def test_pickling():
p = pickle.dumps(u.m)
other = pickle.loads(p)
assert other is u.m
new_unit = u.IrreducibleUnit(['foo'], format={'baz': 'bar'})
# This is local, so the unit should not be registered.
assert 'foo' not in u.get_current_unit_registry().registry
# Test pickling of this unregistered unit.
p = pickle.dumps(new_unit)
new_unit_copy = pickle.loads(p)
assert new_unit_copy.names == ['foo']
assert new_unit_copy.get_format_name('baz') == 'bar'
# It should still not be registered.
assert 'foo' not in u.get_current_unit_registry().registry
# Now try the same with a registered unit.
with u.add_enabled_units([new_unit]):
p = pickle.dumps(new_unit)
assert 'foo' in u.get_current_unit_registry().registry
# Check that a registered unit can be loaded and that it gets re-enabled.
with u.add_enabled_units([]):
assert 'foo' not in u.get_current_unit_registry().registry
new_unit_copy = pickle.loads(p)
assert new_unit_copy.names == ['foo']
assert new_unit_copy.get_format_name('baz') == 'bar'
assert 'foo' in u.get_current_unit_registry().registry
# And just to be sure, that it gets removed outside of the context.
assert 'foo' not in u.get_current_unit_registry().registry
hash_m = hash(u.m)
unit = pickle.loads(
b'\x80\x04\x95\xd6\x00\x00\x00\x00\x00\x00\x00\x8c\x12'
b'astropy.units.core\x94\x8c\x1a_recreate_irreducible_unit'
b'\x94\x93\x94h\x00\x8c\x0fIrreducibleUnit\x94\x93\x94]\x94'
b'(\x8c\x01m\x94\x8c\x05meter\x94e\x88\x87\x94R\x94}\x94(\x8c\x06'
b'_names\x94]\x94(h\x06h\x07e\x8c\x0c_short_names'
b'\x94]\x94h\x06a\x8c\x0b_long_names\x94]\x94h\x07a\x8c\x07'
b'_format\x94}\x94\x8c\x07__doc__\x94\x8c '
b'meter: base unit of length in SI\x94ub.')
assert unit is u.m
assert hash(u.m) == hash_m
@pytest.mark.parametrize('unit', [
u.IrreducibleUnit(['foo'], format={'baz': 'bar'}),
u.Unit('m_per_s', u.m / u.s)
])
def test_pickle_does_not_keep_memoized_hash(unit):
"""
Tests private attribute since the problem with _hash being pickled
and restored only appeared if the unpickling was done in another
session, for which the hash no longer was valid, and it is difficult
to mimic separate sessions in a simple test. See gh-11872.
"""
unit_hash = hash(unit)
assert unit._hash is not None
unit_copy = pickle.loads(pickle.dumps(unit))
# unit is not registered so we get a copy.
assert unit_copy is not unit
assert unit_copy._hash is None