pkg/front_end/testcases/extension_types/issue54625.dart.textual_outline.expect

void cfeAwait<XF extends F>(XF xf) async {}

extension type F(Future<int> _) implements Future<int> {}

void main() {}

extension Est<T> on T {
  void st<X extends E<T>>() {}
}

typedef E<S> = S Function(S);