From 9483db5052415464fcb59ab480479afdd35710a5 Mon Sep 17 00:00:00 2001 From: Giles Cope Date: Thu, 5 Sep 2019 00:08:52 +0100 Subject: [PATCH] Opaque type locations in error message for clarity. --- src/librustc/infer/error_reporting/mod.rs | 11 +++++++++-- src/test/ui/suggestions/opaque-type-error.stderr | 4 ++-- 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/src/librustc/infer/error_reporting/mod.rs b/src/librustc/infer/error_reporting/mod.rs index 9be73cf3c6d16..fdadda92010a5 100644 --- a/src/librustc/infer/error_reporting/mod.rs +++ b/src/librustc/infer/error_reporting/mod.rs @@ -1136,12 +1136,19 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { if let Some((expected, found)) = expected_found { match (terr, is_simple_error, expected == found) { (&TypeError::Sorts(ref values), false, true) => { + let sort_string = | a_type: Ty<'tcx> | + if let ty::Opaque(def_id, _) = a_type.sty { + format!(" (opaque type at {})", self.tcx.sess.source_map() + .mk_substr_filename(self.tcx.def_span(def_id))) + } else { + format!(" ({})", a_type.sort_string(self.tcx)) + }; diag.note_expected_found_extra( &"type", expected, found, - &format!(" ({})", values.expected.sort_string(self.tcx)), - &format!(" ({})", values.found.sort_string(self.tcx)), + &sort_string(values.expected), + &sort_string(values.found), ); } (_, false, _) => { diff --git a/src/test/ui/suggestions/opaque-type-error.stderr b/src/test/ui/suggestions/opaque-type-error.stderr index 3c9ea05aeceb2..450cbd4799fdc 100644 --- a/src/test/ui/suggestions/opaque-type-error.stderr +++ b/src/test/ui/suggestions/opaque-type-error.stderr @@ -10,8 +10,8 @@ LL | | thing_two() LL | | }.await | |_____- if and else have incompatible types | - = note: expected type `impl std::future::Future` (opaque type) - found type `impl std::future::Future` (opaque type) + = note: expected type `impl std::future::Future` (opaque type at <$DIR/opaque-type-error.rs:8:19>) + found type `impl std::future::Future` (opaque type at <$DIR/opaque-type-error.rs:12:19>) = note: distinct uses of `impl Trait` result in different opaque types = help: if both `Future`s have the same `Output` type, consider `.await`ing on both of them