From ac4f3e61f8c56dbe245e3ece0f2c38e17c3e199e Mon Sep 17 00:00:00 2001
From: Florian Diebold <flodiebold@gmail.com>
Date: Thu, 5 Aug 2021 22:44:38 +0200
Subject: [PATCH] Fix binders with bare dyn trait
Fixes #9639.
---
crates/hir_ty/src/lower.rs | 20 +++++++++-----------
crates/hir_ty/src/tests/regression.rs | 16 ++++++++++++++++
2 files changed, 25 insertions(+), 11 deletions(-)
diff --git a/crates/hir_ty/src/lower.rs b/crates/hir_ty/src/lower.rs
index 92b376c4402..5ba66fda8f8 100644
--- a/crates/hir_ty/src/lower.rs
+++ b/crates/hir_ty/src/lower.rs
@@ -401,18 +401,9 @@ impl<'a> TyLoweringContext<'a> {
) -> (Ty, Option<TypeNs>) {
let ty = match resolution {
TypeNs::TraitId(trait_) => {
- // if this is a bare dyn Trait, we'll directly put the required ^0 for the self type in there
- let self_ty = if remaining_segments.len() == 0 {
- Some(
- TyKind::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, 0))
- .intern(&Interner),
- )
- } else {
- None
- };
- let trait_ref =
- self.lower_trait_ref_from_resolved_path(trait_, resolved_segment, self_ty);
let ty = if remaining_segments.len() == 1 {
+ let trait_ref =
+ self.lower_trait_ref_from_resolved_path(trait_, resolved_segment, None);
let segment = remaining_segments.first().unwrap();
let found = self
.db
@@ -436,6 +427,13 @@ impl<'a> TyLoweringContext<'a> {
// FIXME report error (ambiguous associated type)
TyKind::Error.intern(&Interner)
} else {
+ let self_ty = Some(
+ TyKind::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, 0))
+ .intern(&Interner),
+ );
+ let trait_ref = self.with_shifted_in(DebruijnIndex::ONE, |ctx| {
+ ctx.lower_trait_ref_from_resolved_path(trait_, resolved_segment, self_ty)
+ });
let dyn_ty = DynTy {
bounds: crate::make_only_type_binders(
1,
diff --git a/crates/hir_ty/src/tests/regression.rs b/crates/hir_ty/src/tests/regression.rs
index 1e40ff24e3a..58bbaa1c80e 100644
--- a/crates/hir_ty/src/tests/regression.rs
+++ b/crates/hir_ty/src/tests/regression.rs
@@ -1077,3 +1077,19 @@ fn test() {
"#,
)
}
+
+#[test]
+fn bare_dyn_trait_binders_9639() {
+ check_no_mismatches(
+ r#"
+//- minicore: fn, coerce_unsized
+fn infix_parse<T, S>(_state: S, _level_code: &Fn(S)) -> T {
+ loop {}
+}
+
+fn parse_arule() {
+ infix_parse((), &(|_recurse| ()))
+}
+ "#,
+ )
+}