More tests

src/test/ui/closures/supertrait-hint-cycle-2.rs

@@ -0,0 +1,18 @@
+// check-pass
+
+trait Foo<'a> {
+    type Input;
+}
+
+impl<F: Fn(u32)> Foo<'_> for F {
+    type Input = u32;
+}
+
+trait SuperFn: for<'a> Foo<'a> + for<'a> Fn(<Self as Foo<'a>>::Input) {}
+impl<T> SuperFn for T where T: for<'a> Fn(<Self as Foo<'a>>::Input) + for<'a> Foo<'a> {}
+
+fn needs_super(_: impl SuperFn) {}
+
+fn main() {
+    needs_super(|_: u32| {});
+}

src/test/ui/closures/supertrait-hint-cycle-3.rs

@@ -0,0 +1,16 @@
+// check-pass
+
+
+trait Foo<'a> {
+    type Input;
+}
+
+impl<F: Fn(u32)> Foo<'_> for F {
+    type Input = u32;
+}
+
+fn needs_super<F: for<'a> Fn(<F as Foo<'a>>::Input) + for<'a> Foo<'a>>(_: F) {}
+
+fn main() {
+    needs_super(|_: u32| {});
+}