Do not point at macro invocation when providing inference context

Author: estebank

compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs

@@ -459,7 +459,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                             span,
                             format!("this is an iterator with items of type `{}`", args.type_at(0)),
                         );
-                    } else {
+                    } else if !span.overlaps(cause.span) {
                         let expected_ty = self.tcx.short_string(expected_ty, err.long_ty_path());
                         err.span_label(span, format!("this expression has type `{expected_ty}`"));
                     }

tests/ui/proc-macro/match-expander.rs

@@ -8,6 +8,5 @@ fn main() {
     match_expander::matcher!();
     //~^ ERROR: mismatched types
     //~| NOTE: expected `S`, found `bool`
-    //~| NOTE: this expression has type `S`
     //~| NOTE: in this expansion of match_expander::matcher!
 }

tests/ui/proc-macro/match-expander.stderr

@@ -2,10 +2,7 @@ error[E0308]: mismatched types
   --> $DIR/match-expander.rs:8:5
    |
 LL |     match_expander::matcher!();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |     |
-   |     expected `S`, found `bool`
-   |     this expression has type `S`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `S`, found `bool`
    |
    = note: this error originates in the macro `match_expander::matcher` (in Nightly builds, run with -Z macro-backtrace for more info)