bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Remove unnecessary code and account for turbofish suggestion

Browse source 
Remove previously existing fallback that tried to give a good turbofish
suggestion, `need_type_info` is already good enough.

Special case `::<Vec<_>` suggestion for `Iterator::collect`.
This commit is contained in:
Esteban Küber 2022-12-10 12:19:29 -08:00
parent 9d5e7d3c04
commit b3fba5e18a
5 changed files with 43 additions and 87 deletions
Download patch file Download diff file Expand all files Collapse all files

58
compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
View file

@ -42,7 +42,7 @@ use rustc_middle::ty::{
};
use rustc_session::Limit;
use rustc_span::def_id::LOCAL_CRATE;
use rustc_span::symbol::{kw, sym};
use rustc_span::symbol::sym;
use rustc_span::{ExpnKind, Span, DUMMY_SP};
use std::fmt;
use std::iter;
@ -2198,60 +2198,10 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
}
}
if let ObligationCauseCode::ItemObligation(def_id) | ObligationCauseCode::ExprItemObligation(def_id, ..) = *obligation.cause.code() {
self.suggest_fully_qualified_path(&mut err, def_id, span, trait_ref.def_id());
} else if let Ok(snippet) = &self.tcx.sess.source_map().span_to_snippet(span)
&& let ObligationCauseCode::BindingObligation(def_id, _) | ObligationCauseCode::ExprBindingObligation(def_id, ..)
= *obligation.cause.code()
if let ObligationCauseCode::ItemObligation(def_id)
| ObligationCauseCode::ExprItemObligation(def_id, ..) = *obligation.cause.code()
{
let generics = self.tcx.generics_of(def_id);
if generics.params.iter().any(|p| p.name != kw::SelfUpper)
&& !snippet.ends_with('>')
&& !generics.has_impl_trait()
&& !self.tcx.is_fn_trait(def_id)
{
// FIXME: To avoid spurious suggestions in functions where type arguments
// where already supplied, we check the snippet to make sure it doesn't
// end with a turbofish. Ideally we would have access to a `PathSegment`
// instead. Otherwise we would produce the following output:
//
// error[E0283]: type annotations needed
// --> $DIR/issue-54954.rs:3:24
// |
// LL | const ARR_LEN: usize = Tt::const_val::<[i8; 123]>();
// | ^^^^^^^^^^^^^^^^^^^^^^^^^^
// | |
// | cannot infer type
// | help: consider specifying the type argument
// | in the function call:
// | `Tt::const_val::<[i8; 123]>::<T>`
// ...
// LL | const fn const_val<T: Sized>() -> usize {
// | - required by this bound in `Tt::const_val`
// |
// = note: cannot satisfy `_: Tt`
// Clear any more general suggestions in favor of our specific one
err.clear_suggestions();
err.span_suggestion_verbose(
span.shrink_to_hi(),
&format!(
"consider specifying the type argument{} in the function call",
pluralize!(generics.params.len()),
),
format!(
"::<{}>",
generics
.params
.iter()
.map(|p| p.name.to_string())
.collect::<Vec<String>>()
.join(", ")
),
Applicability::HasPlaceholders,
);
}
self.suggest_fully_qualified_path(&mut err, def_id, span, trait_ref.def_id());
}
if let (Some(body_id), Some(ty::subst::GenericArgKind::Type(_))) =