diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs index 30b2f43153e..8da06120873 100644 --- a/src/librustc_typeck/check/mod.rs +++ b/src/librustc_typeck/check/mod.rs @@ -995,7 +995,7 @@ fn check_impl_items_against_trait<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>, // Check existing impl methods to see if they are both present in trait // and compatible with trait signature for impl_item in impl_items { - let ty_impl_item = ccx.tcx.impl_or_trait_item(ccx.tcx.map.local_def_id(impl_item.id)); + let ty_impl_item = tcx.impl_or_trait_item(tcx.map.local_def_id(impl_item.id)); let ty_trait_item = trait_items.iter() .find(|ac| ac.name() == ty_impl_item.name()); @@ -1016,11 +1016,18 @@ fn check_impl_items_against_trait<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>, trait_const, &impl_trait_ref); } else { - span_err!(tcx.sess, impl_item.span, E0323, + let mut err = struct_span_err!(tcx.sess, impl_item.span, E0323, "item `{}` is an associated const, \ which doesn't match its trait `{:?}`", impl_const.name, - impl_trait_ref) + impl_trait_ref); + err.span_label(impl_item.span, &format!("does not match trait")); + // We can only get the spans from local trait definition + // Same for E0324 and E0325 + if let Some(trait_span) = tcx.map.span_if_local(ty_trait_item.def_id()) { + err.span_label(trait_span, &format!("original trait requirement")); + } + err.emit() } } hir::ImplItemKind::Method(ref sig, ref body) => { @@ -1039,11 +1046,16 @@ fn check_impl_items_against_trait<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>, &trait_method, &impl_trait_ref); } else { - span_err!(tcx.sess, impl_item.span, E0324, + let mut err = struct_span_err!(tcx.sess, impl_item.span, E0324, "item `{}` is an associated method, \ which doesn't match its trait `{:?}`", impl_method.name, - impl_trait_ref) + impl_trait_ref); + err.span_label(impl_item.span, &format!("does not match trait")); + if let Some(trait_span) = tcx.map.span_if_local(ty_trait_item.def_id()) { + err.span_label(trait_span, &format!("original trait requirement")); + } + err.emit() } } hir::ImplItemKind::Type(_) => { @@ -1057,11 +1069,16 @@ fn check_impl_items_against_trait<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>, overridden_associated_type = Some(impl_item); } } else { - span_err!(tcx.sess, impl_item.span, E0325, + let mut err = struct_span_err!(tcx.sess, impl_item.span, E0325, "item `{}` is an associated type, \ which doesn't match its trait `{:?}`", impl_type.name, - impl_trait_ref) + impl_trait_ref); + err.span_label(impl_item.span, &format!("does not match trait")); + if let Some(trait_span) = tcx.map.span_if_local(ty_trait_item.def_id()) { + err.span_label(trait_span, &format!("original trait requirement")); + } + err.emit() } } } diff --git a/src/test/compile-fail/impl-wrong-item-for-trait.rs b/src/test/compile-fail/impl-wrong-item-for-trait.rs index 9b3e28cbc01..6452e50d089 100644 --- a/src/test/compile-fail/impl-wrong-item-for-trait.rs +++ b/src/test/compile-fail/impl-wrong-item-for-trait.rs @@ -12,7 +12,9 @@ trait Foo { fn bar(&self); - const MY_CONST: u32; + //~^ NOTE original trait requirement + //~| NOTE original trait requirement + const MY_CONST: u32; //~ NOTE original trait requirement } pub struct FooConstForMethod; @@ -21,6 +23,7 @@ impl Foo for FooConstForMethod { //~^ ERROR E0046 const bar: u64 = 1; //~^ ERROR E0323 + //~| NOTE does not match trait const MY_CONST: u32 = 1; } @@ -31,6 +34,7 @@ impl Foo for FooMethodForConst { fn bar(&self) {} fn MY_CONST() {} //~^ ERROR E0324 + //~| NOTE does not match trait } pub struct FooTypeForMethod; @@ -39,6 +43,7 @@ impl Foo for FooTypeForMethod { //~^ ERROR E0046 type bar = u64; //~^ ERROR E0325 + //~| NOTE does not match trait const MY_CONST: u32 = 1; }