diff --git a/src/librustc/infer/error_reporting/mod.rs b/src/librustc/infer/error_reporting/mod.rs index 8d0ead5c8fe9..2ffcd2c4ace7 100644 --- a/src/librustc/infer/error_reporting/mod.rs +++ b/src/librustc/infer/error_reporting/mod.rs @@ -662,19 +662,22 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { } } _ => { + // `last_ty` can be `!`, `expected` will have better info when present. + let t = self.resolve_vars_if_possible(&match exp_found { + Some(ty::error::ExpectedFound { expected, .. }) => expected, + _ => last_ty, + }); let msg = "`match` arms have incompatible types"; err.span_label(cause.span, msg); if prior_arms.len() <= 4 { for sp in prior_arms { - err.span_label(*sp, format!( - "this is found to be of type `{}`", - self.resolve_vars_if_possible(&last_ty), - )); + err.span_label( *sp, format!("this is found to be of type `{}`", t)); } } else if let Some(sp) = prior_arms.last() { - err.span_label(*sp, format!( - "this and all prior arms are found to be of type `{}`", last_ty, - )); + err.span_label( + *sp, + format!("this and all prior arms are found to be of type `{}`", t), + ); } } }, @@ -1143,27 +1146,6 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { } (_, false, _) => { if let Some(exp_found) = exp_found { - let (def_id, ret_ty) = match exp_found.found.sty { - ty::FnDef(def, _) => { - (Some(def), Some(self.tcx.fn_sig(def).output())) - } - _ => (None, None), - }; - - let exp_is_struct = match exp_found.expected.sty { - ty::Adt(def, _) => def.is_struct(), - _ => false, - }; - - if let (Some(def_id), Some(ret_ty)) = (def_id, ret_ty) { - if exp_is_struct && &exp_found.expected == ret_ty.skip_binder() { - let message = format!( - "did you mean `{}(/* fields */)`?", - self.tcx.def_path_str(def_id) - ); - diag.span_label(span, message); - } - } self.suggest_as_ref_where_appropriate(span, &exp_found, diag); } diff --git a/src/test/ui/match/match-arm-resolving-to-never.rs b/src/test/ui/match/match-arm-resolving-to-never.rs new file mode 100644 index 000000000000..8f54023305e8 --- /dev/null +++ b/src/test/ui/match/match-arm-resolving-to-never.rs @@ -0,0 +1,19 @@ +enum E { + A, + B, + C, + D, + E, + F, +} + +fn main() { + match E::F { + E::A => 1, + E::B => 2, + E::C => 3, + E::D => 4, + E::E => unimplemented!(""), + E::F => "", //~ ERROR match arms have incompatible types + }; +} diff --git a/src/test/ui/match/match-arm-resolving-to-never.stderr b/src/test/ui/match/match-arm-resolving-to-never.stderr new file mode 100644 index 000000000000..24ce97f86e76 --- /dev/null +++ b/src/test/ui/match/match-arm-resolving-to-never.stderr @@ -0,0 +1,22 @@ +error[E0308]: match arms have incompatible types + --> $DIR/match-arm-resolving-to-never.rs:17:17 + | +LL | / match E::F { +LL | | E::A => 1, +LL | | E::B => 2, +LL | | E::C => 3, +LL | | E::D => 4, +LL | | E::E => unimplemented!(""), + | | ------------------ this and all prior arms are found to be of type `{integer}` +LL | | E::F => "", + | | ^^ expected integer, found reference +LL | | }; + | |_____- `match` arms have incompatible types + | + = note: expected type `{integer}` + found type `&'static str` + = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info) + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0308`.