check_pat_tuple: use pattern_cause

Author: Centril

src/librustc_typeck/check/pat.rs

@@ -918,7 +918,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         });
         let element_tys = tcx.mk_substs(element_tys_iter);
         let pat_ty = tcx.mk_ty(ty::Tuple(element_tys));
-        if let Some(mut err) = self.demand_eqtype_diag(span, expected, pat_ty) {
+        if let Some(mut err) = self.demand_eqtype_pat_diag(span, expected, pat_ty, ti) {
             err.emit();
             // Walk subpatterns with an expected type of `err` in this case to silence
             // further errors being emitted when using the bindings. #50333

src/test/ui/elide-errors-on-mismatched-tuple.stderr

@@ -2,7 +2,9 @@ error[E0308]: mismatched types
   --> $DIR/elide-errors-on-mismatched-tuple.rs:14:9
    |
 LL |     let (a, b, c) = (A::new(), A::new()); // This tuple is 2 elements, should be three
-   |         ^^^^^^^^^ expected a tuple with 2 elements, found one with 3 elements
+   |         ^^^^^^^^^   -------------------- this expression has type `(A, A)`
+   |         |
+   |         expected a tuple with 2 elements, found one with 3 elements
    |
    = note: expected tuple `(A, A)`
               found tuple `(_, _, _)`

src/test/ui/issues/issue-5100.stderr

@@ -12,6 +12,8 @@ LL |         A::B => (),
 error[E0308]: mismatched types
   --> $DIR/issue-5100.rs:17:9
    |
+LL |     match (true, false) {
+   |           ------------- this expression has type `(bool, bool)`
 LL |         (true, false, false) => ()
    |         ^^^^^^^^^^^^^^^^^^^^ expected a tuple with 2 elements, found one with 3 elements
    |
@@ -21,6 +23,8 @@ LL |         (true, false, false) => ()
 error[E0308]: mismatched types
   --> $DIR/issue-5100.rs:25:9
    |
+LL |     match (true, false) {
+   |           ------------- this expression has type `(bool, bool)`
 LL |         (true, false, false) => ()
    |         ^^^^^^^^^^^^^^^^^^^^ expected a tuple with 2 elements, found one with 3 elements
    |

src/test/ui/pattern/pat-tuple-bad-type.stderr

@@ -12,6 +12,8 @@ LL |         (..) => {}
 error[E0308]: mismatched types
   --> $DIR/pat-tuple-bad-type.rs:10:9
    |
+LL |     match 0u8 {
+   |           --- this expression has type `u8`
 LL |         (..) => {}
    |         ^^^^ expected `u8`, found `()`
 

src/test/ui/pattern/pat-tuple-overfield.stderr

@@ -1,6 +1,8 @@
 error[E0308]: mismatched types
   --> $DIR/pat-tuple-overfield.rs:5:9
    |
+LL |     match (1, 2, 3) {
+   |           --------- this expression has type `({integer}, {integer}, {integer})`
 LL |         (1, 2, 3, 4) => {}
    |         ^^^^^^^^^^^^ expected a tuple with 3 elements, found one with 4 elements
    |
@@ -10,6 +12,9 @@ LL |         (1, 2, 3, 4) => {}
 error[E0308]: mismatched types
   --> $DIR/pat-tuple-overfield.rs:6:9
    |
+LL |     match (1, 2, 3) {
+   |           --------- this expression has type `({integer}, {integer}, {integer})`
+LL |         (1, 2, 3, 4) => {}
 LL |         (1, 2, .., 3, 4) => {}
    |         ^^^^^^^^^^^^^^^^ expected a tuple with 3 elements, found one with 4 elements
    |

src/test/ui/suppressed-error.stderr

@@ -2,7 +2,9 @@ error[E0308]: mismatched types
   --> $DIR/suppressed-error.rs:2:9
    |
 LL |     let (x, y) = ();
-   |         ^^^^^^ expected `()`, found tuple
+   |         ^^^^^^   -- this expression has type `()`
+   |         |
+   |         expected `()`, found tuple
    |
    = note: expected unit type `()`
                   found tuple `(_, _)`