def test_removing_a_callback_multiple_times(self):
"""Guard against incorrect implementations which store their
callbacks in an array."""
input_ = InputCell(1)
output = ComputeCell([input_], lambda inputs: inputs[0] + 1)
cb1_observer, cb2_observer = [], []
callback1 = self.callback_factory(cb1_observer)
callback2 = self.callback_factory(cb2_observer)
output.add_callback(callback1)
output.add_callback(callback2)
output.remove_callback(callback1)
output.remove_callback(callback1)
output.remove_callback(callback1)
input_.value = 2
self.assertEqual(cb1_observer, [])
self.assertEqual(cb2_observer[-1], 3)
def test_removing_a_callback_multiple_times(self):
"""Guard against incorrect implementations which store their
callbacks in an array."""
input_ = InputCell(1)
output = ComputeCell([input_], lambda inputs: inputs[0] + 1)
cb1_observer, cb2_observer = [], []
callback1 = self.callback_factory(cb1_observer)
callback2 = self.callback_factory(cb2_observer)
output.add_callback(callback1)
output.add_callback(callback2)
output.remove_callback(callback1)
output.remove_callback(callback1)
output.remove_callback(callback1)
input_.value = 2
self.assertEqual(cb1_observer, [])
self.assertEqual(cb2_observer[-1], 3)
def test_callbacks_can_be_added_and_removed(self):
input_ = InputCell(11)
output = ComputeCell([input_], lambda inputs: inputs[0] + 1)
cb1_observer, cb2_observer, cb3_observer = [], [], []
callback1 = self.callback_factory(cb1_observer)
callback2 = self.callback_factory(cb2_observer)
callback3 = self.callback_factory(cb3_observer)
output.add_callback(callback1)
output.add_callback(callback2)
input_.value = 31
self.assertEqual(cb1_observer[-1], 32)
self.assertEqual(cb2_observer[-1], 32)
output.remove_callback(callback1)
output.add_callback(callback3)
input_.value = 41
self.assertEqual(cb2_observer[-1], 42)
self.assertEqual(cb3_observer[-1], 42)
# Expect callback1 not to be called.
self.assertEqual(len(cb1_observer), 1)
def test_callbacks_can_be_added_and_removed(self):
input_ = InputCell(11)
output = ComputeCell([input_], lambda inputs: inputs[0] + 1)
cb1_observer, cb2_observer, cb3_observer = [], [], []
callback1 = self.callback_factory(cb1_observer)
callback2 = self.callback_factory(cb2_observer)
callback3 = self.callback_factory(cb3_observer)
output.add_callback(callback1)
output.add_callback(callback2)
input_.value = 31
self.assertEqual(cb1_observer[-1], 32)
self.assertEqual(cb2_observer[-1], 32)
output.remove_callback(callback1)
output.add_callback(callback3)
input_.value = 41
self.assertEqual(cb2_observer[-1], 42)
self.assertEqual(cb3_observer[-1], 42)
# Expect callback1 not to be called.
self.assertEqual(len(cb1_observer), 1)
