bjoernager/rust
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For E0277 suggest adding Result return type for function which using QuesionMark ? in the body.

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This commit is contained in:
surechen 2024-06-09 17:20:25 +08:00
parent f3ff2f16c8
commit 0b3fec9388
7 changed files with 218 additions and 0 deletions
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41
compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
View file

@ -4586,6 +4586,47 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
_ => "/* value */".to_string(),
})
}
fn suggest_add_result_as_return_type(
&self,
obligation: &PredicateObligation<'tcx>,
err: &mut Diag<'_>,
trait_ref: ty::PolyTraitRef<'tcx>,
) {
if ObligationCauseCode::QuestionMark != *obligation.cause.code().peel_derives() {
return;
}
let node = self.tcx.hir_node_by_def_id(obligation.cause.body_id);
if let hir::Node::Item(item) = node
&& let hir::ItemKind::Fn(sig, _, body_id) = item.kind
&& let hir::FnRetTy::DefaultReturn(ret_span) = sig.decl.output
&& self.tcx.is_diagnostic_item(sym::FromResidual, trait_ref.def_id())
&& let ty::Tuple(l) = trait_ref.skip_binder().args.type_at(0).kind()
&& l.len() == 0
&& let ty::Adt(def, _) = trait_ref.skip_binder().args.type_at(1).kind()
&& self.tcx.is_diagnostic_item(sym::Result, def.did())
{
let body = self.tcx.hir().body(body_id);
let mut sugg_spans =
vec![(ret_span, " -> Result<(), Box<dyn std::error::Error>>".to_string())];
if let hir::ExprKind::Block(b, _) = body.value.kind
&& b.expr.is_none()
{
sugg_spans.push((
// The span will point to the closing curly brace `}` of the block.
b.span.shrink_to_hi().with_lo(b.span.hi() - BytePos(1)),
"\n Ok(())\n}".to_string(),
));
}
err.multipart_suggestion_verbose(
format!("consider adding return type"),
sugg_spans,
Applicability::MaybeIncorrect,
);
}
}
}
/// Add a hint to add a missing borrow or remove an unnecessary one.

4
compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
View file

@ -612,6 +612,10 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
&mut err,
trait_predicate,
);
self.suggest_add_result_as_return_type(&obligation,
&mut err,
trait_ref);
if self.suggest_add_reference_to_arg(
&obligation,
&mut err,