use rustc_hir::{ExprKind, Node, QPath};
use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
use rustc_infer::traits::Obligation;
+use rustc_span::symbol::kw;
use rustc_span::{source_map, FileName, Span};
use syntax::ast;
use syntax::util::lev_distance;
let type_is_local = self.type_derefs_to_local(span, rcvr_ty, source);
+ let mut arbitrary_rcvr = vec![];
// There are no traits implemented, so lets suggest some traits to
// implement, by finding ones that have the item name, and are
// legal to implement.
&& self
.associated_item(info.def_id, item_name, Namespace::ValueNS)
.filter(|item| {
+ if let ty::AssocKind::Method = item.kind {
+ let id = self.tcx.hir().as_local_hir_id(item.def_id);
+ if let Some(hir::Node::TraitItem(hir::TraitItem {
+ kind: hir::TraitItemKind::Method(fn_sig, method),
+ ..
+ })) = id.map(|id| self.tcx.hir().get(id))
+ {
+ let self_first_arg = match method {
+ hir::TraitMethod::Required([ident, ..]) => {
+ ident.name == kw::SelfLower
+ }
+ hir::TraitMethod::Provided(body_id) => {
+ match &self.tcx.hir().body(*body_id).params[..] {
+ [hir::Param {
+ pat:
+ hir::Pat {
+ kind:
+ hir::PatKind::Binding(
+ _,
+ _,
+ ident,
+ ..,
+ ),
+ ..
+ },
+ ..
+ }, ..] => ident.name == kw::SelfLower,
+ _ => false,
+ }
+ }
+ _ => false,
+ };
+
+ if !fn_sig.decl.implicit_self.has_implicit_self()
+ && self_first_arg
+ {
+ if let Some(ty) = fn_sig.decl.inputs.get(0) {
+ arbitrary_rcvr.push(ty.span);
+ }
+ return false;
+ }
+ }
+ }
// We only want to suggest public or local traits (#45781).
item.vis == ty::Visibility::Public || info.def_id.is_local()
})
.is_some()
})
.collect::<Vec<_>>();
+ for span in &arbitrary_rcvr {
+ err.span_label(
+ *span,
+ "the method might not be found because of this arbitrary self type",
+ );
+ }
if !candidates.is_empty() {
// Sort from most relevant to least relevant.
error[E0599]: no method named `foo` found for reference `&dyn Foo` in the current scope
--> $DIR/issue-5153.rs:10:27
|
-LL | trait Foo {
- | --------- `Foo` defines an item `foo`, perhaps you need to implement it
+LL | fn foo(self: Box<Self>);
+ | --------- the method might not be found because of this arbitrary self type
...
LL | (&5isize as &dyn Foo).foo();
| ^^^ method not found in `&dyn Foo`
- |
- = help: items from traits can only be used if the trait is implemented and in scope
error: aborting due to previous error
error[E0599]: no method named `owned` found for reference `&dyn Foo` in the current scope
--> $DIR/object-pointer-types.rs:11:7
|
-LL | trait Foo {
- | --------- `Foo` defines an item `owned`, perhaps you need to implement it
+LL | fn owned(self: Box<Self>);
+ | --------- the method might not be found because of this arbitrary self type
...
LL | x.owned();
| ^^^^^ method not found in `&dyn Foo`
- |
- = help: items from traits can only be used if the trait is implemented and in scope
error[E0599]: no method named `owned` found for mutable reference `&mut dyn Foo` in the current scope
--> $DIR/object-pointer-types.rs:17:7
|
-LL | trait Foo {
- | --------- `Foo` defines an item `owned`, perhaps you need to implement it
+LL | fn owned(self: Box<Self>);
+ | --------- the method might not be found because of this arbitrary self type
...
LL | x.owned();
| ^^^^^ method not found in `&mut dyn Foo`
- |
- = help: items from traits can only be used if the trait is implemented and in scope
error[E0599]: no method named `managed` found for struct `std::boxed::Box<(dyn Foo + 'static)>` in the current scope
--> $DIR/object-pointer-types.rs:23:7
--> $DIR/point-at-arbitrary-self-type-trait-method.rs:9:7
|
LL | trait B { fn foo(self: Box<Self>); }
- | ------- --- the method is available for `std::boxed::Box<A>` here
- | |
- | `B` defines an item `foo`, perhaps you need to implement it
+ | --- --------- the method might not be found because of this arbitrary self type
+ | |
+ | the method is available for `std::boxed::Box<A>` here
LL | struct A;
| --------- method `foo` not found for this
...
LL | A.foo()
| ^^^ method not found in `A`
- |
- = help: items from traits can only be used if the trait is implemented and in scope
error: aborting due to previous error