1 files changed, 79 insertions, 0 deletions
diff --git a/tests/ui/deref/pin-deref-const.rs b/tests/ui/deref/pin-deref-const.rs
new file mode 100644
index 00000000000..6ed00177b23
--- /dev/null
+++ b/tests/ui/deref/pin-deref-const.rs
@@ -0,0 +1,79 @@
+// The purpose of this file is to track the error messages from Pin and DerefMut interacting.
+//
+// Identical to `pin-deref.rs` except for using unstable `const fn`.
+
+//@ check-fail
+
+#![feature(const_convert)]
+#![feature(const_trait_impl)]
+
+use std::ops::DerefMut;
+use std::pin::Pin;
+
+struct MyUnpinType {}
+
+impl MyUnpinType {
+    const fn at_self(&self) {}
+    const fn at_mut_self(&mut self) {}
+}
+
+struct MyPinType(core::marker::PhantomPinned);
+
+impl MyPinType {
+    const fn at_self(&self) {}
+    const fn at_mut_self(&mut self) {}
+}
+
+const fn call_mut_ref_unpin(mut r_unpin: Pin<&mut MyUnpinType>) {
+    r_unpin.at_self();
+    r_unpin.at_mut_self();
+}
+
+const fn call_ref_unpin(mut r_unpin: Pin<&MyUnpinType>) {
+    r_unpin.at_self();
+    r_unpin.at_mut_self(); //~ ERROR: cannot borrow data in dereference of `Pin<&MyUnpinType>` as mutable
+}
+
+const fn call_mut_ref_pin(mut r_pin: Pin<&mut MyPinType>) {
+    r_pin.at_self();
+    r_pin.at_mut_self(); //~ ERROR: cannot borrow data in dereference of `Pin<&mut MyPinType>` as mutable
+}
+
+const fn call_ref_pin(mut r_pin: Pin<&MyPinType>) {
+    r_pin.at_self();
+    r_pin.at_mut_self(); //~ ERROR: cannot borrow data in dereference of `Pin<&MyPinType>` as mutable
+}
+
+const fn coerce_unpin_rr<'a>(mut r_unpin: &'a mut Pin<&MyUnpinType>) -> &'a MyUnpinType {
+    r_unpin
+}
+
+const fn coerce_unpin_rm<'a>(mut r_unpin: &'a mut Pin<&MyUnpinType>) -> &'a mut MyUnpinType {
+    r_unpin //~ ERROR: cannot borrow data in dereference of `Pin<&MyUnpinType>` as mutable
+}
+
+const fn coerce_unpin_mr<'a>(mut r_unpin: &'a mut Pin<&mut MyUnpinType>) -> &'a MyUnpinType {
+    r_unpin
+}
+
+const fn coerce_unpin_mm<'a>(mut r_unpin: &'a mut Pin<&mut MyUnpinType>) -> &'a mut MyUnpinType {
+    r_unpin
+}
+
+const fn coerce_pin_rr<'a>(mut r_pin: &'a mut Pin<&MyPinType>) -> &'a MyPinType {
+    r_pin
+}
+
+const fn coerce_pin_rm<'a>(mut r_pin: &'a mut Pin<&MyPinType>) -> &'a mut MyPinType {
+    r_pin //~ ERROR: cannot borrow data in dereference of `Pin<&MyPinType>` as mutable
+}
+
+const fn coerce_pin_mr<'a>(mut r_pin: &'a mut Pin<&mut MyPinType>) -> &'a MyPinType {
+    r_pin
+}
+
+const fn coerce_pin_mm<'a>(mut r_pin: &'a mut Pin<&mut MyPinType>) -> &'a mut MyPinType {
+    r_pin //~ ERROR: cannot borrow data in dereference of `Pin<&mut MyPinType>` as mutable
+}
+
+fn main() {}