Clippy subtree update

src/bootstrap/src/core/build_steps/clippy.rs

@@ -19,6 +19,7 @@ const IGNORED_RULES_FOR_STD_AND_RUSTC: &[&str] = &[
     "too_many_arguments",
     "needless_lifetimes", // people want to keep the lifetimes
     "wrong_self_convention",
+    "approx_constant", // libcore is what defines those
 ];
 
 fn lint_args(builder: &Builder<'_>, config: &LintConfig, ignored_rules: &[&str]) -> Vec<String> {

src/tools/clippy/.github/workflows/feature_freeze.yml

@@ -20,16 +20,26 @@ jobs:
     # of the pull request, as malicious code would be able to access the private
     # GitHub token.
     steps:
-    - name: Check PR Changes
-      id: pr-changes
-      run: echo "::set-output name=changes::${{ toJson(github.event.pull_request.changed_files) }}"
-
-    - name: Create Comment
-      if: steps.pr-changes.outputs.changes != '[]'
-      run: |
-        # Use GitHub API to create a comment on the PR
-        PR_NUMBER=${{ github.event.pull_request.number }}
-        COMMENT="**Seems that you are trying to add a new lint!**\nWe are currently in a [feature freeze](https://doc.rust-lang.org/nightly/clippy/development/feature_freeze.html), so we are delaying all lint-adding PRs to September 18 and focusing on bugfixes.\nThanks a lot for your contribution, and sorry for the inconvenience.\nWith ❤ from the Clippy team\n\n@rustbot note Feature-freeze\n@rustbot blocked\n@rustbot label +A-lint\n"
-        GITHUB_TOKEN=${{ secrets.GITHUB_TOKEN }}
-        COMMENT_URL="https://api.github.com/repos/${{ github.repository }}/issues/${PR_NUMBER}/comments"
-        curl -s -H "Authorization: token ${GITHUB_TOKEN}" -X POST $COMMENT_URL -d "{\"body\":\"$COMMENT\"}"
+      - name: Add freeze warning comment
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GITHUB_REPOSITORY: ${{ github.repository }}
+          PR_NUMBER: ${{ github.event.pull_request.number }}
+        run: |
+          COMMENT=$(echo "**Seems that you are trying to add a new lint!**\n\
+          \n\
+          We are currently in a [feature freeze](https://doc.rust-lang.org/nightly/clippy/development/feature_freeze.html), so we are delaying all lint-adding PRs to September 18 and [focusing on bugfixes](https://github.com/rust-lang/rust-clippy/issues/15086).\n\
+          \n\
+          Thanks a lot for your contribution, and sorry for the inconvenience.\n\
+          \n\
+          With ❤ from the Clippy team.\n\
+          \n\
+          @rustbot note Feature-freeze\n\
+          @rustbot blocked\n\
+          @rustbot label +A-lint"
+          )
+          curl -s -H "Authorization: Bearer $GITHUB_TOKEN" \
+             -H "Content-Type: application/vnd.github.raw+json" \
+             -X POST \
+             --data "{\"body\":\"${COMMENT}\"}" \
+             "https://api.github.com/repos/${GITHUB_REPOSITORY}/issues/${PR_NUMBER}/comments"

src/tools/clippy/.gitignore

@@ -19,8 +19,10 @@ out
 
 # Generated by Cargo
 *Cargo.lock
+!/clippy_test_deps/Cargo.lock
 /target
 /clippy_lints/target
+/clippy_lints_internal/target
 /clippy_utils/target
 /clippy_dev/target
 /lintcheck/target

src/tools/clippy/clippy_dev/src/fmt.rs

@@ -3,7 +3,7 @@ use crate::utils::{
     walk_dir_no_dot_or_target,
 };
 use itertools::Itertools;
-use rustc_lexer::{TokenKind, tokenize};
+use rustc_lexer::{FrontmatterAllowed, TokenKind, tokenize};
 use std::fmt::Write;
 use std::fs;
 use std::io::{self, Read};
@@ -92,7 +92,7 @@ fn fmt_conf(check: bool) -> Result<(), Error> {
     let mut fields = Vec::new();
     let mut state = State::Start;
 
-    for (i, t) in tokenize(conf)
+    for (i, t) in tokenize(conf, FrontmatterAllowed::No)
         .map(|x| {
             let start = pos;
             pos += x.len;

src/tools/clippy/clippy_lints/src/approx_const.rs

@@ -92,9 +92,11 @@ impl LateLintPass<'_> for ApproxConstant {
 impl ApproxConstant {
     fn check_known_consts(&self, cx: &LateContext<'_>, span: Span, s: symbol::Symbol, module: &str) {
         let s = s.as_str();
-        if s.parse::<f64>().is_ok() {
+        if let Ok(maybe_constant) = s.parse::<f64>() {
             for &(constant, name, min_digits, msrv) in &KNOWN_CONSTS {
-                if is_approx_const(constant, s, min_digits) && msrv.is_none_or(|msrv| self.msrv.meets(cx, msrv)) {
+                if is_approx_const(constant, s, maybe_constant, min_digits)
+                    && msrv.is_none_or(|msrv| self.msrv.meets(cx, msrv))
+                {
                     span_lint_and_help(
                         cx,
                         APPROX_CONSTANT,
@@ -112,18 +114,35 @@ impl ApproxConstant {
 
 impl_lint_pass!(ApproxConstant => [APPROX_CONSTANT]);
 
+fn count_digits_after_dot(input: &str) -> usize {
+    input
+        .char_indices()
+        .find(|(_, ch)| *ch == '.')
+        .map_or(0, |(i, _)| input.len() - i - 1)
+}
+
 /// Returns `false` if the number of significant figures in `value` are
 /// less than `min_digits`; otherwise, returns true if `value` is equal
-/// to `constant`, rounded to the number of digits present in `value`.
+/// to `constant`, rounded to the number of significant digits present in `value`.
 #[must_use]
-fn is_approx_const(constant: f64, value: &str, min_digits: usize) -> bool {
+fn is_approx_const(constant: f64, value: &str, f_value: f64, min_digits: usize) -> bool {
     if value.len() <= min_digits {
+        // The value is not precise enough
         false
-    } else if constant.to_string().starts_with(value) {
-        // The value is a truncated constant
+    } else if f_value.to_string().len() > min_digits && constant.to_string().starts_with(&f_value.to_string()) {
+        // The value represents the same value
         true
     } else {
-        let round_const = format!("{constant:.*}", value.len() - 2);
+        // The value is a truncated constant
+
+        // Print constant with numeric formatting (`0`), with the length of `value` as minimum width
+        // (`value_len$`), and with the same precision as `value` (`.value_prec$`).
+        // See https://doc.rust-lang.org/std/fmt/index.html.
+        let round_const = format!(
+            "{constant:0value_len$.value_prec$}",
+            value_len = value.len(),
+            value_prec = count_digits_after_dot(value)
+        );
         value == round_const
     }
 }

src/tools/clippy/clippy_lints/src/arbitrary_source_item_ordering.rs

@@ -8,11 +8,11 @@ use clippy_utils::diagnostics::span_lint_and_note;
 use clippy_utils::is_cfg_test;
 use rustc_attr_data_structures::AttributeKind;
 use rustc_hir::{
-    Attribute, FieldDef, HirId, IsAuto, ImplItemId, Item, ItemKind, Mod, OwnerId, QPath, TraitItemId, TyKind,
-    Variant, VariantData,
+    Attribute, FieldDef, HirId, ImplItemId, IsAuto, Item, ItemKind, Mod, OwnerId, QPath, TraitItemId, TyKind, Variant,
+    VariantData,
 };
-use rustc_middle::ty::AssocKind;
 use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_middle::ty::AssocKind;
 use rustc_session::impl_lint_pass;
 use rustc_span::Ident;
 
@@ -469,13 +469,14 @@ impl<'tcx> LateLintPass<'tcx> for ArbitrarySourceItemOrdering {
 /// This is implemented here because `rustc_hir` is not a dependency of
 /// `clippy_config`.
 fn convert_assoc_item_kind(cx: &LateContext<'_>, owner_id: OwnerId) -> SourceItemOrderingTraitAssocItemKind {
-    let kind = cx.tcx.associated_item(owner_id.def_id).kind;
-
     #[allow(clippy::enum_glob_use)] // Very local glob use for legibility.
     use SourceItemOrderingTraitAssocItemKind::*;
+
+    let kind = cx.tcx.associated_item(owner_id.def_id).kind;
+
     match kind {
-        AssocKind::Const{..} => Const,
-        AssocKind::Type {..}=> Type,
+        AssocKind::Const { .. } => Const,
+        AssocKind::Type { .. } => Type,
         AssocKind::Fn { .. } => Fn,
     }
 }

src/tools/clippy/clippy_lints/src/arc_with_non_send_sync.rs

@@ -73,7 +73,7 @@ impl<'tcx> LateLintPass<'tcx> for ArcWithNonSendSync {
                         diag.note(format!(
                             "`Arc<{arg_ty}>` is not `Send` and `Sync` as `{arg_ty}` is {reason}"
                         ));
-                        diag.help("if the `Arc` will not used be across threads replace it with an `Rc`");
+                        diag.help("if the `Arc` will not be used across threads replace it with an `Rc`");
                         diag.help(format!(
                             "otherwise make `{arg_ty}` `Send` and `Sync` or consider a wrapper type such as `Mutex`"
                         ));

src/tools/clippy/clippy_lints/src/attrs/useless_attribute.rs

@@ -36,6 +36,7 @@ pub(super) fn check(cx: &EarlyContext<'_>, item: &Item, attrs: &[Attribute]) {
                                     | sym::unused_braces
                                     | sym::unused_import_braces
                                     | sym::unused_imports
+                                    | sym::redundant_imports
                             )
                         {
                             return;

src/tools/clippy/clippy_lints/src/casts/confusing_method_to_numeric_cast.rs

@@ -59,9 +59,8 @@ fn get_const_name_and_ty_name(
 
 pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>, cast_from: Ty<'_>, cast_to: Ty<'_>) {
     // We allow casts from any function type to any function type.
-    match cast_to.kind() {
-        ty::FnDef(..) | ty::FnPtr(..) => return,
-        _ => { /* continue to checks */ },
+    if cast_to.is_fn() {
+        return;
     }
 
     if let ty::FnDef(def_id, generics) = cast_from.kind()

src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast.rs

@@ -3,7 +3,7 @@ use clippy_utils::source::snippet_with_applicability;
 use rustc_errors::Applicability;
 use rustc_hir::Expr;
 use rustc_lint::LateContext;
-use rustc_middle::ty::{self, Ty};
+use rustc_middle::ty::Ty;
 
 use super::{FN_TO_NUMERIC_CAST, utils};
 
@@ -13,23 +13,20 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>,
         return;
     };
 
-    match cast_from.kind() {
-        ty::FnDef(..) | ty::FnPtr(..) => {
-            let mut applicability = Applicability::MaybeIncorrect;
+    if cast_from.is_fn() {
+        let mut applicability = Applicability::MaybeIncorrect;
 
-            if to_nbits >= cx.tcx.data_layout.pointer_size().bits() && !cast_to.is_usize() {
-                let from_snippet = snippet_with_applicability(cx, cast_expr.span, "x", &mut applicability);
-                span_lint_and_sugg(
-                    cx,
-                    FN_TO_NUMERIC_CAST,
-                    expr.span,
-                    format!("casting function pointer `{from_snippet}` to `{cast_to}`"),
-                    "try",
-                    format!("{from_snippet} as usize"),
-                    applicability,
-                );
-            }
-        },
-        _ => {},
+        if to_nbits >= cx.tcx.data_layout.pointer_size().bits() && !cast_to.is_usize() {
+            let from_snippet = snippet_with_applicability(cx, cast_expr.span, "x", &mut applicability);
+            span_lint_and_sugg(
+                cx,
+                FN_TO_NUMERIC_CAST,
+                expr.span,
+                format!("casting function pointer `{from_snippet}` to `{cast_to}`"),
+                "try",
+                format!("{from_snippet} as usize"),
+                applicability,
+            );
+        }
     }
 }

src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast_any.rs

@@ -3,18 +3,17 @@ use clippy_utils::source::snippet_with_applicability;
 use rustc_errors::Applicability;
 use rustc_hir::Expr;
 use rustc_lint::LateContext;
-use rustc_middle::ty::{self, Ty};
+use rustc_middle::ty::Ty;
 
 use super::FN_TO_NUMERIC_CAST_ANY;
 
 pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>, cast_from: Ty<'_>, cast_to: Ty<'_>) {
     // We allow casts from any function type to any function type.
-    match cast_to.kind() {
-        ty::FnDef(..) | ty::FnPtr(..) => return,
-        _ => { /* continue to checks */ },
+    if cast_to.is_fn() {
+        return;
     }
 
-    if let ty::FnDef(..) | ty::FnPtr(..) = cast_from.kind() {
+    if cast_from.is_fn() {
         let mut applicability = Applicability::MaybeIncorrect;
         let from_snippet = snippet_with_applicability(cx, cast_expr.span, "..", &mut applicability);
 

src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast_with_truncation.rs

@@ -3,7 +3,7 @@ use clippy_utils::source::snippet_with_applicability;
 use rustc_errors::Applicability;
 use rustc_hir::Expr;
 use rustc_lint::LateContext;
-use rustc_middle::ty::{self, Ty};
+use rustc_middle::ty::Ty;
 
 use super::{FN_TO_NUMERIC_CAST_WITH_TRUNCATION, utils};
 
@@ -12,23 +12,20 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>,
     let Some(to_nbits) = utils::int_ty_to_nbits(cx.tcx, cast_to) else {
         return;
     };
-    match cast_from.kind() {
-        ty::FnDef(..) | ty::FnPtr(..) => {
-            let mut applicability = Applicability::MaybeIncorrect;
-            let from_snippet = snippet_with_applicability(cx, cast_expr.span, "x", &mut applicability);
+    if cast_from.is_fn() {
+        let mut applicability = Applicability::MaybeIncorrect;
+        let from_snippet = snippet_with_applicability(cx, cast_expr.span, "x", &mut applicability);
 
-            if to_nbits < cx.tcx.data_layout.pointer_size().bits() {
-                span_lint_and_sugg(
-                    cx,
-                    FN_TO_NUMERIC_CAST_WITH_TRUNCATION,
-                    expr.span,
-                    format!("casting function pointer `{from_snippet}` to `{cast_to}`, which truncates the value"),
-                    "try",
-                    format!("{from_snippet} as usize"),
-                    applicability,
-                );
-            }
-        },
-        _ => {},
+        if to_nbits < cx.tcx.data_layout.pointer_size().bits() {
+            span_lint_and_sugg(
+                cx,
+                FN_TO_NUMERIC_CAST_WITH_TRUNCATION,
+                expr.span,
+                format!("casting function pointer `{from_snippet}` to `{cast_to}`, which truncates the value"),
+                "try",
+                format!("{from_snippet} as usize"),
+                applicability,
+            );
+        }
     }
 }

src/tools/clippy/clippy_lints/src/casts/ptr_as_ptr.rs

@@ -4,10 +4,9 @@ use clippy_utils::source::snippet_with_applicability;
 use clippy_utils::sugg::Sugg;
 use rustc_errors::Applicability;
 use rustc_hir::{Expr, ExprKind, Mutability, QPath, TyKind};
-use rustc_hir_pretty::qpath_to_string;
 use rustc_lint::LateContext;
 use rustc_middle::ty;
-use rustc_span::sym;
+use rustc_span::{Span, sym};
 
 use super::PTR_AS_PTR;
 
@@ -74,7 +73,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, msrv: Msrv) {
 
         let (help, final_suggestion) = if let Some(method) = omit_cast.corresponding_item() {
             // don't force absolute path
-            let method = qpath_to_string(&cx.tcx, method);
+            let method = snippet_with_applicability(cx, qpath_span_without_turbofish(method), "..", &mut app);
             ("try call directly", format!("{method}{turbofish}()"))
         } else {
             let cast_expr_sugg = Sugg::hir_with_applicability(cx, cast_expr, "_", &mut app);
@@ -96,3 +95,14 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, msrv: Msrv) {
         );
     }
 }
+
+fn qpath_span_without_turbofish(qpath: &QPath<'_>) -> Span {
+    if let QPath::Resolved(_, path) = qpath
+        && let [.., last_ident] = path.segments
+        && last_ident.args.is_some()
+    {
+        return qpath.span().shrink_to_lo().to(last_ident.ident.span);
+    }
+
+    qpath.span()
+}

src/tools/clippy/clippy_lints/src/cognitive_complexity.rs

@@ -110,7 +110,6 @@ impl CognitiveComplexity {
                 FnKind::ItemFn(ident, _, _) | FnKind::Method(ident, _) => ident.span,
                 FnKind::Closure => {
                     let header_span = body_span.with_hi(decl.output.span().lo());
-                    #[expect(clippy::range_plus_one)]
                     if let Some(range) = header_span.map_range(cx, |_, src, range| {
                         let mut idxs = src.get(range.clone())?.match_indices('|');
                         Some(range.start + idxs.next()?.0..range.start + idxs.next()?.0 + 1)

src/tools/clippy/clippy_lints/src/copies.rs

@@ -1,5 +1,6 @@
 use clippy_config::Conf;
 use clippy_utils::diagnostics::{span_lint, span_lint_and_note, span_lint_and_then};
+use clippy_utils::higher::has_let_expr;
 use clippy_utils::source::{IntoSpan, SpanRangeExt, first_line_of_span, indent_of, reindent_multiline, snippet};
 use clippy_utils::ty::{InteriorMut, needs_ordered_drop};
 use clippy_utils::visitors::for_each_expr_without_closures;
@@ -11,7 +12,7 @@ use clippy_utils::{
 use core::iter;
 use core::ops::ControlFlow;
 use rustc_errors::Applicability;
-use rustc_hir::{BinOpKind, Block, Expr, ExprKind, HirId, HirIdSet, LetStmt, Node, Stmt, StmtKind, intravisit};
+use rustc_hir::{Block, Expr, ExprKind, HirId, HirIdSet, LetStmt, Node, Stmt, StmtKind, intravisit};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty::TyCtxt;
 use rustc_session::impl_lint_pass;
@@ -189,24 +190,13 @@ impl<'tcx> LateLintPass<'tcx> for CopyAndPaste<'tcx> {
     }
 }
 
-/// Checks if the given expression is a let chain.
-fn contains_let(e: &Expr<'_>) -> bool {
-    match e.kind {
-        ExprKind::Let(..) => true,
-        ExprKind::Binary(op, lhs, rhs) if op.node == BinOpKind::And => {
-            matches!(lhs.kind, ExprKind::Let(..)) || contains_let(rhs)
-        },
-        _ => false,
-    }
-}
-
 fn lint_if_same_then_else(cx: &LateContext<'_>, conds: &[&Expr<'_>], blocks: &[&Block<'_>]) -> bool {
     let mut eq = SpanlessEq::new(cx);
     blocks
         .array_windows::<2>()
         .enumerate()
         .fold(true, |all_eq, (i, &[lhs, rhs])| {
-            if eq.eq_block(lhs, rhs) && !contains_let(conds[i]) && conds.get(i + 1).is_none_or(|e| !contains_let(e)) {
+            if eq.eq_block(lhs, rhs) && !has_let_expr(conds[i]) && conds.get(i + 1).is_none_or(|e| !has_let_expr(e)) {
                 span_lint_and_note(
                     cx,
                     IF_SAME_THEN_ELSE,