import pytest import nltk.data def test_find_raises_exception(): with pytest.raises(LookupError): nltk.data.find("no_such_resource/foo") def test_find_raises_exception_with_full_resource_name(): no_such_thing = "no_such_thing/bar" with pytest.raises(LookupError) as exc: nltk.data.find(no_such_thing) assert no_such_thing in str(exc)