1 files changed, 66 insertions, 0 deletions
diff --git a/src/test/ui/rfc-2027-object-safe-for-dispatch/manual-self-impl-for-unsafe-obj.rs b/src/test/ui/rfc-2027-object-safe-for-dispatch/manual-self-impl-for-unsafe-obj.rs
new file mode 100644
index 000000000..721890db4
--- /dev/null
+++ b/src/test/ui/rfc-2027-object-safe-for-dispatch/manual-self-impl-for-unsafe-obj.rs
@@ -0,0 +1,66 @@
+// Check that we can manually implement an object-unsafe trait for its trait object.
+
+// run-pass
+
+#![feature(object_safe_for_dispatch)]
+
+trait Bad {
+    fn stat() -> char {
+        'A'
+    }
+    fn virt(&self) -> char {
+        'B'
+    }
+    fn indirect(&self) -> char {
+        Self::stat()
+    }
+}
+
+trait Good {
+    fn good_virt(&self) -> char {
+        panic!()
+    }
+    fn good_indirect(&self) -> char {
+        panic!()
+    }
+}
+
+impl<'a> Bad for dyn Bad + 'a {
+    fn stat() -> char {
+        'C'
+    }
+    fn virt(&self) -> char {
+        'D'
+    }
+}
+
+struct Struct {}
+
+impl Bad for Struct {}
+
+impl Good for Struct {}
+
+fn main() {
+    let s = Struct {};
+
+    let mut res = String::new();
+
+    // Directly call static.
+    res.push(Struct::stat()); // "A"
+    res.push(<dyn Bad>::stat()); // "AC"
+
+    let good: &dyn Good = &s;
+
+    // These look similar enough...
+    let bad = unsafe { std::mem::transmute::<&dyn Good, &dyn Bad>(good) };
+
+    // Call virtual.
+    res.push(s.virt()); // "ACB"
+    res.push(bad.virt()); // "ACBD"
+
+    // Indirectly call static.
+    res.push(s.indirect()); // "ACBDA"
+    res.push(bad.indirect()); // "ACBDAC"
+
+    assert_eq!(&res, "ACBDAC");
+}