gecko-dev/dom/bindings/parser/tests/test_incomplete_parent.py

import WebIDL

def WebIDLTest(parser, harness):
    parser.parse("""
        interface TestIncompleteParent : NotYetDefined {
          void foo();
        };

        interface NotYetDefined : EvenHigherOnTheChain {
        };

        interface EvenHigherOnTheChain {
        };
    """)

    parser.finish()

    harness.ok(True, "TestIncompleteParent interface parsed without error.")