, rustdoc, Rustdoc};
 
 /// [`diff`][mod@diff] is implemented in terms of the [similar] library.
@@ -96,3 +97,4 @@ pub use assertion_helpers::{
 pub use string::{
     count_regex_matches_in_files_with_extension, invalid_utf8_contains, invalid_utf8_not_contains,
 };
+use crate::external_deps::cargo;

src/tools/run-make-support/src/lib.rs

@@ -242,7 +242,7 @@ const PERMITTED_DEPS_LOCATION: &str = concat!(file!(), ":", line!());
 /// rustc. Please check with the compiler team before adding an entry.
 const PERMITTED_RUSTC_DEPENDENCIES: &[&str] = &[
     // tidy-alphabetical-start
-    "adler",
+    "adler2",
     "ahash",
     "aho-corasick",
     "allocator-api2", // FIXME: only appears in Cargo.lock due to https://github.com/rust-lang/cargo/issues/10801
@@ -481,6 +481,7 @@ const PERMITTED_STDLIB_DEPENDENCIES: &[&str] = &[
     "rand_core",
     "rand_xorshift",
     "rustc-demangle",
+    "shlex",
     "unicode-width",
     "unwinding",
     "wasi",

src/tools/rustbook/Cargo.lock

@@ -0,0 +1,22 @@
+// Make sure we do not request sanitizers for naked functions.
+
+//@ only-x86_64
+//@ needs-sanitizer-address
+//@ compile-flags: -Zsanitizer=address
+
+#![crate_type = "lib"]
+#![no_std]
+#![feature(abi_x86_interrupt, naked_functions)]
+
+// CHECK: define x86_intrcc void @page_fault_handler(ptr {{.*}}%0, i64 {{.*}}%1){{.*}}#[[ATTRS:[0-9]+]] {
+// CHECK-NOT: memcpy
+#[naked]
+#[no_mangle]
+pub extern "x86-interrupt" fn page_fault_handler(_: u64, _: u64) {
+    unsafe {
+        core::arch::asm!("ud2", options(noreturn));
+    }
+}
+
+// CHECK: #[[ATTRS]] =
+// CHECK-NOT: sanitize_address

src/tools/tidy/src/deps.rs

@@ -0,0 +1,36 @@
+//! Checks if selected rustc crates can be compiled on the stable channel (or a "simulation" of it).
+//! These crates are designed to be used by downstream users.
+
+use run_make_support::{cargo, rustc_path, source_root};
+
+fn main() {
+    // Use the stage0 beta cargo for the compilation (it shouldn't really matter which cargo we use)
+    cargo()
+        // Ensure `proc-macro2`'s nightly detection is disabled
+        .env("RUSTC_STAGE", "0")
+        .env("RUSTC", rustc_path())
+        // We want to disallow all nightly features to simulate a stable build
+        .env("RUSTFLAGS", "-Zallow-features=")
+        .arg("build")
+        .arg("--manifest-path")
+        .arg(source_root().join("Cargo.toml"))
+        .args(&[
+            // Avoid depending on transitive rustc crates
+            "--no-default-features",
+            // Emit artifacts in this temporary directory, not in the source_root's `target` folder
+            "--target-dir",
+            "target",
+        ])
+        // Check that these crates can be compiled on "stable"
+        .args(&[
+            "-p",
+            "rustc_type_ir",
+            "-p",
+            "rustc_next_trait_solver",
+            "-p",
+            "rustc_pattern_analysis",
+            "-p",
+            "rustc_lexer",
+        ])
+        .run();
+}

tests/codegen/naked-asan.rs

@@ -94,3 +94,24 @@ call-function: ("check-buttons",{
     "filter": "invert(0.5)",
     "filter_hover": "invert(0.35)",
 })
+
+define-function: (
+    "check-buttons-position",
+    [pre_selector],
+    block {
+        move-cursor-to: |pre_selector| + " .rust:not(.item-decl)"
+        store-position: (|pre_selector| + " .rust:not(.item-decl)", {"x": x, "y": y})
+        assert-position: (|pre_selector| + " .rust:not(.item-decl) + .button-holder", {
+            "y": |y| + 4,
+        })
+    }
+)
+
+call-function: ("check-buttons-position", {"pre_selector": ".example-wrap"})
+
+go-to: "file://" + |DOC_PATH| + "/scrape_examples/fn.test_many.html"
+// We should work as well for scraped examples.
+call-function: ("check-buttons-position", {"pre_selector": ".scraped-example .example-wrap"})
+// And also when the scraped example "title" goes above.
+set-window-size: (600, 600)
+call-function: ("check-buttons-position", {"pre_selector": ".scraped-example .example-wrap"})

tests/run-make/rustc-crates-on-stable/rmake.rs

@@ -5,6 +5,18 @@ go-to: "file://" + |DOC_PATH| + "/test_docs/fn.foo.html"
 // We check that without this setting, there is no line number displayed.
 assert-false: "pre.example-line-numbers"
 
+// All corners should be rounded.
+assert-css: (
+    ".example-wrap .rust",
+    {
+        "border-top-left-radius": "6px",
+        "border-bottom-left-radius": "6px",
+        "border-top-right-radius": "6px",
+        "border-bottom-right-radius": "6px",
+    },
+    ALL,
+)
+
 // We set the setting to show the line numbers on code examples.
 set-local-storage: {"rustdoc-line-numbers": "true"}
 reload:
@@ -29,9 +41,21 @@ define-function: (
                 "margin": "0px",
                 "padding": "14px 8px",
                 "text-align": "right",
+                // There should not be a radius on the right of the line numbers.
+                "border-top-left-radius": "6px",
+                "border-bottom-left-radius": "6px",
+                "border-top-right-radius": "0px",
+                "border-bottom-right-radius": "0px",
             },
             ALL,
         )
+        // There should not be a radius on the left of the line numbers.
+        assert-css: ("pre.example-line-numbers + .rust", {
+            "border-top-left-radius": "0px",
+            "border-bottom-left-radius": "0px",
+            "border-top-right-radius": "6px",
+            "border-bottom-right-radius": "6px",
+        })
     },
 )
 call-function: ("check-colors", {
@@ -64,7 +88,56 @@ wait-for: 100 // wait-for-false does not exist
 assert-false: "pre.example-line-numbers"
 assert-local-storage: {"rustdoc-line-numbers": "false" }
 
+// Check that the rounded corners are back.
+assert-css: (
+    ".example-wrap .rust",
+    {
+        "border-top-left-radius": "6px",
+        "border-bottom-left-radius": "6px",
+        "border-top-right-radius": "6px",
+        "border-bottom-right-radius": "6px",
+    },
+    ALL,
+)
+
 // Finally, turn it on again.
 click: "input#line-numbers"
 wait-for: "pre.example-line-numbers"
 assert-local-storage: {"rustdoc-line-numbers": "true" }
+
+// Same check with scraped examples line numbers.
+go-to: "file://" + |DOC_PATH| + "/scrape_examples/fn.test_many.html"
+
+assert-css: (
+    ".scraped-example .src-line-numbers > pre",
+    {
+        // There should not be a radius on the right of the line numbers.
+        "border-top-left-radius": "6px",
+        "border-bottom-left-radius": "6px",
+        "border-top-right-radius": "0px",
+        "border-bottom-right-radius": "0px",
+    },
+    ALL,
+)
+assert-css: (
+    ".scraped-example .src-line-numbers",
+    {
+        // There should not be a radius on the right of the line numbers.
+        "border-top-left-radius": "6px",
+        "border-bottom-left-radius": "6px",
+        "border-top-right-radius": "0px",
+        "border-bottom-right-radius": "0px",
+    },
+    ALL,
+)
+assert-css: (
+    ".scraped-example .rust",
+    {
+        // There should not be a radius on the left of the code.
+        "border-top-left-radius": "0px",
+        "border-bottom-left-radius": "0px",
+        "border-top-right-radius": "6px",
+        "border-bottom-right-radius": "6px",
+    },
+    ALL,
+)

tests/rustdoc-gui/code-example-buttons.goml

@@ -3,29 +3,53 @@
 go-to: "file://" + |DOC_PATH| + "/scrape_examples/fn.test.html"
 
 // The next/prev buttons vertically scroll the code viewport between examples
-store-property: (".scraped-example-list > .scraped-example pre", {"scrollTop": initialScrollTop})
+move-cursor-to: ".scraped-example-list > .scraped-example"
+store-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "scrollTop": initialScrollTop,
+})
+assert-property: (".scraped-example-list > .scraped-example .rust", {
+    "scrollTop": |initialScrollTop|,
+})
 focus: ".scraped-example-list > .scraped-example .next"
 press-key: "Enter"
-assert-property-false: (".scraped-example-list > .scraped-example pre", {
+assert-property-false: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "scrollTop": |initialScrollTop|
+}, NEAR)
+assert-property-false: (".scraped-example-list > .scraped-example .rust", {
     "scrollTop": |initialScrollTop|
 }, NEAR)
 focus: ".scraped-example-list > .scraped-example .prev"
 press-key: "Enter"
-assert-property: (".scraped-example-list > .scraped-example pre", {
+assert-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "scrollTop": |initialScrollTop|
+}, NEAR)
+assert-property: (".scraped-example-list > .scraped-example .rust", {
     "scrollTop": |initialScrollTop|
 }, NEAR)
 
 // The expand button increases the scrollHeight of the minimized code viewport
 store-property: (".scraped-example-list > .scraped-example pre", {"offsetHeight": smallOffsetHeight})
-assert-property-false: (".scraped-example-list > .scraped-example pre", {
+assert-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "scrollHeight": |smallOffsetHeight|
+}, NEAR)
+assert-property: (".scraped-example-list > .scraped-example .rust", {
     "scrollHeight": |smallOffsetHeight|
 }, NEAR)
 focus: ".scraped-example-list > .scraped-example .expand"
 press-key: "Enter"
-assert-property-false: (".scraped-example-list > .scraped-example pre", {
+assert-property-false: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "offsetHeight": |smallOffsetHeight|
+}, NEAR)
+assert-property-false: (".scraped-example-list > .scraped-example .rust", {
     "offsetHeight": |smallOffsetHeight|
 }, NEAR)
-store-property: (".scraped-example-list > .scraped-example pre", {"offsetHeight": fullOffsetHeight})
-assert-property: (".scraped-example-list > .scraped-example pre", {
+store-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "offsetHeight": fullOffsetHeight,
+})
+assert-property: (".scraped-example-list > .scraped-example .rust", {
+    "offsetHeight": |fullOffsetHeight|,
+    "scrollHeight": |fullOffsetHeight|,
+})
+assert-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
     "scrollHeight": |fullOffsetHeight|
 }, NEAR)

tests/rustdoc-gui/docblock-code-block-line-number.goml

@@ -10,10 +10,10 @@ define-function: (
     block {
         call-function: ("switch-theme", {"theme": |theme|})
         wait-for: ".more-examples-toggle"
-        assert-css: (".scraped-example .example-wrap .rust span.highlight:not(.focus)", {
+        assert-css: (".scraped-example .rust span.highlight:not(.focus)", {
             "background-color": |highlight|,
         }, ALL)
-        assert-css: (".scraped-example .example-wrap .rust span.highlight.focus", {
+        assert-css: (".scraped-example .rust span.highlight.focus", {
             "background-color": |highlight_focus|,
         }, ALL)
 
@@ -67,11 +67,11 @@ define-function: (
     [theme, background_color_start, background_color_end],
     block {
         call-function: ("switch-theme", {"theme": |theme|})
-        assert-css: (".scraped-example:not(.expanded) .code-wrapper::before", {
+        assert-css: (".scraped-example:not(.expanded) .example-wrap::before", {
             "background-image": "linear-gradient(" + |background_color_start| + ", " +
                 |background_color_end| + ")",
         })
-        assert-css: (".scraped-example:not(.expanded) .code-wrapper::after", {
+        assert-css: (".scraped-example:not(.expanded) .example-wrap::after", {
             "background-image": "linear-gradient(to top, " + |background_color_start| + ", " +
                 |background_color_end| + ")",
         })

tests/rustdoc-gui/scrape-examples-button-focus.goml

@@ -1,48 +1,115 @@
 // Check that the line number column has the correct layout.
 go-to: "file://" + |DOC_PATH| + "/scrape_examples/fn.test_many.html"
 
+set-window-size: (1000, 1000)
+
 // Check that it's not zero.
 assert-property-false: (
-    ".more-scraped-examples .scraped-example .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example .src-line-numbers",
     {"clientWidth": "0"}
 )
 
 // Check that examples with very long lines have the same width as ones that don't.
 store-property: (
-    ".more-scraped-examples .scraped-example:nth-child(2) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(2) .src-line-numbers",
     {"clientWidth": clientWidth},
 )
 
 assert-property: (
-    ".more-scraped-examples .scraped-example:nth-child(3) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(3) .src-line-numbers",
     {"clientWidth": |clientWidth|}
 )
 
 assert-property: (
-    ".more-scraped-examples .scraped-example:nth-child(4) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(4) .src-line-numbers",
     {"clientWidth": |clientWidth|}
 )
 
 assert-property: (
-    ".more-scraped-examples .scraped-example:nth-child(5) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(5) .src-line-numbers",
     {"clientWidth": |clientWidth|}
 )
 
 assert-property: (
-    ".more-scraped-examples .scraped-example:nth-child(6) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(6) .src-line-numbers",
     {"clientWidth": |clientWidth|}
 )
 
+// The "title" should be located at the right bottom corner of the code example.
+store-position: (".scraped-example .example-wrap", {"x": x, "y": y})
+store-size: (".scraped-example .example-wrap", {"width": width, "height": height})
+store-size: (".scraped-example .scraped-example-title", {
+    "width": title_width,
+    "height": title_height,
+})
+assert-position: (".scraped-example .scraped-example-title", {
+    "x": |x| + |width| - |title_width| - 5,
+    "y": |y| + |height| - |title_height| - 8,
+})
+
+// Check that the expand button works and also that line number aligns with code.
+move-cursor-to: ".scraped-example .rust"
+click: ".scraped-example .button-holder .expand"
+wait-for: ".scraped-example.expanded"
+// They should have the same y position.
+compare-elements-position: (
+    ".scraped-example.expanded .src-line-numbers pre span",
+    ".scraped-example.expanded .rust code",
+    ["y"],
+)
+// And they should have the same height.
+compare-elements-size: (
+    ".scraped-example.expanded .src-line-numbers",
+    ".scraped-example.expanded .rust",
+    ["height"],
+)
+// Collapse code again.
+click: ".scraped-example .button-holder .expand"
+
 // Check that for both mobile and desktop sizes, the buttons in scraped examples are displayed
 // correctly.
 
 store-value: (offset_y, 4)
 
 // First with desktop
-assert-position: (".scraped-example .code-wrapper", {"y": 226})
-assert-position: (".scraped-example .code-wrapper .prev", {"y": 226 + |offset_y|})
+assert-position: (".scraped-example", {"y": 226})
+assert-position: (".scraped-example .prev", {"y": 226 + |offset_y|})
+
+// Gradient background should be at the top of the code block.
+assert-css: (".scraped-example .example-wrap::before", {"top": "0px"})
+assert-css: (".scraped-example .example-wrap::after", {"bottom": "0px"})
 
 // Then with mobile
 set-window-size: (600, 600)
-assert-position: (".scraped-example .code-wrapper", {"y": 308})
-assert-position: (".scraped-example .code-wrapper .prev", {"y": 308 + |offset_y|})
+store-size: (".scraped-example .scraped-example-title", {"height": title_height})
+assert-position: (".scraped-example", {"y": 284})
+assert-position: (".scraped-example .prev", {"y": 284 + |offset_y| + |title_height|})
+
+define-function: (
+    "check_title_and_code_position",
+    [],
+    block {
+        // Title should be above the code.
+        store-position: (".scraped-example .example-wrap .src-line-numbers", {"x": x, "y": y})
+        store-size: (".scraped-example .scraped-example-title", { "height": title_height })
+
+        assert-position: (".scraped-example .scraped-example-title", {
+            "x": |x|, // same X position.
+            "y": |y| - |title_height|,
+        })
+
+        // Line numbers should be right beside the code.
+        compare-elements-position: (
+            ".scraped-example .example-wrap .src-line-numbers",
+            ".scraped-example .example-wrap .rust",
+            ["y"],
+        )
+    }
+)
+
+// Check that the title is now above the code.
+call-function: ("check_title_and_code_position", {})
+
+// Then with small mobile
+set-window-size: (300, 300)
+call-function: ("check_title_and_code_position", {})

tests/rustdoc-gui/scrape-examples-color.goml

@@ -23,6 +23,8 @@
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);
 	--copy-path-img-hover-filter: invert(35%);
+        --code-example-button-color: #7f7f7f;
+	--code-example-button-hover-color: #a5a5a5;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);