1 files changed, 29 insertions, 0 deletions
diff --git a/src/test/ui/duplicate/duplicate-type-parameter.rs b/src/test/ui/duplicate/duplicate-type-parameter.rs
new file mode 100644
index 000000000..2751b3c8d
--- /dev/null
+++ b/src/test/ui/duplicate/duplicate-type-parameter.rs
@@ -0,0 +1,29 @@
+type Foo<T,T> = Option<T>;
+//~^ ERROR the name `T` is already used
+
+struct Bar<T,T>(T);
+//~^ ERROR the name `T` is already used
+
+struct Baz<T,T> {
+//~^ ERROR the name `T` is already used
+    x: T,
+}
+
+enum Boo<T,T> {
+//~^ ERROR the name `T` is already used
+    A(T),
+    B,
+}
+
+fn quux<T,T>(x: T) {}
+//~^ ERROR the name `T` is already used
+
+trait Qux<T,T> {}
+//~^ ERROR the name `T` is already used
+
+impl<T,T> Qux<T,T> for Option<T> {}
+//~^ ERROR the name `T` is already used
+//~^^ ERROR the type parameter `T` is not constrained
+
+fn main() {
+}