pkg/front_end/testcases/extension_types/issue53791.dart.textual_outline.expect

class A {}

extension type E(Object? it) {}

typedef TA = A;

typedef TE = E;

extension type E1(A it) implements A, A {}

extension type E2(E it) implements E, E {}

extension type E3(A it) implements A, TA, A, TA {}

extension type E4(E it) implements E, TE, E, TE {}