def test_none_r(bs):
stream = bio(bs)
assert rw.none().read(stream) is None
stream.read() == 'a b c'
assert rw.none().width() == 0
def test_none_w():
stream = BytesIO()
assert rw.none().write(42, stream) == stream
assert stream.getvalue() == ''
def test_none_r(bs):
stream = bio(bs)
assert rw.none().read(stream) is None
stream.read() == 'a b c'
assert rw.none().width() == 0
def test_none_w():
stream = BytesIO()
assert rw.none().write(42, stream) == stream
assert stream.getvalue() == ''
@pytest.mark.parametrize('other, bs', [
(rw.none(), []),
(rw.number(1), [1]),
(rw.number(4), [1, 2, 3, 4]),
])
def test_constant_r(other, bs):
stream = bio(bs)
assert rw.constant(other, 42).read(stream) == 42
assert stream.read() == ''
assert rw.constant(other, 42).width() == other.width()
@pytest.mark.parametrize('other, v1, v2', [
(rw.none(), None, None),
(rw.number(1), 10, 12),
(rw.number(2), 500, 1),
