1 files changed, 36 insertions, 0 deletions
diff --git a/tests/try_join.rs b/tests/try_join.rs
new file mode 100644
index 0000000..6c6d084
--- /dev/null
+++ b/tests/try_join.rs
@@ -0,0 +1,36 @@
+#![deny(unreachable_code)]
+
+use futures::{try_join, executor::block_on};
+
+// TODO: This abuses https://github.com/rust-lang/rust/issues/58733 in order to
+// test behaviour of the `try_join!` macro with the never type before it is
+// stabilized. Once `!` is again stabilized this can be removed and replaced
+// with direct use of `!` below where `Never` is used.
+trait MyTrait {
+    type Output;
+}
+impl<T> MyTrait for fn() -> T {
+    type Output = T;
+}
+type Never = <fn() -> ! as MyTrait>::Output;
+
+
+#[test]
+fn try_join_never_error() {
+    block_on(async {
+        let future1 = async { Ok::<(), Never>(()) };
+        let future2 = async { Ok::<(), Never>(()) };
+        try_join!(future1, future2)
+    })
+    .unwrap();
+}
+
+#[test]
+fn try_join_never_ok() {
+    block_on(async {
+        let future1 = async { Err::<Never, ()>(()) };
+        let future2 = async { Err::<Never, ()>(()) };
+        try_join!(future1, future2)
+    })
+    .unwrap_err();
+}