Auto merge of #147151 - Zalathar:rollup-w81rn0j, r=Zalathar

bors · bors · commit 21a13b8864a7 · 2025-09-29T11:52:07.000Z
Rollup of 5 pull requests Successful merges: - #146653 (improve diagnostics for empty attributes) - #146987 (impl Ord for params and use unstable sort) - #147101 (Use `Iterator::eq` and (dogfood) `eq_by` in compiler and library ) - #147123 (Fix removed version numbers of `doc_auto_cfg` and `doc_cfg_hide`) - #147149 (add joboet to library review rotation) r? `@ghost` `@rustbot` modify labels: rollup
diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
@@ -114,8 +114,7 @@ impl PartialEq<Symbol> for Path {
 impl PartialEq<&[Symbol]> for Path {
     #[inline]
     fn eq(&self, names: &&[Symbol]) -> bool {
-        self.segments.len() == names.len()
-            && self.segments.iter().zip(names.iter()).all(|(s1, s2)| s1 == s2)
+        self.segments.iter().eq(*names)
     }
 }
 
diff --git a/compiler/rustc_ast/src/lib.rs b/compiler/rustc_ast/src/lib.rs
@@ -15,6 +15,7 @@
 #![feature(associated_type_defaults)]
 #![feature(box_patterns)]
 #![feature(if_let_guard)]
+#![feature(iter_order_by)]
 #![feature(macro_metavar_expr)]
 #![feature(rustdoc_internals)]
 #![recursion_limit = "256"]
diff --git a/compiler/rustc_ast/src/tokenstream.rs b/compiler/rustc_ast/src/tokenstream.rs
@@ -48,9 +48,7 @@ impl TokenTree {
         match (self, other) {
             (TokenTree::Token(token, _), TokenTree::Token(token2, _)) => token.kind == token2.kind,
             (TokenTree::Delimited(.., delim, tts), TokenTree::Delimited(.., delim2, tts2)) => {
-                delim == delim2
-                    && tts.len() == tts2.len()
-                    && tts.iter().zip(tts2.iter()).all(|(a, b)| a.eq_unspanned(b))
+                delim == delim2 && tts.iter().eq_by(tts2.iter(), |a, b| a.eq_unspanned(b))
             }
             _ => false,
         }
diff --git a/compiler/rustc_attr_parsing/messages.ftl b/compiler/rustc_attr_parsing/messages.ftl
@@ -8,7 +8,15 @@ attr_parsing_deprecated_item_suggestion =
 
 attr_parsing_empty_attribute =
     unused attribute
-    .suggestion = remove this attribute
+    .suggestion = {$valid_without_list ->
+        [true] remove these parentheses
+        *[other] remove this attribute
+    }
+    .note = {$valid_without_list ->
+        [true] using `{$attr_path}` with an empty list is equivalent to not using a list at all
+        *[other] using `{$attr_path}` with an empty list has no effect
+    }
+
 
 attr_parsing_invalid_target = `#[{$name}]` attribute cannot be used on {$target}
     .help = `#[{$name}]` can {$only}be applied to {$applied}
diff --git a/compiler/rustc_attr_parsing/src/context.rs b/compiler/rustc_attr_parsing/src/context.rs
@@ -597,7 +597,12 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
     }
 
     pub(crate) fn warn_empty_attribute(&mut self, span: Span) {
-        self.emit_lint(AttributeLintKind::EmptyAttribute { first_span: span }, span);
+        let attr_path = self.attr_path.clone();
+        let valid_without_list = self.template.word;
+        self.emit_lint(
+            AttributeLintKind::EmptyAttribute { first_span: span, attr_path, valid_without_list },
+            span,
+        );
     }
 }
 
diff --git a/compiler/rustc_attr_parsing/src/lints.rs b/compiler/rustc_attr_parsing/src/lints.rs
@@ -43,12 +43,18 @@ pub fn emit_attribute_lint<L: LintEmitter>(lint: &AttributeLint<L::Id>, lint_emi
                     ),
                 },
             ),
-        AttributeLintKind::EmptyAttribute { first_span } => lint_emitter.emit_node_span_lint(
-            rustc_session::lint::builtin::UNUSED_ATTRIBUTES,
-            *id,
-            *first_span,
-            session_diagnostics::EmptyAttributeList { attr_span: *first_span },
-        ),
+        AttributeLintKind::EmptyAttribute { first_span, attr_path, valid_without_list } => {
+            lint_emitter.emit_node_span_lint(
+                rustc_session::lint::builtin::UNUSED_ATTRIBUTES,
+                *id,
+                *first_span,
+                session_diagnostics::EmptyAttributeList {
+                    attr_span: *first_span,
+                    attr_path: attr_path.clone(),
+                    valid_without_list: *valid_without_list,
+                },
+            )
+        }
         AttributeLintKind::InvalidTarget { name, target, applied, only } => lint_emitter
             .emit_node_span_lint(
                 // This check is here because `deprecated` had its own lint group and removing this would be a breaking change
diff --git a/compiler/rustc_attr_parsing/src/parser.rs b/compiler/rustc_attr_parsing/src/parser.rs
@@ -49,7 +49,7 @@ impl<'a> PathParser<'a> {
     }
 
     pub fn segments_is(&self, segments: &[Symbol]) -> bool {
-        self.len() == segments.len() && self.segments().zip(segments).all(|(a, b)| a.name == *b)
+        self.segments().map(|segment| &segment.name).eq(segments)
     }
 
     pub fn word(&self) -> Option<Ident> {
diff --git a/compiler/rustc_attr_parsing/src/session_diagnostics.rs b/compiler/rustc_attr_parsing/src/session_diagnostics.rs
@@ -503,9 +503,12 @@ pub(crate) struct EmptyConfusables {
 
 #[derive(LintDiagnostic)]
 #[diag(attr_parsing_empty_attribute)]
+#[note]
 pub(crate) struct EmptyAttributeList {
     #[suggestion(code = "", applicability = "machine-applicable")]
     pub attr_span: Span,
+    pub attr_path: AttrPath,
+    pub valid_without_list: bool,
 }
 
 #[derive(LintDiagnostic)]
diff --git a/compiler/rustc_builtin_macros/src/autodiff.rs b/compiler/rustc_builtin_macros/src/autodiff.rs
@@ -377,8 +377,7 @@ mod llvm_enzyme {
                 (ast::AttrKind::Normal(a), ast::AttrKind::Normal(b)) => {
                     let a = &a.item.path;
                     let b = &b.item.path;
-                    a.segments.len() == b.segments.len()
-                        && a.segments.iter().zip(b.segments.iter()).all(|(a, b)| a.ident == b.ident)
+                    a.segments.iter().eq_by(&b.segments, |a, b| a.ident == b.ident)
                 }
                 _ => false,
             }
diff --git a/compiler/rustc_builtin_macros/src/deriving/coerce_pointee.rs b/compiler/rustc_builtin_macros/src/deriving/coerce_pointee.rs
@@ -356,21 +356,14 @@ fn contains_maybe_sized_bound(bounds: &[GenericBound]) -> bool {
     bounds.iter().any(is_maybe_sized_bound)
 }
 
-fn path_segment_is_exact_match(path_segments: &[ast::PathSegment], syms: &[Symbol]) -> bool {
-    path_segments.iter().zip(syms).all(|(segment, &symbol)| segment.ident.name == symbol)
-}
-
 fn is_sized_marker(path: &ast::Path) -> bool {
     const CORE_UNSIZE: [Symbol; 3] = [sym::core, sym::marker, sym::Sized];
     const STD_UNSIZE: [Symbol; 3] = [sym::std, sym::marker, sym::Sized];
-    if path.segments.len() == 4 && path.is_global() {
-        path_segment_is_exact_match(&path.segments[1..], &CORE_UNSIZE)
-            || path_segment_is_exact_match(&path.segments[1..], &STD_UNSIZE)
-    } else if path.segments.len() == 3 {
-        path_segment_is_exact_match(&path.segments, &CORE_UNSIZE)
-            || path_segment_is_exact_match(&path.segments, &STD_UNSIZE)
+    let segments = || path.segments.iter().map(|segment| segment.ident.name);
+    if path.is_global() {
+        segments().skip(1).eq(CORE_UNSIZE) || segments().skip(1).eq(STD_UNSIZE)
     } else {
-        *path == sym::Sized
+        segments().eq(CORE_UNSIZE) || segments().eq(STD_UNSIZE) || *path == sym::Sized
     }
 }
 
diff --git a/compiler/rustc_builtin_macros/src/format.rs b/compiler/rustc_builtin_macros/src/format.rs
@@ -768,7 +768,7 @@ fn report_missing_placeholders(
 
     if !found_foreign && invalid_refs.is_empty() {
         // Show example if user didn't use any format specifiers
-        let show_example = used.iter().all(|used| !used);
+        let show_example = !used.contains(&true);
 
         if !show_example {
             if unused.len() > 1 {
diff --git a/compiler/rustc_builtin_macros/src/lib.rs b/compiler/rustc_builtin_macros/src/lib.rs
@@ -11,6 +11,7 @@
 #![feature(box_patterns)]
 #![feature(decl_macro)]
 #![feature(if_let_guard)]
+#![feature(iter_order_by)]
 #![feature(proc_macro_internals)]
 #![feature(proc_macro_quote)]
 #![feature(rustdoc_internals)]
diff --git a/compiler/rustc_feature/src/removed.rs b/compiler/rustc_feature/src/removed.rs
@@ -102,9 +102,9 @@ declare_features! (
     /// Allows deriving traits as per `SmartPointer` specification
     (removed, derive_smart_pointer, "1.84.0", Some(123430), Some("replaced by `CoercePointee`"), 131284),
     /// Tells rustdoc to automatically generate `#[doc(cfg(...))]`.
-    (removed, doc_auto_cfg, "1.58.0", Some(43781), Some("merged into `doc_cfg`"), 138907),
+    (removed, doc_auto_cfg, "CURRENT_RUSTC_VERSION", Some(43781), Some("merged into `doc_cfg`"), 138907),
     /// Allows `#[doc(cfg_hide(...))]`.
-    (removed, doc_cfg_hide, "1.57.0", Some(43781), Some("merged into `doc_cfg`"), 138907),
+    (removed, doc_cfg_hide, "CURRENT_RUSTC_VERSION", Some(43781), Some("merged into `doc_cfg`"), 138907),
     /// Allows using `#[doc(keyword = "...")]`.
     (removed, doc_keyword, "1.58.0", Some(51315),
      Some("merged into `#![feature(rustdoc_internals)]`"), 90420),
diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
@@ -1298,10 +1298,7 @@ impl AttributeExt for Attribute {
     #[inline]
     fn path_matches(&self, name: &[Symbol]) -> bool {
         match &self {
-            Attribute::Unparsed(n) => {
-                n.path.segments.len() == name.len()
-                    && n.path.segments.iter().zip(name).all(|(s, n)| s.name == *n)
-            }
+            Attribute::Unparsed(n) => n.path.segments.iter().map(|ident| &ident.name).eq(name),
             _ => false,
         }
     }
diff --git a/compiler/rustc_hir/src/lints.rs b/compiler/rustc_hir/src/lints.rs
@@ -31,6 +31,12 @@ pub struct AttributeLint<Id> {
 
 #[derive(Clone, Debug, HashStable_Generic)]
 pub enum AttributeLintKind {
+    /// Copy of `IllFormedAttributeInput`
+    /// specifically for the `invalid_macro_export_arguments` lint until that is removed,
+    /// see <https://github.com/rust-lang/rust/pull/143857#issuecomment-3079175663>
+    InvalidMacroExportArguments {
+        suggestions: Vec<String>,
+    },
     UnusedDuplicate {
         this: Span,
         other: Span,
@@ -41,13 +47,8 @@ pub enum AttributeLintKind {
     },
     EmptyAttribute {
         first_span: Span,
-    },
-
-    /// Copy of `IllFormedAttributeInput`
-    /// specifically for the `invalid_macro_export_arguments` lint until that is removed,
-    /// see <https://github.com/rust-lang/rust/pull/143857#issuecomment-3079175663>
-    InvalidMacroExportArguments {
-        suggestions: Vec<String>,
+        attr_path: AttrPath,
+        valid_without_list: bool,
     },
     InvalidTarget {
         name: AttrPath,
diff --git a/compiler/rustc_hir_analysis/src/constrained_generic_params.rs b/compiler/rustc_hir_analysis/src/constrained_generic_params.rs
@@ -4,7 +4,7 @@ use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeSuperVisitable, TypeV
 use rustc_span::Span;
 use tracing::debug;
 
-#[derive(Clone, PartialEq, Eq, Hash, Debug)]
+#[derive(Clone, Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub(crate) struct Parameter(pub u32);
 
 impl From<ty::ParamTy> for Parameter {
diff --git a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
@@ -275,7 +275,7 @@ fn check_duplicate_params<'tcx>(
     span: Span,
 ) -> Result<(), ErrorGuaranteed> {
     let mut base_params = cgp::parameters_for(tcx, parent_args, true);
-    base_params.sort_by_key(|param| param.0);
+    base_params.sort_unstable();
     if let (_, [duplicate, ..]) = base_params.partition_dedup() {
         let param = impl1_args[duplicate.0 as usize];
         return Err(tcx
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
@@ -2803,9 +2803,7 @@ impl<'a, 'b, 'tcx> ArgMatchingCtxt<'a, 'b, 'tcx> {
         if let Some((assoc, fn_sig)) = self.similar_assoc(call_name)
             && fn_sig.inputs()[1..]
                 .iter()
-                .zip(input_types.iter())
-                .all(|(expected, found)| self.may_coerce(*expected, *found))
-            && fn_sig.inputs()[1..].len() == input_types.len()
+                .eq_by(input_types, |expected, found| self.may_coerce(*expected, found))
         {
             let assoc_name = assoc.name();
             err.span_suggestion_verbose(
diff --git a/compiler/rustc_hir_typeck/src/lib.rs b/compiler/rustc_hir_typeck/src/lib.rs
@@ -5,6 +5,7 @@
 #![feature(box_patterns)]
 #![feature(if_let_guard)]
 #![feature(iter_intersperse)]
+#![feature(iter_order_by)]
 #![feature(never_type)]
 // tidy-alphabetical-end
 
diff --git a/compiler/rustc_hir_typeck/src/method/suggest.rs b/compiler/rustc_hir_typeck/src/method/suggest.rs
@@ -1914,9 +1914,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         if let Some(ref args) = call_args
                             && fn_sig.inputs()[1..]
                                 .iter()
-                                .zip(args.into_iter())
-                                .all(|(expected, found)| self.may_coerce(*expected, *found))
-                            && fn_sig.inputs()[1..].len() == args.len()
+                                .eq_by(args, |expected, found| self.may_coerce(*expected, *found))
                         {
                             err.span_suggestion_verbose(
                                 item_name.span,
diff --git a/compiler/rustc_parse/src/lib.rs b/compiler/rustc_parse/src/lib.rs
@@ -9,6 +9,7 @@
 #![feature(default_field_values)]
 #![feature(if_let_guard)]
 #![feature(iter_intersperse)]
+#![feature(iter_order_by)]
 #![recursion_limit = "256"]
 // tidy-alphabetical-end
 
diff --git a/compiler/rustc_parse/src/parser/tokenstream/tests.rs b/compiler/rustc_parse/src/parser/tokenstream/tests.rs
@@ -15,7 +15,7 @@ fn sp(a: u32, b: u32) -> Span {
 }
 
 fn cmp_token_stream(a: &TokenStream, b: &TokenStream) -> bool {
-    a.len() == b.len() && a.iter().zip(b.iter()).all(|(x, y)| x.eq_unspanned(y))
+    a.iter().eq_by(b.iter(), |x, y| x.eq_unspanned(y))
 }
 
 #[test]
diff --git a/library/alloc/src/collections/btree/map.rs b/library/alloc/src/collections/btree/map.rs
@@ -2413,7 +2413,7 @@ impl<K, V> Default for BTreeMap<K, V> {
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<K: PartialEq, V: PartialEq, A: Allocator + Clone> PartialEq for BTreeMap<K, V, A> {
     fn eq(&self, other: &BTreeMap<K, V, A>) -> bool {
-        self.len() == other.len() && self.iter().zip(other).all(|(a, b)| a == b)
+        self.iter().eq(other)
     }
 }
 
diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs
@@ -1685,7 +1685,7 @@ impl Type {
         match (self_cleared, other_cleared) {
             // Recursive cases.
             (Type::Tuple(a), Type::Tuple(b)) => {
-                a.len() == b.len() && a.iter().zip(b).all(|(a, b)| a.is_doc_subtype_of(b, cache))
+                a.iter().eq_by(b, |a, b| a.is_doc_subtype_of(b, cache))
             }
             (Type::Slice(a), Type::Slice(b)) => a.is_doc_subtype_of(b, cache),
             (Type::Array(a, al), Type::Array(b, bl)) => al == bl && a.is_doc_subtype_of(b, cache),
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
@@ -13,6 +13,7 @@
 #![feature(if_let_guard)]
 #![feature(iter_advance_by)]
 #![feature(iter_intersperse)]
+#![feature(iter_order_by)]
 #![feature(rustc_private)]
 #![feature(test)]
 #![warn(rustc::internal)]
diff --git a/tests/ui/attributes/empty-repr.stderr b/tests/ui/attributes/empty-repr.stderr
@@ -4,6 +4,7 @@ error: unused attribute
 LL | #[repr()]
    | ^^^^^^^^^ help: remove this attribute
    |
+   = note: using `repr` with an empty list has no effect
 note: the lint level is defined here
   --> $DIR/empty-repr.rs:4:9
    |
diff --git a/tests/ui/empty/empty-attributes.stderr b/tests/ui/empty/empty-attributes.stderr
@@ -56,12 +56,16 @@ error: unused attribute
    |
 LL | #[repr()]
    | ^^^^^^^^^ help: remove this attribute
+   |
+   = note: using `repr` with an empty list has no effect
 
 error: unused attribute
   --> $DIR/empty-attributes.rs:12:1
    |
 LL | #[target_feature()]
    | ^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = note: using `target_feature` with an empty list has no effect
 
 error: aborting due to 8 previous errors
 
diff --git a/tests/ui/macros/macro-use-all-and-none.stderr b/tests/ui/macros/macro-use-all-and-none.stderr
@@ -2,8 +2,9 @@ warning: unused attribute
   --> $DIR/macro-use-all-and-none.rs:7:12
    |
 LL | #[macro_use()]
-   |            ^^ help: remove this attribute
+   |            ^^ help: remove these parentheses
    |
+   = note: using `macro_use` with an empty list is equivalent to not using a list at all
 note: the lint level is defined here
   --> $DIR/macro-use-all-and-none.rs:4:9
    |
diff --git a/tests/ui/repr/repr-empty-packed.stderr b/tests/ui/repr/repr-empty-packed.stderr
@@ -15,6 +15,7 @@ error: unused attribute
 LL | #[repr()]
    | ^^^^^^^^^ help: remove this attribute
    |
+   = note: using `repr` with an empty list has no effect
 note: the lint level is defined here
   --> $DIR/repr-empty-packed.rs:2:9
    |
diff --git a/triagebot.toml b/triagebot.toml
@@ -1382,6 +1382,7 @@ libs = [
     "@tgross35",
     "@thomcc",
     "@ibraheemdev",
+    "@joboet",
 ]
 infra-ci = [
     "@Mark-Simulacrum",

Original file line number	Diff line number	Diff line change
`@@ -114,8 +114,7 @@ impl PartialEq<Symbol> for Path {`
`114`	`114`	`impl PartialEq<&[Symbol]> for Path {`
`115`	`115`	`#[inline]`
`116`	`116`	`fn eq(&self, names: &&[Symbol]) -> bool {`
`117`		`- self.segments.len() == names.len()`
`118`		`- && self.segments.iter().zip(names.iter()).all(\|(s1, s2)\| s1 == s2)`
	`117`	`+ self.segments.iter().eq(*names)`
`119`	`118`	`}`
`120`	`119`	`}`
`121`	`120`
Original file line number	Diff line number	Diff line change
`@@ -48,9 +48,7 @@ impl TokenTree {`
`48`	`48`	`match (self, other) {`
`49`	`49`	`(TokenTree::Token(token, _), TokenTree::Token(token2, _)) => token.kind == token2.kind,`
`50`	`50`	`(TokenTree::Delimited(.., delim, tts), TokenTree::Delimited(.., delim2, tts2)) => {`
`51`		`- delim == delim2`
`52`		`- && tts.len() == tts2.len()`
`53`		`- && tts.iter().zip(tts2.iter()).all(\|(a, b)\| a.eq_unspanned(b))`
	`51`	`+ delim == delim2 && tts.iter().eq_by(tts2.iter(), \|a, b\| a.eq_unspanned(b))`
`54`	`52`	`}`
`55`	`53`	`_ => false,`
`56`	`54`	`}`
Original file line number	Diff line number	Diff line change
`@@ -597,7 +597,12 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {`
`597`	`597`	`}`
`598`	`598`
`599`	`599`	`pub(crate) fn warn_empty_attribute(&mut self, span: Span) {`
`600`		`- self.emit_lint(AttributeLintKind::EmptyAttribute { first_span: span }, span);`
	`600`	`+ let attr_path = self.attr_path.clone();`
	`601`	`+ let valid_without_list = self.template.word;`
	`602`	`+ self.emit_lint(`
	`603`	`+ AttributeLintKind::EmptyAttribute { first_span: span, attr_path, valid_without_list },`
	`604`	`+ span,`
	`605`	`+ );`
`601`	`606`	`}`
`602`	`607`	`}`
`603`	`608`
Original file line number	Diff line number	Diff line change
`@@ -49,7 +49,7 @@ impl<'a> PathParser<'a> {`
`49`	`49`	`}`
`50`	`50`
`51`	`51`	`pub fn segments_is(&self, segments: &[Symbol]) -> bool {`
`52`		`- self.len() == segments.len() && self.segments().zip(segments).all(\|(a, b)\| a.name == *b)`
	`52`	`+ self.segments().map(\|segment\| &segment.name).eq(segments)`
`53`	`53`	`}`
`54`	`54`
`55`	`55`	`pub fn word(&self) -> Option<Ident> {`
Original file line number	Diff line number	Diff line change
`@@ -377,8 +377,7 @@ mod llvm_enzyme {`
`377`	`377`	`(ast::AttrKind::Normal(a), ast::AttrKind::Normal(b)) => {`
`378`	`378`	`let a = &a.item.path;`
`379`	`379`	`let b = &b.item.path;`
`380`		`- a.segments.len() == b.segments.len()`
`381`		`- && a.segments.iter().zip(b.segments.iter()).all(\|(a, b)\| a.ident == b.ident)`
	`380`	`+ a.segments.iter().eq_by(&b.segments, \|a, b\| a.ident == b.ident)`
`382`	`381`	`}`
`383`	`382`	`_ => false,`
`384`	`383`	`}`