1 files changed, 79 insertions, 0 deletions
diff --git a/src/test/ui/type-alias-impl-trait/type-alias-impl-trait.rs b/src/test/ui/type-alias-impl-trait/type-alias-impl-trait.rs
new file mode 100644
index 000000000..70c2ee427
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/type-alias-impl-trait.rs
@@ -0,0 +1,79 @@
+// check-pass
+
+#![allow(dead_code)]
+#![allow(unused_assignments)]
+#![allow(unused_variables)]
+#![feature(type_alias_impl_trait)]
+
+fn main() {
+    assert_eq!(foo().to_string(), "foo");
+    assert_eq!(bar1().to_string(), "bar1");
+    assert_eq!(bar2().to_string(), "bar2");
+    let mut x = bar1();
+    x = bar2();
+    assert_eq!(my_iter(42u8).collect::<Vec<u8>>(), vec![42u8]);
+}
+
+// single definition
+type Foo = impl std::fmt::Display;
+
+fn foo() -> Foo {
+    "foo"
+}
+
+// two definitions
+type Bar = impl std::fmt::Display;
+
+fn bar1() -> Bar {
+    "bar1"
+}
+
+fn bar2() -> Bar {
+    "bar2"
+}
+
+type MyIter<T> = impl Iterator<Item = T>;
+
+fn my_iter<T>(t: T) -> MyIter<T> {
+    std::iter::once(t)
+}
+
+fn my_iter2<T>(t: T) -> MyIter<T> {
+    std::iter::once(t)
+}
+
+// param names should not have an effect!
+fn my_iter3<U>(u: U) -> MyIter<U> {
+    std::iter::once(u)
+}
+
+// param position should not have an effect!
+fn my_iter4<U, V>(_: U, v: V) -> MyIter<V> {
+    std::iter::once(v)
+}
+
+// param names should not have an effect!
+type MyOtherIter<T> = impl Iterator<Item = T>;
+
+fn my_other_iter<U>(u: U) -> MyOtherIter<U> {
+    std::iter::once(u)
+}
+
+trait Trait {}
+type GenericBound<'a, T: Trait + 'a> = impl Sized + 'a;
+
+fn generic_bound<'a, T: Trait + 'a>(t: T) -> GenericBound<'a, T> {
+    t
+}
+
+mod pass_through {
+    pub type Passthrough<T: 'static> = impl Sized + 'static;
+
+    fn define_passthrough<T: 'static>(t: T) -> Passthrough<T> {
+        t
+    }
+}
+
+fn use_passthrough(x: pass_through::Passthrough<u32>) -> pass_through::Passthrough<u32> {
+    x
+}