Fix a NPE bug.

[thomaskistler]

To address a potential NullPointerException (NPE), this fix handles cases where the flowSummary() method returns an empty result.

The code now explicitly checks for an empty result from flowSummary(). If an empty result is detected, an empty SensorFlowSummary object is created and returned instead.

[dknowles2]

Can you add a test for this?

[thomaskistler]

I added a test.

Also fixed an issue I ran into with the watering reports. It looks like Hydrawise does not strictly honor the start time and end time provided to the call. Hence we need to filter out events that happen before and after the provided time range. I updated the tests to cover this case as well.

[dknowles2]

Please split this into two PRs.

[dknowles2]

I think the way pytest intends you to do this is to use Indirect parametrization. Something like this:

@fixture
def flow_summary_json(param):
  if param:
    yield {"valid": "json"}
  else:
    yield None


@pytest.mark.parametrize("flow_summary_json", (True, False), indirect=True)
def test_get_water_flow_summary(..., flow_summary_json):
  ...
  mock_session.execute.return_value = {"controller": {"sensors": [flow_sensor_json | {"flowSummary": flow_summary_json}]}}

[thomaskistler]

Didn't know that. Thanks. Fixed.