def test_delegate_parameter_with_changed_source_snapshot_matches_value(
value, scale, offset):
delegate_param = DelegateParameter(name="delegate",
source=None,
scale=scale,
offset=offset)
source_parameter = Parameter(name="source",
get_cmd=None,
set_cmd=None,
initial_value=value)
_assert_none_source_is_correct(delegate_param)
delegate_param.source = source_parameter
calc_value = (value - offset) / scale
assert delegate_param.cache.get(get_if_invalid=False) == calc_value
assert delegate_param.source.cache.get(get_if_invalid=False) == value
snapshot = delegate_param.snapshot()
# disregard timestamp that might be slightly different
snapshot["source_parameter"].pop("ts")
source_snapshot = source_parameter.snapshot()
source_snapshot.pop("ts")
assert snapshot["source_parameter"] == source_snapshot
assert snapshot["value"] == calc_value
assert delegate_param.get() == calc_value
# now remove the source again
delegate_param.source = None
_assert_none_source_is_correct(delegate_param)
_assert_delegate_cache_none_source(delegate_param)
def test_delegate_parameter_change_source_reflected_in_label_and_unit():
delegate_param = DelegateParameter("delegate", source=None)
source_param_1 = Parameter("source1", label="source 1", unit="unit1")
source_param_2 = Parameter("source2", label="source 2", unit="unit2")
assert delegate_param.label == "delegate"
assert delegate_param.unit == ""
delegate_param.source = source_param_1
assert delegate_param.label == "source 1"
assert delegate_param.unit == "unit1"
delegate_param.source = source_param_2
assert delegate_param.label == "source 2"
assert delegate_param.unit == "unit2"
delegate_param.source = None
assert delegate_param.label == "delegate"
assert delegate_param.unit == ""
def test_delegate_parameter_get_and_snapshot_with_none_source():
"""
Test that a delegate parameter returns None on get and snapshot if
the source has a value of None and an offset or scale is used.
And returns a value if the source is remapped to a real parameter.
"""
none_param = Parameter("None")
source_param = Parameter('source',
get_cmd=None,
set_cmd=None,
initial_value=2)
delegate_param = DelegateParameter(name='delegate', source=none_param)
delegate_param.offset = 4
assert delegate_param.get() is None
assert delegate_param.snapshot()['value'] is None
delegate_param.offset = None
delegate_param.scale = 2
assert delegate_param.get() is None
assert delegate_param.snapshot()['value'] is None
assert delegate_param.cache._parameter.source.cache is none_param.cache
delegate_param.source = source_param
assert delegate_param.get() == 1
assert delegate_param.snapshot()['value'] == 1
assert delegate_param.cache._parameter.source.cache is source_param.cache
def test_delegate_parameter_fixed_label_unit_unchanged():
delegate_param = DelegateParameter("delegate",
label="delegatelabel",
unit="delegateunit",
source=None)
source_param_1 = Parameter("source1", label="source 1", unit="unit1")
source_param_2 = Parameter("source2", label="source 2", unit="unit2")
assert delegate_param.label == "delegatelabel"
assert delegate_param.unit == "delegateunit"
delegate_param.source = source_param_1
assert delegate_param.label == "delegatelabel"
assert delegate_param.unit == "delegateunit"
delegate_param.source = source_param_2
assert delegate_param.label == "delegatelabel"
assert delegate_param.unit == "delegateunit"
delegate_param.source = None
assert delegate_param.label == "delegatelabel"
assert delegate_param.unit == "delegateunit"
def test_gettable_settable_snapshotget_delegate_parameter_2(
gettable, get_cmd, settable, set_cmd, snapshot_value):
"""
Test that gettable/settable and snapshot_get are updated correctly
when source changes
"""
source_param = Parameter("source",
get_cmd=get_cmd,
set_cmd=set_cmd,
snapshot_value=snapshot_value)
delegate_param = DelegateParameter("delegate", source=None)
delegate_param.source = source_param
assert delegate_param.gettable is gettable
assert delegate_param.settable is settable
assert delegate_param._snapshot_value is snapshot_value
def test_delegate_parameter_get_and_snapshot_raises_with_none():
"""
Test that a delegate parameter raises on get and snapshot if
the source has a value of None and a scale is used.
But works correctly if the source is remapped to a real parameter.
"""
none_param = Parameter("None")
source_param = Parameter('source', get_cmd=None, set_cmd=None, initial_value=2)
delegate_param = DelegateParameter(name='delegate', source=none_param)
delegate_param.scale = 2
with pytest.raises(TypeError):
delegate_param.get()
with pytest.raises(TypeError):
delegate_param.snapshot()
assert delegate_param.cache._parameter.source.cache is none_param.cache
delegate_param.source = source_param
assert delegate_param.get() == 1
assert delegate_param.snapshot()['value'] == 1
assert delegate_param.cache._parameter.source.cache is source_param.cache
