Merging upstream version 1.72.1+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 36 insertions, 22 deletions

diff --git a/src/tools/clippy/clippy_lints/src/dereference.rs b/src/tools/clippy/clippy_lints/src/dereference.rs
index b27ffe73f..12f2f37e3 100644
--- a/src/tools/clippy/clippy_lints/src/dereference.rs
+++ b/src/tools/clippy/clippy_lints/src/dereference.rs
@@ -26,8 +26,8 @@ use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::mir::{Rvalue, StatementKind};
 use rustc_middle::ty::adjustment::{Adjust, Adjustment, AutoBorrow, AutoBorrowMutability};
 use rustc_middle::ty::{
-    self, Binder, BoundVariableKind, Clause, EarlyBinder, FnSig, GenericArgKind, List, ParamEnv, ParamTy,
-    PredicateKind, ProjectionPredicate, Ty, TyCtxt, TypeVisitableExt, TypeckResults,
+    self, Binder, BoundVariableKind, ClauseKind, EarlyBinder, FnSig, GenericArgKind, List, ParamEnv, ParamTy,
+    ProjectionPredicate, Ty, TyCtxt, TypeVisitableExt, TypeckResults,
 };
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::{symbol::sym, Span, Symbol};
@@ -56,9 +56,11 @@ declare_clippy_lint! {
     /// let b = &*a;
     /// ```
     ///
-    /// This lint excludes:
+    /// This lint excludes all of:
     /// ```rust,ignore
     /// let _ = d.unwrap().deref();
+    /// let _ = Foo::deref(&foo);
+    /// let _ = <Foo as Deref>::deref(&foo);
     /// ```
     #[clippy::version = "1.44.0"]
     pub EXPLICIT_DEREF_METHODS,
@@ -355,15 +357,17 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing<'tcx> {
                         //    start auto-deref.
                         // 4. If the chain of non-user-defined derefs ends with a mutable re-borrow, and re-borrow
                         //    adjustments will not be inserted automatically, then leave one further reference to avoid
-                        //    moving a mutable borrow.
-                        //    e.g.
-                        //        fn foo<T>(x: &mut Option<&mut T>, y: &mut T) {
-                        //            let x = match x {
-                        //                // Removing the borrow will cause `x` to be moved
-                        //                Some(x) => &mut *x,
-                        //                None => y
-                        //            };
-                        //        }
+                        //    moving a mutable borrow. e.g.
+                        //
+                        //    ```rust
+                        //    fn foo<T>(x: &mut Option<&mut T>, y: &mut T) {
+                        //        let x = match x {
+                        //            // Removing the borrow will cause `x` to be moved
+                        //            Some(x) => &mut *x,
+                        //            None => y
+                        //        };
+                        //    }
+                        //    ```
                         let deref_msg =
                             "this expression creates a reference which is immediately dereferenced by the compiler";
                         let borrow_msg = "this expression borrows a value the compiler would automatically borrow";
@@ -1133,7 +1137,7 @@ fn needless_borrow_impl_arg_position<'tcx>(
     let projection_predicates = predicates
         .iter()
         .filter_map(|predicate| {
-            if let PredicateKind::Clause(Clause::Projection(projection_predicate)) = predicate.kind().skip_binder() {
+            if let ClauseKind::Projection(projection_predicate) = predicate.kind().skip_binder() {
                 Some(projection_predicate)
             } else {
                 None
@@ -1147,7 +1151,7 @@ fn needless_borrow_impl_arg_position<'tcx>(
     if predicates
         .iter()
         .filter_map(|predicate| {
-            if let PredicateKind::Clause(Clause::Trait(trait_predicate)) = predicate.kind().skip_binder()
+            if let ClauseKind::Trait(trait_predicate) = predicate.kind().skip_binder()
                 && trait_predicate.trait_ref.self_ty() == param_ty.to_ty(cx.tcx)
             {
                 Some(trait_predicate.trait_ref.def_id)
@@ -1209,7 +1213,7 @@ fn needless_borrow_impl_arg_position<'tcx>(
         }
 
         predicates.iter().all(|predicate| {
-            if let PredicateKind::Clause(Clause::Trait(trait_predicate)) = predicate.kind().skip_binder()
+            if let ClauseKind::Trait(trait_predicate) = predicate.kind().skip_binder()
                 && cx.tcx.is_diagnostic_item(sym::IntoIterator, trait_predicate.trait_ref.def_id)
                 && let ty::Param(param_ty) = trait_predicate.self_ty().kind()
                 && let GenericArgKind::Type(ty) = substs_with_referent_ty[param_ty.index as usize].unpack()
@@ -1219,7 +1223,7 @@ fn needless_borrow_impl_arg_position<'tcx>(
                 return false;
             }
 
-            let predicate = EarlyBinder(predicate).subst(cx.tcx, &substs_with_referent_ty);
+            let predicate = EarlyBinder::bind(predicate).subst(cx.tcx, &substs_with_referent_ty);
             let obligation = Obligation::new(cx.tcx, ObligationCause::dummy(), cx.param_env, predicate);
             let infcx = cx.tcx.infer_ctxt().build();
             infcx.predicate_must_hold_modulo_regions(&obligation)
@@ -1292,8 +1296,8 @@ fn referent_used_exactly_once<'tcx>(
     possible_borrowers: &mut Vec<(LocalDefId, PossibleBorrowerMap<'tcx, 'tcx>)>,
     reference: &Expr<'tcx>,
 ) -> bool {
-    let mir = enclosing_mir(cx.tcx, reference.hir_id);
-    if let Some(local) = expr_local(cx.tcx, reference)
+    if let Some(mir) = enclosing_mir(cx.tcx, reference.hir_id)
+        && let Some(local) = expr_local(cx.tcx, reference)
         && let [location] = *local_assignments(mir, local).as_slice()
         && let Some(statement) = mir.basic_blocks[location.block].statements.get(location.statement_index)
         && let StatementKind::Assign(box (_, Rvalue::Ref(_, _, place))) = statement.kind
@@ -1424,6 +1428,7 @@ fn ty_auto_deref_stability<'tcx>(
                 continue;
             },
             ty::Param(_) => TyPosition::new_deref_stable_for_result(precedence, ty),
+            ty::Alias(ty::Weak, _) => unreachable!("should have been normalized away above"),
             ty::Alias(ty::Inherent, _) => unreachable!("inherent projection should have been normalized away above"),
             ty::Alias(ty::Projection, _) if ty.has_non_region_param() => {
                 TyPosition::new_deref_stable_for_result(precedence, ty)
@@ -1480,7 +1485,7 @@ fn report<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, state: State, data
             target_mut,
         } => {
             let mut app = Applicability::MachineApplicable;
-            let (expr_str, expr_is_macro_call) = snippet_with_context(cx, expr.span, data.span.ctxt(), "..", &mut app);
+            let (expr_str, _expr_is_macro_call) = snippet_with_context(cx, expr.span, data.span.ctxt(), "..", &mut app);
             let ty = cx.typeck_results().expr_ty(expr);
             let (_, ref_count) = peel_mid_ty_refs(ty);
             let deref_str = if ty_changed_count >= ref_count && ref_count != 0 {
@@ -1503,11 +1508,20 @@ fn report<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, state: State, data
                 "&"
             };
 
-            let expr_str = if !expr_is_macro_call && is_final_ufcs && expr.precedence().order() < PREC_PREFIX {
-                format!("({expr_str})")
+            // expr_str (the suggestion) is never shown if is_final_ufcs is true, since it's
+            // `expr.kind == ExprKind::Call`. Therefore, this is, afaik, always unnecessary.
+            /*
+            expr_str = if !expr_is_macro_call && is_final_ufcs && expr.precedence().order() < PREC_PREFIX {
+                Cow::Owned(format!("({expr_str})"))
             } else {
-                expr_str.into_owned()
+                expr_str
             };
+            */
+
+            // Fix #10850, do not lint if it's `Foo::deref` instead of `foo.deref()`.
+            if is_final_ufcs {
+                return;
+            }
 
             span_lint_and_sugg(
                 cx,