From 4788aaa5f07da85707b7bf409b5d25df1682a760 Mon Sep 17 00:00:00 2001
From: Florian Diebold <flodiebold@gmail.com>
Date: Sun, 13 Dec 2020 14:52:45 +0100
Subject: [PATCH] Add test for #6852
---
crates/hir_ty/src/tests/regression.rs | 37 +++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/crates/hir_ty/src/tests/regression.rs b/crates/hir_ty/src/tests/regression.rs
index 8cf4e701240..da817041704 100644
--- a/crates/hir_ty/src/tests/regression.rs
+++ b/crates/hir_ty/src/tests/regression.rs
@@ -883,3 +883,40 @@ fn issue_6628() {
"#]],
);
}
+
+#[test]
+fn issue_6852() {
+ check_infer(
+ r#"
+ #[lang = "deref"]
+ pub trait Deref {
+ type Target;
+ }
+
+ struct BufWriter {}
+
+ struct Mutex<T> {}
+ struct MutexGuard<'a, T> {}
+ impl<T> Mutex<T> {
+ fn lock(&self) -> MutexGuard<'_, T> {}
+ }
+ impl<'a, T: 'a> Deref for MutexGuard<'a, T> {
+ type Target = T;
+ }
+ fn flush(&self) {
+ let w: &Mutex<BufWriter>;
+ *(w.lock());
+ }
+ "#,
+ expect![[r#"
+ 156..160 'self': &Mutex<T>
+ 183..185 '{}': ()
+ 267..271 'self': &{unknown}
+ 273..323 '{ ...()); }': ()
+ 283..284 'w': &Mutex<BufWriter>
+ 309..320 '*(w.lock())': BufWriter
+ 311..312 'w': &Mutex<BufWriter>
+ 311..319 'w.lock()': MutexGuard<BufWriter>
+ "#]],
+ );
+}