def test_clan(self):
flags = Flags()
flags.f.clan = CacheStatus.IS_NOT
bitfields = Flags(asint=flags.asint).f
self.assertEqual(bitfields.clan, CacheStatus.IS_NOT)
bitfields.clan = CacheStatus.IS_NOT # No change = no problem
for state in [CacheStatus.UNKNOWN, CacheStatus.IS, CacheStatus.N_A]:
self.assertRaises(AssertionError, lambda: setattr(bitfields, 'clan', state))
def test_clan(self):
flags = Flags()
flags.f.clan = CacheStatus.IS_NOT
bitfields = Flags(asint=flags.asint).f
self.assertEqual(bitfields.clan, CacheStatus.IS_NOT)
bitfields.clan = CacheStatus.IS_NOT # No change = no problem
for state in [CacheStatus.UNKNOWN, CacheStatus.IS, CacheStatus.N_A]:
self.assertRaises(AssertionError, lambda: setattr(bitfields, 'clan', state))
def test_relation(self):
flags = Flags()
bitfields = flags.f
bitfields.relation = CacheStatus.IS
self.assertEqual(bitfields.relation, CacheStatus.IS)
flags_init = Flags(asint=flags.asint)
bitfields_init = flags_init.f
self.assertEqual(bitfields_init.relation, CacheStatus.IS)
bitfields.relation = CacheStatus.IS # No change = no problem
bitfields_init.relation = CacheStatus.IS # No change = no problem
for state in [CacheStatus.UNKNOWN, CacheStatus.IS_NOT, CacheStatus.N_A]:
self.assertRaises(AssertionError, lambda: setattr(bitfields_init, 'relation', state))
for state in [CacheStatus.UNKNOWN, CacheStatus.IS_NOT, CacheStatus.N_A]:
self.assertRaises(AssertionError, lambda: setattr(bitfields, 'relation', state))
def test_initial(self):
union = Flags()
self.assertEqual(len(union._fields_), 2)
flags = union.f
asint = union.asint
self.assertLessEqual(len(flags._fields_), SIZE_IN_BITS / 2) # 2 bits per bitfield.
self.assertTrue(isinstance(asint, int))
self.assertLessEqual(asint.bit_length(), SIZE_IN_BITS)
for field_name, field_type, field_size in flags._fields_:
self.assertEqual(field_type, c_uint8)
self.assertEqual(field_size, 2)
self.assertEqual(getattr(flags, field_name), 0)
def test_speed(self):
# The relation property is enum-based and uses a setter helper function.
# The clan property is int-based and uses a setter helper function.
# The multiclan property is int-based and has the code of the setter helper function
# directly in the setter.
#
# The approximate run times are (for 1e6 instances):
# rel (enum w/) clan (int w/) multiclan (int w/o)
# set 6.4 s 0.8 s 0.7 s
# get 5.3 s 1.5 s 1.5 s
#
# The performance difference (for int-based implementations) between using a setter helper
# (clan) and not using it (multiclan) is minimal, and setting is rare, so I decided to
# use a setter helper function. The performance difference between enum- and int-based
# implementations (rel and clan) seems to be more relevant, especially since there is
# also a hit when reading (the more frequent operation). So I decided not to use enums in
# this interface.
# NOTE: The actual code is not anymore like described above. In order to re-run this test,
# the code from here must be used in _flags.py:
#
# class State(_enum.Enum):
# UNKNOWN = 0
# IS = 1
# IS_NOT = 2
# N_A = 3
#
# @staticmethod
# def _setter_helper_enum(flags, value: State) -> int:
# int_val = value.value
# assert flags == State.UNKNOWN.value or flags == int_val
# assert 0 <= int_val <= 3
# return int_val
#
# @property
# def relation(self) -> State:
# return State(self._relation)
#
# @relation.setter
# def relation(self, value: State):
# self._relation = self._setter_helper_enum(self._relation, value)
#
# @multiclan.setter
# def multiclan(self, value: int):
# assert self._multiclan == CacheStatus.UNKNOWN or self._multiclan == value
# assert 0 <= value <= 3
# self._multiclan = value
if False:
# noinspection PyUnusedLocal
flags = [Flags() for i in range(1000000)]
# Commented out because of missing enum State.
# def time_rels():
# # Using an enum-based interface with a setter helper function.
# t1 = time.process_time()
# for flag in flags:
# flag.f.relation = State.IS_NOT
# t2 = time.process_time()
# for flag in flags:
# self.assertEqual(flag.f.relation, State.IS_NOT)
# t3 = time.process_time()
# for flag in flags:
# self.assertEqual(flag.f.relation, State.IS_NOT)
# t4 = time.process_time()
# print('set', t2 - t1)
# print('read1', t3 - t2)
# print('read2', t4 - t3)
# print('rels (enum w/)', t4 - t1, '\n')
def time_clans():
# Using an int-based interface with a setter helper function.
t1 = time.process_time()
for flag in flags:
flag.f.clan = CacheStatus.IS_NOT
t2 = time.process_time()
for flag in flags:
self.assertEqual(flag.f.clan, CacheStatus.IS_NOT)
t3 = time.process_time()
for flag in flags:
self.assertEqual(flag.f.clan, CacheStatus.IS_NOT)
t4 = time.process_time()
print('set', t2 - t1)
print('read1', t3 - t2)
print('read2', t4 - t3)
print('clans (int w/)', t4 - t1, '\n')
def time_multiclans():
# Using an int-based interface without a setter helper function.
t1 = time.process_time()
for flag in flags:
flag.f.multiclan = CacheStatus.IS_NOT
t2 = time.process_time()
for flag in flags:
self.assertEqual(flag.f.multiclan, CacheStatus.IS_NOT)
t3 = time.process_time()
for flag in flags:
self.assertEqual(flag.f.multiclan, CacheStatus.IS_NOT)
t4 = time.process_time()
print('set', t2 - t1)
print('read1', t3 - t2)
print('read2', t4 - t3)
print('multiclans (int w/o)', t4 - t1, '\n')
# time_rels()
time_clans()
time_multiclans()
# time_rels()
time_clans()
time_multiclans()
# time_rels()
time_clans()
time_multiclans()