'Test transform with a single word.'

@pytest.mark.parametrize('val,    expected', [('foobar', ['foobar']), ('foobar    baz', ['foobar', 'baz']), ('foo    "bar    baz"    fish', ['foo', 'bar    baz', 'fish']), ('', None)])
def test_transform_single(self, klass, val, expected):

    assert (klass().transform(val) == expected)
