def test_dictionary(value, width, pairs, bs):
assert rw.dictionary(*pairs).read(bio(bs)) == value
assert rw.dictionary(*pairs).write(
value, BytesIO()
).getvalue() == bytearray(bs)
assert rw.dictionary(*pairs).width() == width
def test_dictionary_read_error():
some_rw = InstanceDouble('tchannel.rw.ReadWriter')
allow(some_rw).read.and_raise(ReadError('great sadness'))
dict_rw = rw.dictionary(('foo', some_rw))
with pytest.raises(ReadError):
dict_rw.read(BytesIO())
def test_dictionary_ignore_fields():
d_rw = rw.dictionary(
('x', rw.number(1)),
(rw.skip, rw.constant(rw.number(2), 42)),
)
assert d_rw.read(bio([1, 0, 2])) == {'x': 1}
assert d_rw.write(
{'x': 1, rw.skip: 2, 'y': 3}, BytesIO()
).getvalue() == bytearray([1, 0, 42])
assert d_rw.width() == 3