async def test_stop_exposure_no_expose_running(self):
"""Test that stop_exposure does nothing if there is no active
`expose` command.
"""
spec = AvsFiberSpectrograph()
spec.stop_exposure()
self.patch.return_value.AVS_StopMeasure.assert_not_called()
async def test_stop_exposure(self):
"""Test that `stop_exposure` ends the active `expose`."""
duration = 5 # seconds
spec = AvsFiberSpectrograph()
t0 = time.monotonic()
task = asyncio.create_task(spec.expose(duration))
await asyncio.sleep(0.1) # give the event loop time to start
spec.stop_exposure()
with pytest.raises(asyncio.CancelledError):
await task
t1 = time.monotonic()
# cancelling the task should make it end much sooner than the duration
assert t1 - t0 < 1
self.patch.return_value.AVS_StopMeasure.assert_called_with(self.handle)
async def test_stop_exposure_during_poll_loop(self):
"""Test that `stop_exposure` ends the active `expose` when called
during the `PollData` loop.
"""
duration = 0.2 # seconds
# repeat "no data" forever, so that `stop` will trigger during polling
self.patch.return_value.AVS_PollScan.side_effect = itertools.repeat(0)
spec = AvsFiberSpectrograph()
task = asyncio.create_task(spec.expose(duration))
await asyncio.sleep(duration + 0.1
) # wait until we are in the poll loop
spec.stop_exposure()
with pytest.raises(asyncio.CancelledError):
await task
self.patch.return_value.AVS_StopMeasure.assert_called_with(self.handle)
self.patch.return_value.AVS_PollScan.assert_called_with(self.handle)
self.patch.return_value.AVS_GetScopeData.assert_not_called()
async def test_stop_exposure_fails(self):
"""Test `AVS_StopMeasure` returning an error: the existing exposure
task should be cancelled, but `stop_exposure` should also raise."""
duration = 5 # seconds
self.patch.return_value.AVS_StopMeasure.return_value = (
AvsReturnCode.ERR_TIMEOUT.value)
spec = AvsFiberSpectrograph()
t0 = time.monotonic()
task = asyncio.create_task(spec.expose(duration))
await asyncio.sleep(0.1) # give the event loop time to start
with pytest.raises(AvsReturnError, match="StopMeasure"):
spec.stop_exposure()
with pytest.raises(asyncio.CancelledError):
await task
t1 = time.monotonic()
# cancelling the task should make it end much sooner than the duration
assert t1 - t0 < 1
self.patch.return_value.AVS_StopMeasure.assert_called_with(self.handle)