def test_issue3555(en_vocab):
    """Test that custom extensions with default None don't break matcher."""
    Token.set_extension("issue3555", default=None)
    matcher = Matcher(en_vocab)
    pattern = [{"ORTH": "have"}, {"_": {"issue3555": True}}]
    matcher.add("TEST", [pattern])
    doc = Doc(en_vocab, words=["have", "apple"])
    matcher(doc)
Test that custom extensions with default None don't break matcher.
spacy/tests/matcher/test_matcher_logic.py