1 files changed, 77 insertions, 0 deletions
diff --git a/tests/ui/consts/fn_trait_refs.rs b/tests/ui/consts/fn_trait_refs.rs
new file mode 100644
index 00000000000..b507492970a
--- /dev/null
+++ b/tests/ui/consts/fn_trait_refs.rs
@@ -0,0 +1,77 @@
+// check-pass
+
+#![feature(const_fn_trait_ref_impls)]
+#![feature(fn_traits)]
+#![feature(unboxed_closures)]
+#![feature(const_trait_impl)]
+#![feature(const_mut_refs)]
+#![feature(const_cmp)]
+#![feature(const_refs_to_cell)]
+
+use std::marker::Destruct;
+
+const fn tester_fn<T>(f: T) -> T::Output
+where
+    T: ~const Fn<()> + ~const Destruct,
+{
+    f()
+}
+
+const fn tester_fn_mut<T>(mut f: T) -> T::Output
+where
+    T: ~const FnMut<()> + ~const Destruct,
+{
+    f()
+}
+
+const fn tester_fn_once<T>(f: T) -> T::Output
+where
+    T: ~const FnOnce<()>,
+{
+    f()
+}
+
+const fn test_fn<T>(mut f: T) -> (T::Output, T::Output, T::Output)
+where
+    T: ~const Fn<()> + ~const Destruct,
+{
+    (
+        // impl<A: Tuple, F: ~const Fn + ?Sized> const Fn<A> for &F
+        tester_fn(&f),
+        // impl<A: Tuple, F: ~const Fn + ?Sized> const FnMut<A> for &F
+        tester_fn_mut(&f),
+        // impl<A: Tuple, F: ~const Fn + ?Sized> const FnOnce<A> for &F
+        tester_fn_once(&f),
+    )
+}
+
+const fn test_fn_mut<T>(mut f: T) -> (T::Output, T::Output)
+where
+    T: ~const FnMut<()> + ~const Destruct,
+{
+    (
+        // impl<A: Tuple, F: ~const FnMut + ?Sized> const FnMut<A> for &mut F
+        tester_fn_mut(&mut f),
+        // impl<A: Tuple, F: ~const FnMut + ?Sized> const FnOnce<A> for &mut F
+        tester_fn_once(&mut f),
+    )
+}
+const fn test(i: i32) -> i32 {
+    i + 1
+}
+
+fn main() {
+    const fn one() -> i32 {
+        1
+    };
+    const fn two() -> i32 {
+        2
+    };
+    const _: () = {
+        let test_one = test_fn(one);
+        assert!(test_one == (1, 1, 1));
+
+        let test_two = test_fn_mut(two);
+        assert!(test_two == (2, 2));
+    };
+}