Auto merge of rust-lang#84644 - JohnTitor:rollup-nzq9rjz, r=JohnTitor

Rollup of 5 pull requests

Successful merges:

 - rust-lang#84529 (Improve coverage spans for chained function calls)
 - rust-lang#84616 (Fix empty dom toggle)
 - rust-lang#84622 (Make traits with GATs not object safe)
 - rust-lang#84624 (Make sentence in env::args_os' docs plain and simple)
 - rust-lang#84642 (Stabilize vec_extend_from_within)

Failed merges:

 - rust-lang#84636 (rustdoc: change aliases attribute to data-aliases)

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

compiler/rustc_middle/src/traits/mod.rs

@@ -670,6 +670,9 @@ pub enum ObjectSafetyViolation {
 
     /// Associated const.
     AssocConst(Symbol, Span),
+
+    /// GAT
+    GAT(Symbol, Span),
 }
 
 impl ObjectSafetyViolation {
@@ -715,6 +718,9 @@ impl ObjectSafetyViolation {
                 format!("it contains associated `const` `{}`", name).into()
             }
             ObjectSafetyViolation::AssocConst(..) => "it contains this associated `const`".into(),
+            ObjectSafetyViolation::GAT(name, _) => {
+                format!("it contains the generic associated type `{}`", name).into()
+            }
         }
     }
 
@@ -773,6 +779,7 @@ impl ObjectSafetyViolation {
                 );
             }
             ObjectSafetyViolation::AssocConst(name, _)
+            | ObjectSafetyViolation::GAT(name, _)
             | ObjectSafetyViolation::Method(name, ..) => {
                 err.help(&format!("consider moving `{}` to another trait", name));
             }
@@ -786,6 +793,7 @@ impl ObjectSafetyViolation {
             ObjectSafetyViolation::SupertraitSelf(spans)
             | ObjectSafetyViolation::SizedSelf(spans) => spans.clone(),
             ObjectSafetyViolation::AssocConst(_, span)
+            | ObjectSafetyViolation::GAT(_, span)
             | ObjectSafetyViolation::Method(_, _, span)
                 if *span != DUMMY_SP =>
             {

compiler/rustc_mir/src/transform/coverage/spans.rs

@@ -717,11 +717,21 @@ pub(super) fn filtered_terminator_span(
         | TerminatorKind::FalseEdge { .. }
         | TerminatorKind::Goto { .. } => None,
 
+        // Call `func` operand can have a more specific span when part of a chain of calls
+        | TerminatorKind::Call { ref func, .. } => {
+            let mut span = terminator.source_info.span;
+            if let mir::Operand::Constant(box constant) = func {
+                if constant.span.lo() > span.lo() {
+                    span = span.with_lo(constant.span.lo());
+                }
+            }
+            Some(function_source_span(span, body_span))
+        }
+
         // Retain spans from all other terminators
         TerminatorKind::Resume
         | TerminatorKind::Abort
         | TerminatorKind::Return
-        | TerminatorKind::Call { .. }
         | TerminatorKind::Yield { .. }
         | TerminatorKind::GeneratorDrop
         | TerminatorKind::FalseUnwind { .. }

compiler/rustc_trait_selection/src/traits/object_safety.rs

@@ -132,6 +132,14 @@ fn object_safety_violations_for_trait(
             .map(|item| ObjectSafetyViolation::AssocConst(item.ident.name, item.ident.span)),
     );
 
+    violations.extend(
+        tcx.associated_items(trait_def_id)
+            .in_definition_order()
+            .filter(|item| item.kind == ty::AssocKind::Type)
+            .filter(|item| !tcx.generics_of(item.def_id).params.is_empty())
+            .map(|item| ObjectSafetyViolation::GAT(item.ident.name, item.ident.span)),
+    );
+
     debug!(
         "object_safety_violations_for_trait(trait_def_id={:?}) = {:?}",
         trait_def_id, violations

compiler/rustc_trait_selection/src/traits/select/confirmation.rs

@@ -462,12 +462,11 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
         for assoc_type in assoc_types {
             if !tcx.generics_of(assoc_type).params.is_empty() {
-                // FIXME(generic_associated_types) generate placeholders to
-                // extend the trait substs.
-                tcx.sess.span_fatal(
+                tcx.sess.delay_span_bug(
                     obligation.cause.span,
-                    "generic associated types in trait objects are not supported yet",
+                    "GATs in trait object shouldn't have been considered",
                 );
+                return Err(SelectionError::Unimplemented);
             }
             // This maybe belongs in wf, but that can't (doesn't) handle
             // higher-ranked things.

library/alloc/src/lib.rs

@@ -76,7 +76,6 @@
 #![cfg_attr(test, feature(test))]
 #![cfg_attr(test, feature(new_uninit))]
 #![feature(allocator_api)]
-#![feature(vec_extend_from_within)]
 #![feature(array_chunks)]
 #![feature(array_methods)]
 #![feature(array_windows)]

library/alloc/src/vec/mod.rs

@@ -2124,8 +2124,6 @@ impl<T: Clone, A: Allocator> Vec<T, A> {
     /// ## Examples
     ///
     /// ```
-    /// #![feature(vec_extend_from_within)]
-    ///
     /// let mut vec = vec![0, 1, 2, 3, 4];
     ///
     /// vec.extend_from_within(2..);
@@ -2137,7 +2135,7 @@ impl<T: Clone, A: Allocator> Vec<T, A> {
     /// vec.extend_from_within(4..8);
     /// assert_eq!(vec, [0, 1, 2, 3, 4, 2, 3, 4, 0, 1, 4, 2, 3, 4]);
     /// ```
-    #[unstable(feature = "vec_extend_from_within", issue = "81656")]
+    #[stable(feature = "vec_extend_from_within", since = "1.53.0")]
     pub fn extend_from_within<R>(&mut self, src: R)
     where
         R: RangeBounds<usize>,

library/alloc/tests/lib.rs

@@ -20,7 +20,6 @@
 #![feature(vecdeque_binary_search)]
 #![feature(slice_group_by)]
 #![feature(slice_partition_dedup)]
-#![feature(vec_extend_from_within)]
 #![feature(vec_spare_capacity)]
 #![feature(string_remove_matches)]
 

library/std/src/env.rs

@@ -752,7 +752,7 @@ pub fn args() -> Args {
 /// does on macOS and Windows.
 ///
 /// Note that the returned iterator will not check if the arguments to the
-/// process are valid Unicode. To ensure UTF-8 validity,
+/// process are valid Unicode. If you want to panic on invalid UTF-8,
 /// use the [`args`] function instead.
 ///
 /// # Examples

src/librustdoc/html/format.rs

@@ -82,6 +82,10 @@ impl Buffer {
         self.buffer.push_str(s);
     }
 
+    crate fn push_buffer(&mut self, other: Buffer) {
+        self.buffer.push_str(&other.buffer);
+    }
+
     // Intended for consumption by write! and writeln! (std::fmt) but without
     // the fmt::Result return type imposed by fmt::Write (and avoiding the trait
     // import).

src/librustdoc/html/render/mod.rs

@@ -1281,99 +1281,6 @@ fn render_impl(
     let trait_ = i.trait_did_full(cache).map(|did| &traits[&did]);
     let mut close_tags = String::new();
 
-    if render_mode == RenderMode::Normal {
-        let id = cx.derive_id(match i.inner_impl().trait_ {
-            Some(ref t) => {
-                if is_on_foreign_type {
-                    get_id_for_impl_on_foreign_type(&i.inner_impl().for_, t, cx)
-                } else {
-                    format!("impl-{}", small_url_encode(format!("{:#}", t.print(cx))))
-                }
-            }
-            None => "impl".to_string(),
-        });
-        let aliases = if aliases.is_empty() {
-            String::new()
-        } else {
-            format!(" aliases=\"{}\"", aliases.join(","))
-        };
-        if let Some(use_absolute) = use_absolute {
-            write!(
-                w,
-                "<details class=\"rustdoc-toggle implementors-toggle\" open>\
-                     <summary>\
-                         <h3 id=\"{}\" class=\"impl\"{}>\
-                             <code class=\"in-band\">",
-                id, aliases
-            );
-            close_tags.insert_str(0, "</details>");
-            write!(w, "{}", i.inner_impl().print(use_absolute, cx));
-            if show_def_docs {
-                for it in &i.inner_impl().items {
-                    if let clean::TypedefItem(ref tydef, _) = *it.kind {
-                        w.write_str("<span class=\"where fmt-newline\">  ");
-                        assoc_type(
-                            w,
-                            it,
-                            &[],
-                            Some(&tydef.type_),
-                            AssocItemLink::Anchor(None),
-                            "",
-                            cx,
-                        );
-                        w.write_str(";</span>");
-                    }
-                }
-            }
-            w.write_str("</code>");
-        } else {
-            write!(
-                w,
-                "<details class=\"rustdoc-toggle implementors-toggle\" open>\
-                     <summary>\
-                         <h3 id=\"{}\" class=\"impl\"{}>\
-                             <code class=\"in-band\">{}</code>",
-                id,
-                aliases,
-                i.inner_impl().print(false, cx)
-            );
-            close_tags.insert_str(0, "</details>");
-        }
-        write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
-        render_stability_since_raw(
-            w,
-            i.impl_item.stable_since(tcx).as_deref(),
-            i.impl_item.const_stable_since(tcx).as_deref(),
-            outer_version,
-            outer_const_version,
-        );
-        write_srclink(cx, &i.impl_item, w);
-        w.write_str("</h3></summary>");
-
-        if trait_.is_some() {
-            if let Some(portability) = portability(&i.impl_item, Some(parent)) {
-                write!(w, "<div class=\"item-info\">{}</div>", portability);
-            }
-        }
-
-        if let Some(ref dox) = cx.shared.maybe_collapsed_doc_value(&i.impl_item) {
-            let mut ids = cx.id_map.borrow_mut();
-            write!(
-                w,
-                "<div class=\"docblock\">{}</div>",
-                Markdown(
-                    &*dox,
-                    &i.impl_item.links(cx),
-                    &mut ids,
-                    cx.shared.codes,
-                    cx.shared.edition(),
-                    &cx.shared.playground
-                )
-                .into_string()
-            );
-        }
-    }
-
     fn doc_impl_item(
         w: &mut Buffer,
         cx: &Context<'_>,
@@ -1549,11 +1456,10 @@ fn render_impl(
         }
     }
 
-    w.write_str("<div class=\"impl-items\">");
-    close_tags.insert_str(0, "</div>");
+    let mut impl_items = Buffer::empty_from(w);
     for trait_item in &i.inner_impl().items {
         doc_impl_item(
-            w,
+            &mut impl_items,
             cx,
             trait_item,
             if trait_.is_some() { &i.impl_item } else { parent },
@@ -1609,7 +1515,7 @@ fn render_impl(
     if show_default_items {
         if let Some(t) = trait_ {
             render_default_items(
-                w,
+                &mut impl_items,
                 cx,
                 &t.trait_,
                 &i.inner_impl(),
@@ -1621,6 +1527,111 @@ fn render_impl(
             );
         }
     }
+    let details_str = if impl_items.is_empty() {
+        ""
+    } else {
+        "<details class=\"rustdoc-toggle implementors-toggle\" open><summary>"
+    };
+    if render_mode == RenderMode::Normal {
+        let id = cx.derive_id(match i.inner_impl().trait_ {
+            Some(ref t) => {
+                if is_on_foreign_type {
+                    get_id_for_impl_on_foreign_type(&i.inner_impl().for_, t, cx)
+                } else {
+                    format!("impl-{}", small_url_encode(format!("{:#}", t.print(cx))))
+                }
+            }
+            None => "impl".to_string(),
+        });
+        let aliases = if aliases.is_empty() {
+            String::new()
+        } else {
+            format!(" aliases=\"{}\"", aliases.join(","))
+        };
+        if let Some(use_absolute) = use_absolute {
+            write!(
+                w,
+                "{}<h3 id=\"{}\" class=\"impl\"{}><code class=\"in-band\">",
+                details_str, id, aliases
+            );
+            if !impl_items.is_empty() {
+                close_tags.insert_str(0, "</details>");
+            }
+            write!(w, "{}", i.inner_impl().print(use_absolute, cx));
+            if show_def_docs {
+                for it in &i.inner_impl().items {
+                    if let clean::TypedefItem(ref tydef, _) = *it.kind {
+                        w.write_str("<span class=\"where fmt-newline\">  ");
+                        assoc_type(
+                            w,
+                            it,
+                            &[],
+                            Some(&tydef.type_),
+                            AssocItemLink::Anchor(None),
+                            "",
+                            cx,
+                        );
+                        w.write_str(";</span>");
+                    }
+                }
+            }
+            w.write_str("</code>");
+        } else {
+            write!(
+                w,
+                "{}<h3 id=\"{}\" class=\"impl\"{}><code class=\"in-band\">{}</code>",
+                details_str,
+                id,
+                aliases,
+                i.inner_impl().print(false, cx)
+            );
+            if !impl_items.is_empty() {
+                close_tags.insert_str(0, "</details>");
+            }
+        }
+        write!(w, "<a href=\"#{}\" class=\"anchor\"></a>", id);
+        render_stability_since_raw(
+            w,
+            i.impl_item.stable_since(tcx).as_deref(),
+            i.impl_item.const_stable_since(tcx).as_deref(),
+            outer_version,
+            outer_const_version,
+        );
+        write_srclink(cx, &i.impl_item, w);
+        if impl_items.is_empty() {
+            w.write_str("</h3>");
+        } else {
+            w.write_str("</h3></summary>");
+        }
+
+        if trait_.is_some() {
+            if let Some(portability) = portability(&i.impl_item, Some(parent)) {
+                write!(w, "<div class=\"item-info\">{}</div>", portability);
+            }
+        }
+
+        if let Some(ref dox) = cx.shared.maybe_collapsed_doc_value(&i.impl_item) {
+            let mut ids = cx.id_map.borrow_mut();
+            write!(
+                w,
+                "<div class=\"docblock\">{}</div>",
+                Markdown(
+                    &*dox,
+                    &i.impl_item.links(cx),
+                    &mut ids,
+                    cx.shared.codes,
+                    cx.shared.edition(),
+                    &cx.shared.playground
+                )
+                .into_string()
+            );
+        }
+    }
+    if !impl_items.is_empty() {
+        w.write_str("<div class=\"impl-items\">");
+        w.push_buffer(impl_items);
+        close_tags.insert_str(0, "</div>");
+    }
     w.write_str(&close_tags);
 }