bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

review comments

Browse source
This commit is contained in:
Esteban Küber 2020-04-10 10:40:47 -07:00
commit ca25e2868d
1 changed files with 8 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

16
src/librustc_trait_selection/traits/error_reporting/suggestions.rs
View file

@ -175,7 +175,7 @@ fn suggest_restriction(
return;
}
// Given `fn foo(t: impl Trait)` where `Trait` requires assoc type `A`...
if let Some((name, fn_sig)) =
if let Some((bound_str, fn_sig)) =
fn_sig.zip(projection).and_then(|(sig, p)| match p.self_ty().kind {
// Shenanigans to get the `Trait` from the `impl Trait`.
ty::Param(param) => {
@ -194,14 +194,14 @@ fn suggest_restriction(
// but instead we choose to suggest replacing all instances of `impl Trait` with `T`
// where `T: Trait`.
let mut ty_spans = vec![];
let impl_name = format!("impl {}", name);
let impl_trait_str = format!("impl {}", bound_str);
for input in fn_sig.decl.inputs {
if let hir::TyKind::Path(hir::QPath::Resolved(
None,
hir::Path { segments: [segment], .. },
)) = input.kind
{
if segment.ident.as_str() == impl_name.as_str() {
if segment.ident.as_str() == impl_trait_str.as_str() {
// `fn foo(t: impl Trait)`
// ^^^^^^^^^^ get this to suggest `T` instead
@ -211,14 +211,14 @@ fn suggest_restriction(
}
}
let type_param_name = generics.params.next_type_param_name(Some(&name));
let type_param_name = generics.params.next_type_param_name(Some(&bound_str));
// The type param `T: Trait` we will suggest to introduce.
let type_param = format!("{}: {}", type_param_name, name);
let type_param = format!("{}: {}", type_param_name, bound_str);
// FIXME: modify the `trait_ref` instead of string shenanigans.
// Turn `<impl Trait as Foo>::Bar: Qux` into `<T as Foo>::Bar: Qux`.
let pred = trait_ref.without_const().to_predicate().to_string();
let pred = pred.replace(&impl_name, &type_param_name);
let pred = pred.replace(&impl_trait_str, &type_param_name);
let mut sugg = vec![
match generics
.params
@ -258,10 +258,10 @@ fn suggest_restriction(
);
} else {
// Trivial case: `T` needs an extra bound: `T: Bound`.
let (sp, s) =
let (sp, sugg) =
predicate_constraint(generics, trait_ref.without_const().to_predicate().to_string());
let appl = Applicability::MachineApplicable;
err.span_suggestion(sp, &format!("consider further restricting {}", msg), s, appl);
err.span_suggestion(sp, &format!("consider further restricting {}", msg), sugg, appl);
}
}