diff options
Diffstat (limited to 'src/librustc')
| -rw-r--r-- | src/librustc/error_codes.rs | 2 | ||||
| -rw-r--r-- | src/librustc/infer/error_reporting/mod.rs | 2 | ||||
| -rw-r--r-- | src/librustc/traits/error_reporting.rs | 5 | ||||
| -rw-r--r-- | src/librustc/traits/object_safety.rs | 72 |
4 files changed, 50 insertions, 31 deletions
diff --git a/src/librustc/error_codes.rs b/src/librustc/error_codes.rs index 2d09013f675..937a9ea6c1b 100644 --- a/src/librustc/error_codes.rs +++ b/src/librustc/error_codes.rs @@ -39,7 +39,7 @@ Generally, `Self: Sized` is used to indicate that the trait should not be used as a trait object. If the trait comes from your own crate, consider removing this restriction. -### Method references the `Self` type in its arguments or return type +### Method references the `Self` type in its parameters or return type This happens when a trait has a method like the following: diff --git a/src/librustc/infer/error_reporting/mod.rs b/src/librustc/infer/error_reporting/mod.rs index e684ccfeeb7..bf9cb79fb8a 100644 --- a/src/librustc/infer/error_reporting/mod.rs +++ b/src/librustc/infer/error_reporting/mod.rs @@ -1627,7 +1627,7 @@ impl<'tcx> ObligationCause<'tcx> { MainFunctionType => Error0580("main function has wrong type"), StartFunctionType => Error0308("start function has wrong type"), IntrinsicType => Error0308("intrinsic has wrong type"), - MethodReceiver => Error0308("mismatched method receiver"), + MethodReceiver => Error0308("mismatched `self` parameter type"), // In the case where we have no more specific thing to // say, also take a look at the error code, maybe we can diff --git a/src/librustc/traits/error_reporting.rs b/src/librustc/traits/error_reporting.rs index b38e1f5f839..03cc00d87e3 100644 --- a/src/librustc/traits/error_reporting.rs +++ b/src/librustc/traits/error_reporting.rs @@ -1384,7 +1384,10 @@ impl<'tcx> TyCtxt<'tcx> { let mut reported_violations = FxHashSet::default(); for violation in violations { if reported_violations.insert(violation.clone()) { - err.note(&violation.error_msg()); + match violation.span() { + Some(span) => err.span_label(span, violation.error_msg()), + None => err.note(&violation.error_msg()), + }; } } Some(err) diff --git a/src/librustc/traits/object_safety.rs b/src/librustc/traits/object_safety.rs index 7ea7bf0257c..f7f459cd27f 100644 --- a/src/librustc/traits/object_safety.rs +++ b/src/librustc/traits/object_safety.rs @@ -20,7 +20,7 @@ use std::borrow::Cow; use std::iter::{self}; use syntax::ast::{self}; use syntax::symbol::InternedString; -use syntax_pos::Span; +use syntax_pos::{Span, DUMMY_SP}; #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)] pub enum ObjectSafetyViolation { @@ -32,10 +32,10 @@ pub enum ObjectSafetyViolation { SupertraitSelf, /// Method has something illegal. - Method(ast::Name, MethodViolationCode), + Method(ast::Name, MethodViolationCode, Span), /// Associated const. - AssocConst(ast::Name), + AssocConst(ast::Name, Span), } impl ObjectSafetyViolation { @@ -46,22 +46,35 @@ impl ObjectSafetyViolation { ObjectSafetyViolation::SupertraitSelf => "the trait cannot use `Self` as a type parameter \ in the supertraits or where-clauses".into(), - ObjectSafetyViolation::Method(name, MethodViolationCode::StaticMethod) => - format!("method `{}` has no receiver", name).into(), - ObjectSafetyViolation::Method(name, MethodViolationCode::ReferencesSelf) => - format!("method `{}` references the `Self` type \ - in its arguments or return type", name).into(), - ObjectSafetyViolation::Method(name, - MethodViolationCode::WhereClauseReferencesSelf(_)) => - format!("method `{}` references the `Self` type in where clauses", name).into(), - ObjectSafetyViolation::Method(name, MethodViolationCode::Generic) => + ObjectSafetyViolation::Method(name, MethodViolationCode::StaticMethod, _) => + format!("associated function `{}` has no `self` parameter", name).into(), + ObjectSafetyViolation::Method(name, MethodViolationCode::ReferencesSelf, _) => format!( + "method `{}` references the `Self` type in its parameters or return type", + name, + ).into(), + ObjectSafetyViolation::Method( + name, + MethodViolationCode::WhereClauseReferencesSelf, + _, + ) => format!("method `{}` references the `Self` type in where clauses", name).into(), + ObjectSafetyViolation::Method(name, MethodViolationCode::Generic, _) => format!("method `{}` has generic type parameters", name).into(), - ObjectSafetyViolation::Method(name, MethodViolationCode::UndispatchableReceiver) => - format!("method `{}`'s receiver cannot be dispatched on", name).into(), - ObjectSafetyViolation::AssocConst(name) => + ObjectSafetyViolation::Method(name, MethodViolationCode::UndispatchableReceiver, _) => + format!("method `{}`'s `self` parameter cannot be dispatched on", name).into(), + ObjectSafetyViolation::AssocConst(name, _) => format!("the trait cannot contain associated consts like `{}`", name).into(), } } + + pub fn span(&self) -> Option<Span> { + // When `span` comes from a separate crate, it'll be `DUMMY_SP`. Treat it as `None` so + // diagnostics use a `note` instead of a `span_label`. + match *self { + ObjectSafetyViolation::AssocConst(_, span) | + ObjectSafetyViolation::Method(_, _, span) if span != DUMMY_SP => Some(span), + _ => None, + } + } } /// Reasons a method might not be object-safe. @@ -74,7 +87,7 @@ pub enum MethodViolationCode { ReferencesSelf, /// e.g., `fn foo(&self) where Self: Clone` - WhereClauseReferencesSelf(Span), + WhereClauseReferencesSelf, /// e.g., `fn foo<A>()` Generic, @@ -88,9 +101,10 @@ impl<'tcx> TyCtxt<'tcx> { /// astconv -- currently, `Self` in supertraits. This is needed /// because `object_safety_violations` can't be used during /// type collection. - pub fn astconv_object_safety_violations(self, trait_def_id: DefId) - -> Vec<ObjectSafetyViolation> - { + pub fn astconv_object_safety_violations( + self, + trait_def_id: DefId, + ) -> Vec<ObjectSafetyViolation> { debug_assert!(self.generics_of(trait_def_id).has_self); let violations = traits::supertrait_def_ids(self, trait_def_id) .filter(|&def_id| self.predicates_reference_self(def_id, true)) @@ -128,7 +142,7 @@ impl<'tcx> TyCtxt<'tcx> { } match self.virtual_call_violation_for_method(trait_def_id, method) { - None | Some(MethodViolationCode::WhereClauseReferencesSelf(_)) => true, + None | Some(MethodViolationCode::WhereClauseReferencesSelf) => true, Some(_) => false, } } @@ -138,12 +152,15 @@ impl<'tcx> TyCtxt<'tcx> { let mut violations: Vec<_> = self.associated_items(trait_def_id) .filter(|item| item.kind == ty::AssocKind::Method) .filter_map(|item| - self.object_safety_violation_for_method(trait_def_id, &item) - .map(|code| ObjectSafetyViolation::Method(item.ident.name, code)) + self.object_safety_violation_for_method(trait_def_id, &item).map(|code| { + ObjectSafetyViolation::Method(item.ident.name, code, item.ident.span) + }) ).filter(|violation| { - if let ObjectSafetyViolation::Method(_, - MethodViolationCode::WhereClauseReferencesSelf(span)) = violation - { + if let ObjectSafetyViolation::Method( + _, + MethodViolationCode::WhereClauseReferencesSelf, + span, + ) = violation { // Using `CRATE_NODE_ID` is wrong, but it's hard to get a more precise id. // It's also hard to get a use site span, so we use the method definition span. self.lint_node_note( @@ -169,7 +186,7 @@ impl<'tcx> TyCtxt<'tcx> { violations.extend(self.associated_items(trait_def_id) .filter(|item| item.kind == ty::AssocKind::Const) - .map(|item| ObjectSafetyViolation::AssocConst(item.ident.name))); + .map(|item| ObjectSafetyViolation::AssocConst(item.ident.name, item.ident.span))); debug!("object_safety_violations_for_trait(trait_def_id={:?}) = {:?}", trait_def_id, @@ -325,8 +342,7 @@ impl<'tcx> TyCtxt<'tcx> { .visit_tys_shallow(|t| { self.contains_illegal_self_type_reference(trait_def_id, t) }) { - let span = self.def_span(method.def_id); - return Some(MethodViolationCode::WhereClauseReferencesSelf(span)); + return Some(MethodViolationCode::WhereClauseReferencesSelf); } let receiver_ty = self.liberate_late_bound_regions( |