Auto merge of rust-lang#78662 - sexxi-goose:add_expr_id_to_delegate, r=nikomatsakis

Provide diagnostic suggestion in ExprUseVisitor Delegate

The [Delegate trait](https://github.com/rust-lang/rust/blob/981346fc07dd5ef414c5b1b21999f7604cece006/compiler/rustc_typeck/src/expr_use_visitor.rs#L28-L38) currently use `PlaceWithHirId` which is composed of Hir `Place` and the
corresponding expression id.

Even though this is an accurate way of expressing how a Place is used,
it can cause confusion during diagnostics.

Eg:

```
let arr : [String; 5];

let [a, ...]     =   arr;
 ^^^ E1 ^^^      =  ^^E2^^
 ```

 Here `arr` is moved because of the binding created E1. However, when we
 point to E1 in diagnostics with the message `arr` was moved, it can be
 confusing.  Rather we would like to report E2 to the user.

 Closes: rust-lang/project-rfc-2229#20

r? `@ghost`

Author: bors

clippy_lints/src/escape.rs

@@ -115,7 +115,7 @@ fn is_argument(map: rustc_middle::hir::map::Map<'_>, id: HirId) -> bool {
 }
 
 impl<'a, 'tcx> Delegate<'tcx> for EscapeDelegate<'a, 'tcx> {
-    fn consume(&mut self, cmt: &PlaceWithHirId<'tcx>, mode: ConsumeMode) {
+    fn consume(&mut self, cmt: &PlaceWithHirId<'tcx>, _: HirId, mode: ConsumeMode) {
         if cmt.place.projections.is_empty() {
             if let PlaceBase::Local(lid) = cmt.place.base {
                 if let ConsumeMode::Move = mode {
@@ -135,15 +135,15 @@ impl<'a, 'tcx> Delegate<'tcx> for EscapeDelegate<'a, 'tcx> {
         }
     }
 
-    fn borrow(&mut self, cmt: &PlaceWithHirId<'tcx>, _: ty::BorrowKind) {
+    fn borrow(&mut self, cmt: &PlaceWithHirId<'tcx>, _: HirId, _: ty::BorrowKind) {
         if cmt.place.projections.is_empty() {
             if let PlaceBase::Local(lid) = cmt.place.base {
                 self.set.remove(&lid);
             }
         }
     }
 
-    fn mutate(&mut self, cmt: &PlaceWithHirId<'tcx>) {
+    fn mutate(&mut self, cmt: &PlaceWithHirId<'tcx>, _: HirId) {
         if cmt.place.projections.is_empty() {
             let map = &self.cx.tcx.hir();
             if is_argument(*map, cmt.hir_id) {

clippy_lints/src/loops.rs

@@ -1957,28 +1957,28 @@ struct MutatePairDelegate<'a, 'tcx> {
 }
 
 impl<'tcx> Delegate<'tcx> for MutatePairDelegate<'_, 'tcx> {
-    fn consume(&mut self, _: &PlaceWithHirId<'tcx>, _: ConsumeMode) {}
+    fn consume(&mut self, _: &PlaceWithHirId<'tcx>, _: HirId, _: ConsumeMode) {}
 
-    fn borrow(&mut self, cmt: &PlaceWithHirId<'tcx>, bk: ty::BorrowKind) {
+    fn borrow(&mut self, cmt: &PlaceWithHirId<'tcx>, diag_expr_id: HirId, bk: ty::BorrowKind) {
         if let ty::BorrowKind::MutBorrow = bk {
             if let PlaceBase::Local(id) = cmt.place.base {
                 if Some(id) == self.hir_id_low {
-                    self.span_low = Some(self.cx.tcx.hir().span(cmt.hir_id))
+                    self.span_low = Some(self.cx.tcx.hir().span(diag_expr_id))
                 }
                 if Some(id) == self.hir_id_high {
-                    self.span_high = Some(self.cx.tcx.hir().span(cmt.hir_id))
+                    self.span_high = Some(self.cx.tcx.hir().span(diag_expr_id))
                 }
             }
         }
     }
 
-    fn mutate(&mut self, cmt: &PlaceWithHirId<'tcx>) {
+    fn mutate(&mut self, cmt: &PlaceWithHirId<'tcx>, diag_expr_id: HirId) {
         if let PlaceBase::Local(id) = cmt.place.base {
             if Some(id) == self.hir_id_low {
-                self.span_low = Some(self.cx.tcx.hir().span(cmt.hir_id))
+                self.span_low = Some(self.cx.tcx.hir().span(diag_expr_id))
             }
             if Some(id) == self.hir_id_high {
-                self.span_high = Some(self.cx.tcx.hir().span(cmt.hir_id))
+                self.span_high = Some(self.cx.tcx.hir().span(diag_expr_id))
             }
         }
     }

clippy_lints/src/needless_pass_by_value.rs

@@ -325,13 +325,13 @@ impl MovedVariablesCtxt {
 }
 
 impl<'tcx> euv::Delegate<'tcx> for MovedVariablesCtxt {
-    fn consume(&mut self, cmt: &euv::PlaceWithHirId<'tcx>, mode: euv::ConsumeMode) {
+    fn consume(&mut self, cmt: &euv::PlaceWithHirId<'tcx>, _: HirId, mode: euv::ConsumeMode) {
         if let euv::ConsumeMode::Move = mode {
             self.move_common(cmt);
         }
     }
 
-    fn borrow(&mut self, _: &euv::PlaceWithHirId<'tcx>, _: ty::BorrowKind) {}
+    fn borrow(&mut self, _: &euv::PlaceWithHirId<'tcx>, _: HirId, _: ty::BorrowKind) {}
 
-    fn mutate(&mut self, _: &euv::PlaceWithHirId<'tcx>) {}
+    fn mutate(&mut self, _: &euv::PlaceWithHirId<'tcx>, _: HirId) {}
 }

clippy_lints/src/utils/usage.rs

@@ -68,15 +68,15 @@ impl<'tcx> MutVarsDelegate {
 }
 
 impl<'tcx> Delegate<'tcx> for MutVarsDelegate {
-    fn consume(&mut self, _: &PlaceWithHirId<'tcx>, _: ConsumeMode) {}
+    fn consume(&mut self, _: &PlaceWithHirId<'tcx>, _: HirId, _: ConsumeMode) {}
 
-    fn borrow(&mut self, cmt: &PlaceWithHirId<'tcx>, bk: ty::BorrowKind) {
+    fn borrow(&mut self, cmt: &PlaceWithHirId<'tcx>, _: HirId, bk: ty::BorrowKind) {
         if let ty::BorrowKind::MutBorrow = bk {
             self.update(&cmt)
         }
     }
 
-    fn mutate(&mut self, cmt: &PlaceWithHirId<'tcx>) {
+    fn mutate(&mut self, cmt: &PlaceWithHirId<'tcx>, _: HirId) {
         self.update(&cmt)
     }
 }