Rollup merge of #117655 - compiler-errors:method-tweaks, r=estebank

Method suggestion code tweaks

I was rummaging around the method suggestion code after https://github.com/rust-lang/rust/pull/117006#discussion_r1384153722 and saw a few things to simplify.

This is two unrelated commits, both in the same file. Review them separately, if you'd like.

r? estebank
This commit is contained in:
Matthias Krüger 2023-11-08 00:47:52 +01:00 committed by GitHub
commit f72e974e3f
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12 changed files with 178 additions and 198 deletions

View File

@ -13,7 +13,7 @@
YieldExprOutsideOfCoroutine,
};
use crate::fatally_break_rust;
use crate::method::{MethodCallComponents, SelfSource};
use crate::method::SelfSource;
use crate::type_error_struct;
use crate::Expectation::{self, ExpectCastableToType, ExpectHasType, NoExpectation};
use crate::{
@ -512,7 +512,7 @@ pub(crate) fn check_expr_path(
) -> Ty<'tcx> {
let tcx = self.tcx;
let (res, opt_ty, segs) =
self.resolve_ty_and_res_fully_qualified_call(qpath, expr.hir_id, expr.span);
self.resolve_ty_and_res_fully_qualified_call(qpath, expr.hir_id, expr.span, Some(args));
let ty = match res {
Res::Err => {
self.suggest_assoc_method_call(segs);
@ -1332,7 +1332,7 @@ fn check_method_call(
segment.ident,
SelfSource::MethodCall(rcvr),
error,
Some(MethodCallComponents { receiver: rcvr, args, full_expr: expr }),
Some(args),
expected,
false,
) {

View File

@ -797,6 +797,7 @@ pub fn resolve_ty_and_res_fully_qualified_call(
qpath: &'tcx QPath<'tcx>,
hir_id: hir::HirId,
span: Span,
args: Option<&'tcx [hir::Expr<'tcx>]>,
) -> (Res, Option<RawTy<'tcx>>, &'tcx [hir::PathSegment<'tcx>]) {
debug!(
"resolve_ty_and_res_fully_qualified_call: qpath={:?} hir_id={:?} span={:?}",
@ -898,7 +899,7 @@ pub fn resolve_ty_and_res_fully_qualified_call(
item_name,
SelfSource::QPath(qself),
error,
None,
args,
Expectation::NoExpectation,
trait_missing_method && span.edition().at_least_rust_2021(), // emits missing method for trait only after edition 2021
) {

View File

@ -7,7 +7,7 @@
pub mod probe;
mod suggest;
pub use self::suggest::{MethodCallComponents, SelfSource};
pub use self::suggest::SelfSource;
pub use self::MethodError::*;
use crate::errors::OpMethodGenericParams;

View File

@ -34,7 +34,7 @@
use rustc_span::def_id::DefIdSet;
use rustc_span::symbol::{kw, sym, Ident};
use rustc_span::Symbol;
use rustc_span::{edit_distance, source_map, ExpnKind, FileName, MacroKind, Span};
use rustc_span::{edit_distance, ExpnKind, FileName, MacroKind, Span};
use rustc_trait_selection::infer::InferCtxtExt;
use rustc_trait_selection::traits::error_reporting::on_unimplemented::OnUnimplementedNote;
use rustc_trait_selection::traits::error_reporting::on_unimplemented::TypeErrCtxtExt as _;
@ -50,15 +50,6 @@
use std::cmp::{self, Ordering};
use std::iter;
/// After identifying that `full_expr` is a method call, we use this type to keep the expression's
/// components readily available to us to point at the right place in diagnostics.
#[derive(Debug, Clone, Copy)]
pub struct MethodCallComponents<'tcx> {
pub receiver: &'tcx hir::Expr<'tcx>,
pub args: &'tcx [hir::Expr<'tcx>],
pub full_expr: &'tcx hir::Expr<'tcx>,
}
impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
fn is_fn_ty(&self, ty: Ty<'tcx>, span: Span) -> bool {
let tcx = self.tcx;
@ -124,7 +115,7 @@ pub fn report_method_error(
item_name: Ident,
source: SelfSource<'tcx>,
error: MethodError<'tcx>,
args: Option<MethodCallComponents<'tcx>>,
args: Option<&'tcx [hir::Expr<'tcx>]>,
expected: Expectation<'tcx>,
trait_missing_method: bool,
) -> Option<DiagnosticBuilder<'_, ErrorGuaranteed>> {
@ -167,6 +158,7 @@ pub fn report_method_error(
self.note_candidates_on_method_error(
rcvr_ty,
item_name,
source,
args,
span,
&mut err,
@ -266,23 +258,23 @@ pub fn report_method_error(
fn suggest_missing_writer(
&self,
rcvr_ty: Ty<'tcx>,
args: MethodCallComponents<'tcx>,
rcvr_expr: &hir::Expr<'tcx>,
) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
let (ty_str, _ty_file) = self.tcx.short_ty_string(rcvr_ty);
let mut err = struct_span_err!(
self.tcx.sess,
args.receiver.span,
rcvr_expr.span,
E0599,
"cannot write into `{}`",
ty_str
);
err.span_note(
args.receiver.span,
rcvr_expr.span,
"must implement `io::Write`, `fmt::Write`, or have a `write_fmt` method",
);
if let ExprKind::Lit(_) = args.receiver.kind {
if let ExprKind::Lit(_) = rcvr_expr.kind {
err.span_help(
args.receiver.span.shrink_to_lo(),
rcvr_expr.span.shrink_to_lo(),
"a writer is needed before this format string",
);
};
@ -296,7 +288,7 @@ pub fn report_no_match_method_error(
rcvr_ty: Ty<'tcx>,
item_name: Ident,
source: SelfSource<'tcx>,
args: Option<MethodCallComponents<'tcx>>,
args: Option<&'tcx [hir::Expr<'tcx>]>,
sugg_span: Span,
no_match_data: &mut NoMatchData<'tcx>,
expected: Expectation<'tcx>,
@ -377,23 +369,25 @@ pub fn report_no_match_method_error(
tcx.is_diagnostic_item(sym::write_macro, def_id)
|| tcx.is_diagnostic_item(sym::writeln_macro, def_id)
}) && item_name.name == Symbol::intern("write_fmt");
let mut err = if is_write && let Some(args) = args {
self.suggest_missing_writer(rcvr_ty, args)
} else {
tcx.sess.create_err(NoAssociatedItem {
span,
item_kind,
item_name,
ty_prefix: if trait_missing_method {
// FIXME(mu001999) E0599 maybe not suitable here because it is for types
Cow::from("trait")
} else {
rcvr_ty.prefix_string(self.tcx)
},
ty_str: ty_str_reported,
trait_missing_method,
})
};
let mut err =
if is_write && let SelfSource::MethodCall(rcvr_expr) = source
{
self.suggest_missing_writer(rcvr_ty, rcvr_expr)
} else {
tcx.sess.create_err(NoAssociatedItem {
span,
item_kind,
item_name,
ty_prefix: if trait_missing_method {
// FIXME(mu001999) E0599 maybe not suitable here because it is for types
Cow::from("trait")
} else {
rcvr_ty.prefix_string(self.tcx)
},
ty_str: ty_str_reported,
trait_missing_method,
})
};
if tcx.sess.source_map().is_multiline(sugg_span) {
err.span_label(sugg_span.with_hi(span.lo()), "");
}
@ -409,7 +403,10 @@ pub fn report_no_match_method_error(
err.downgrade_to_delayed_bug();
}
self.find_builder_fn(&mut err, rcvr_ty, source);
if matches!(source, SelfSource::QPath(_)) && args.is_some() {
self.find_builder_fn(&mut err, rcvr_ty);
}
if tcx.ty_is_opaque_future(rcvr_ty) && item_name.name == sym::poll {
err.help(format!(
"method `poll` found on `Pin<&mut {ty_str}>`, \
@ -523,6 +520,7 @@ pub fn report_no_match_method_error(
self.note_candidates_on_method_error(
rcvr_ty,
item_name,
source,
args,
span,
&mut err,
@ -533,6 +531,7 @@ pub fn report_no_match_method_error(
self.note_candidates_on_method_error(
rcvr_ty,
item_name,
source,
args,
span,
&mut err,
@ -976,7 +975,7 @@ trait bound{s}",
unsatisfied_bounds = true;
}
} else if let ty::Adt(def, targs) = rcvr_ty.kind()
&& let Some(args) = args
&& let SelfSource::MethodCall(rcvr_expr) = source
{
// This is useful for methods on arbitrary self types that might have a simple
// mutability difference, like calling a method on `Pin<&mut Self>` that is on
@ -999,8 +998,8 @@ trait bound{s}",
rcvr_ty,
&item_segment,
span,
args.full_expr,
args.receiver,
tcx.hir().get_parent(rcvr_expr.hir_id).expect_expr(),
rcvr_expr,
) {
err.span_note(
tcx.def_span(method.def_id),
@ -1169,7 +1168,7 @@ trait bound{s}",
span,
rcvr_ty,
item_name,
args.map(|MethodCallComponents { args, .. }| args.len() + 1),
args.map(|args| args.len() + 1),
source,
no_match_data.out_of_scope_traits.clone(),
&unsatisfied_predicates,
@ -1250,7 +1249,8 @@ fn note_candidates_on_method_error(
&self,
rcvr_ty: Ty<'tcx>,
item_name: Ident,
args: Option<MethodCallComponents<'tcx>>,
self_source: SelfSource<'tcx>,
args: Option<&'tcx [hir::Expr<'tcx>]>,
span: Span,
err: &mut Diagnostic,
sources: &mut Vec<CandidateSource>,
@ -1320,38 +1320,21 @@ fn note_candidates_on_method_error(
}
if let Some(sugg_span) = sugg_span
&& let Some(trait_ref) = self.tcx.impl_trait_ref(impl_did)
{
let path = self.tcx.def_path_str(trait_ref.skip_binder().def_id);
let ty = match item.kind {
ty::AssocKind::Const | ty::AssocKind::Type => impl_ty,
ty::AssocKind::Fn => self
.tcx
.fn_sig(item.def_id)
.instantiate_identity()
.inputs()
.skip_binder()
.get(0)
.filter(|ty| ty.is_ref() && !rcvr_ty.is_ref())
.copied()
.unwrap_or(rcvr_ty),
};
if let Some(sugg) = print_disambiguation_help(
item_name,
args,
&& let Some(sugg) = print_disambiguation_help(
self.tcx,
err,
path,
ty,
Some(impl_ty),
item.kind,
self.tcx.def_kind_descr(item.kind.as_def_kind(), item.def_id),
sugg_span,
self_source,
args,
trait_ref.instantiate(
self.tcx,
self.fresh_args_for_item(sugg_span, impl_did)
).with_self_ty(self.tcx, rcvr_ty),
idx,
self.tcx.sess.source_map(),
item.fn_has_self_parameter,
) {
suggs.push(sugg);
}
sugg_span,
item,
)
{
suggs.push(sugg);
}
}
CandidateSource::Trait(trait_did) => {
@ -1373,24 +1356,23 @@ fn note_candidates_on_method_error(
err.span_note(item_span, msg);
None
};
if let Some(sugg_span) = sugg_span {
let path = self.tcx.def_path_str(trait_did);
if let Some(sugg) = print_disambiguation_help(
item_name,
args,
if let Some(sugg_span) = sugg_span
&& let Some(sugg) = print_disambiguation_help(
self.tcx,
err,
path,
rcvr_ty,
None,
item.kind,
self.tcx.def_kind_descr(item.kind.as_def_kind(), item.def_id),
sugg_span,
self_source,
args,
ty::TraitRef::new(
self.tcx,
trait_did,
self.fresh_args_for_item(sugg_span, trait_did)
).with_self_ty(self.tcx, rcvr_ty),
idx,
self.tcx.sess.source_map(),
item.fn_has_self_parameter,
) {
suggs.push(sugg);
}
sugg_span,
item,
)
{
suggs.push(sugg);
}
}
}
@ -1410,18 +1392,10 @@ fn note_candidates_on_method_error(
/// Look at all the associated functions without receivers in the type's inherent impls
/// to look for builders that return `Self`, `Option<Self>` or `Result<Self, _>`.
fn find_builder_fn(&self, err: &mut Diagnostic, rcvr_ty: Ty<'tcx>, source: SelfSource<'tcx>) {
fn find_builder_fn(&self, err: &mut Diagnostic, rcvr_ty: Ty<'tcx>) {
let ty::Adt(adt_def, _) = rcvr_ty.kind() else {
return;
};
let SelfSource::QPath(ty) = source else {
return;
};
let hir = self.tcx.hir();
if let Some(Node::Pat(_)) = hir.find(hir.parent_id(ty.hir_id)) {
// Do not suggest a fn call when a pattern is expected.
return;
}
let mut items = self
.tcx
.inherent_impls(adt_def.did())
@ -1504,7 +1478,7 @@ fn suggest_associated_call_syntax(
rcvr_ty: Ty<'tcx>,
source: SelfSource<'tcx>,
item_name: Ident,
args: Option<MethodCallComponents<'tcx>>,
args: Option<&'tcx [hir::Expr<'tcx>]>,
sugg_span: Span,
) {
let mut has_unsuggestable_args = false;
@ -1578,38 +1552,40 @@ fn suggest_associated_call_syntax(
None
};
let mut applicability = Applicability::MachineApplicable;
let args = if let Some(MethodCallComponents { receiver, args, .. }) = args {
// The first arg is the same kind as the receiver
let explicit_args = if first_arg.is_some() {
std::iter::once(receiver).chain(args.iter()).collect::<Vec<_>>()
let args = if let SelfSource::MethodCall(receiver) = source
&& let Some(args) = args
{
// The first arg is the same kind as the receiver
let explicit_args = if first_arg.is_some() {
std::iter::once(receiver).chain(args.iter()).collect::<Vec<_>>()
} else {
// There is no `Self` kind to infer the arguments from
if has_unsuggestable_args {
applicability = Applicability::HasPlaceholders;
}
args.iter().collect()
};
format!(
"({}{})",
first_arg.unwrap_or(""),
explicit_args
.iter()
.map(|arg| self
.tcx
.sess
.source_map()
.span_to_snippet(arg.span)
.unwrap_or_else(|_| {
applicability = Applicability::HasPlaceholders;
"_".to_owned()
}))
.collect::<Vec<_>>()
.join(", "),
)
} else {
// There is no `Self` kind to infer the arguments from
if has_unsuggestable_args {
applicability = Applicability::HasPlaceholders;
}
args.iter().collect()
applicability = Applicability::HasPlaceholders;
"(...)".to_owned()
};
format!(
"({}{})",
first_arg.unwrap_or(""),
explicit_args
.iter()
.map(|arg| self
.tcx
.sess
.source_map()
.span_to_snippet(arg.span)
.unwrap_or_else(|_| {
applicability = Applicability::HasPlaceholders;
"_".to_owned()
}))
.collect::<Vec<_>>()
.join(", "),
)
} else {
applicability = Applicability::HasPlaceholders;
"(...)".to_owned()
};
err.span_suggestion(
sugg_span,
"use associated function syntax instead",
@ -3267,56 +3243,59 @@ pub fn all_traits(tcx: TyCtxt<'_>) -> Vec<TraitInfo> {
}
fn print_disambiguation_help<'tcx>(
item_name: Ident,
args: Option<MethodCallComponents<'tcx>>,
tcx: TyCtxt<'tcx>,
err: &mut Diagnostic,
trait_name: String,
rcvr_ty: Ty<'_>,
impl_self_ty: Option<Ty<'_>>,
kind: ty::AssocKind,
def_kind_descr: &'static str,
source: SelfSource<'tcx>,
args: Option<&'tcx [hir::Expr<'tcx>]>,
trait_ref: ty::TraitRef<'tcx>,
candidate_idx: Option<usize>,
span: Span,
candidate: Option<usize>,
source_map: &source_map::SourceMap,
fn_has_self_parameter: bool,
item: ty::AssocItem,
) -> Option<String> {
let trait_ref = if item.fn_has_self_parameter {
trait_ref.print_only_trait_name().to_string()
} else {
format!("<{} as {}>", trait_ref.args[0], trait_ref.print_only_trait_name())
};
Some(
if let (ty::AssocKind::Fn, Some(MethodCallComponents { receiver, args, .. })) = (kind, args)
if matches!(item.kind, ty::AssocKind::Fn)
&& let SelfSource::MethodCall(receiver) = source
&& let Some(args) = args
{
let def_kind_descr = tcx.def_kind_descr(item.kind.as_def_kind(), item.def_id);
let item_name = item.ident(tcx);
let rcvr_ref = tcx.fn_sig(item.def_id).skip_binder().skip_binder().inputs()[0]
.ref_mutability()
.map_or("", |mutbl| mutbl.ref_prefix_str());
let args = format!(
"({}{})",
rcvr_ty.ref_mutability().map_or("", |mutbl| mutbl.ref_prefix_str()),
rcvr_ref,
std::iter::once(receiver)
.chain(args.iter())
.map(|arg| source_map
.map(|arg| tcx
.sess
.source_map()
.span_to_snippet(arg.span)
.unwrap_or_else(|_| { "_".to_owned() }))
.collect::<Vec<_>>()
.join(", "),
);
let trait_name = if !fn_has_self_parameter && let Some(impl_self_ty) = impl_self_ty {
format!("<{impl_self_ty} as {trait_name}>")
} else {
trait_name
};
err.span_suggestion_verbose(
span,
format!(
"disambiguate the {def_kind_descr} for {}",
if let Some(candidate) = candidate {
if let Some(candidate) = candidate_idx {
format!("candidate #{candidate}")
} else {
"the candidate".to_string()
},
),
format!("{trait_name}::{item_name}{args}"),
format!("{trait_ref}::{item_name}{args}"),
Applicability::HasPlaceholders,
);
return None;
} else if let Some(impl_self_ty) = impl_self_ty {
format!("<{impl_self_ty} as {trait_name}>::")
} else {
format!("{trait_name}::")
format!("{trait_ref}::")
},
)
}

View File

@ -166,9 +166,9 @@ pub(crate) fn check_pat_top(
fn check_pat(&self, pat: &'tcx Pat<'tcx>, expected: Ty<'tcx>, pat_info: PatInfo<'tcx, '_>) {
let PatInfo { binding_mode: def_bm, top_info: ti, .. } = pat_info;
let path_res = match &pat.kind {
PatKind::Path(qpath) => {
Some(self.resolve_ty_and_res_fully_qualified_call(qpath, pat.hir_id, pat.span))
}
PatKind::Path(qpath) => Some(
self.resolve_ty_and_res_fully_qualified_call(qpath, pat.hir_id, pat.span, None),
),
_ => None,
};
let adjust_mode = self.calc_adjust_mode(pat, path_res.map(|(res, ..)| res));
@ -1060,7 +1060,7 @@ fn check_pat_tuple_struct(
// Resolve the path and check the definition for errors.
let (res, opt_ty, segments) =
self.resolve_ty_and_res_fully_qualified_call(qpath, pat.hir_id, pat.span);
self.resolve_ty_and_res_fully_qualified_call(qpath, pat.hir_id, pat.span, None);
if res == Res::Err {
let e = tcx.sess.delay_span_bug(pat.span, "`Res::Err` but no error emitted");
self.set_tainted_by_errors(e);

View File

@ -29,10 +29,10 @@ LL | fn foo(&self) {}
| ^^^^^^^^^^^^^
help: use fully-qualified syntax to disambiguate
|
LL | <T as A>::foo(&s);
| ~~~~~~~~~~
LL | <T as B>::foo(&s);
| ~~~~~~~~~~
LL | A::foo(&s);
| ~~~
LL | B::foo(&s);
| ~~~
error[E0034]: multiple applicable items in scope
--> $DIR/disambiguate-multiple-blanket-impl.rs:33:8
@ -52,9 +52,9 @@ LL | const CONST: usize = 2;
| ^^^^^^^^^^^^^^^^^^
help: use fully-qualified syntax to disambiguate
|
LL | <T as A>::CONST;
LL | <S as A>::CONST;
| ~~~~~~~~~~
LL | <T as B>::CONST;
LL | <S as B>::CONST;
| ~~~~~~~~~~
error: aborting due to 3 previous errors

View File

@ -29,10 +29,10 @@ LL | fn foo(&self) {}
| ^^^^^^^^^^^^^
help: use fully-qualified syntax to disambiguate
|
LL | <S as A>::foo(&s);
| ~~~~~~~~~~
LL | <S as B>::foo(&s);
| ~~~~~~~~~~
LL | A::foo(&s);
| ~~~
LL | B::foo(&s);
| ~~~
error[E0034]: multiple applicable items in scope
--> $DIR/disambiguate-multiple-impl.rs:34:16

View File

@ -37,12 +37,12 @@ LL | fn foo(&self);
| ^^^^^^^^^^^^^^
help: disambiguate the method for candidate #1
|
LL | A::foo(t);
| ~~~~~~~~~
LL | A::foo(&t);
| ~~~~~~~~~~
help: disambiguate the method for candidate #2
|
LL | B::foo(t);
| ~~~~~~~~~
LL | B::foo(&t);
| ~~~~~~~~~~
error[E0034]: multiple applicable items in scope
--> $DIR/disambiguate-multiple-trait-2.rs:20:16
@ -62,10 +62,10 @@ LL | const CONST: usize;
| ^^^^^^^^^^^^^^^^^^
help: use fully-qualified syntax to disambiguate
|
LL | let _ = A::CONST;
| ~~~
LL | let _ = B::CONST;
| ~~~
LL | let _ = <T as A>::CONST;
| ~~~~~~~~~~
LL | let _ = <T as B>::CONST;
| ~~~~~~~~~~
error[E0223]: ambiguous associated type
--> $DIR/disambiguate-multiple-trait-2.rs:52:12
@ -98,10 +98,10 @@ LL | fn foo(&self) {}
| ^^^^^^^^^^^^^
help: use fully-qualified syntax to disambiguate
|
LL | <T as A>::foo(&s);
| ~~~~~~~~~~
LL | <T as B>::foo(&s);
| ~~~~~~~~~~
LL | A::foo(&s);
| ~~~
LL | B::foo(&s);
| ~~~
error[E0034]: multiple applicable items in scope
--> $DIR/disambiguate-multiple-trait-2.rs:49:16
@ -121,9 +121,9 @@ LL | const CONST: usize = 1;
| ^^^^^^^^^^^^^^^^^^
help: use fully-qualified syntax to disambiguate
|
LL | let _ = <T as A>::CONST;
LL | let _ = <S as A>::CONST;
| ~~~~~~~~~~
LL | let _ = <T as B>::CONST;
LL | let _ = <S as B>::CONST;
| ~~~~~~~~~~
error: aborting due to 6 previous errors

View File

@ -29,10 +29,10 @@ LL | fn foo(&self) {}
| ^^^^^^^^^^^^^
help: use fully-qualified syntax to disambiguate
|
LL | <T as A>::foo(&s);
| ~~~~~~~~~~
LL | <T as B>::foo(&s);
| ~~~~~~~~~~
LL | A::foo(&s);
| ~~~
LL | B::foo(&s);
| ~~~
error[E0034]: multiple applicable items in scope
--> $DIR/disambiguate-multiple-trait.rs:27:16
@ -52,9 +52,9 @@ LL | const CONST: usize = 2;
| ^^^^^^^^^^^^^^^^^^
help: use fully-qualified syntax to disambiguate
|
LL | let _ = <T as A>::CONST;
LL | let _ = <S as A>::CONST;
| ~~~~~~~~~~
LL | let _ = <T as B>::CONST;
LL | let _ = <S as B>::CONST;
| ~~~~~~~~~~
error: aborting due to 3 previous errors

View File

@ -16,12 +16,12 @@ LL | trait B { fn foo(&self); }
| ^^^^^^^^^^^^^^
help: disambiguate the method for candidate #1
|
LL | A::foo(t);
| ~~~~~~~~~
LL | A::foo(&t);
| ~~~~~~~~~~
help: disambiguate the method for candidate #2
|
LL | B::foo(t);
| ~~~~~~~~~
LL | B::foo(&t);
| ~~~~~~~~~~
error: aborting due to previous error

View File

@ -54,8 +54,8 @@ LL | let z = NuisanceFoo::foo(x);
| ~~~~~~~~~~~~~~~~~~~
help: disambiguate the method for candidate #3
|
LL | let z = FinalFoo::foo(x);
| ~~~~~~~~~~~~~~~~
LL | let z = FinalFoo::foo(&x);
| ~~~~~~~~~~~~~~~~~
error[E0308]: mismatched types
--> $DIR/method-deref-to-same-trait-object-with-separate-params.rs:139:24

View File

@ -16,12 +16,12 @@ LL | fn foo(&mut self) {}
| ^^^^^^^^^^^^^^^^^
help: disambiguate the method for candidate #1
|
LL | A::foo(&a)
| ~~~~~~~~~~
LL | A::foo(&mut a)
| ~~~~~~~~~~~~~~
help: disambiguate the method for candidate #2
|
LL | B::foo(&a)
| ~~~~~~~~~~
LL | B::foo(&mut a)
| ~~~~~~~~~~~~~~
error[E0034]: multiple applicable items in scope
--> $DIR/issue-37767.rs:22:7