Add comprehensive unit tests for PIRSensorHelper

[Ed0827]

Fixes #309

What was changed:

1. Added unit tests for the PIRSensorHelper in PIRSensorHelperTest.
2. Tests cover initialization logic, motion detection, and event listener management.
3. Edge cases such as an initially low sensor state, overriding event listeners, and multiple calls to removeEventListener have been verified.

Why was it changed:

1. To improve the reliability and maintainability of the PIRSensorHelper functionality.
2. Enhanced test coverage ensures that the sensor behavior is validated without needing actual hardware.
3. The changes help prevent regressions and simplify future development.

How was it changed:

1. Implemented tests using JUnit and Mockito to mock dependencies like DigitalInput and DigitalStateChangeListener.
2. The tests simulate sensor state changes to validate that 'isMoving' updates correctly.
3. Added tests to ensure that addEventListener properly overrides existing listeners and that multiple calls to removeEventListener are handled gracefully.

[yrlmanoharreddy]

The unit tests in PIRSensorHelperTest are well-structured, but the assertion messages can be improved for better clarity. For instance, instead of "Expected isMoving to be true when DigitalInput is high", use "Expected isMoving to be true when PIR sensor detects motion (DigitalInput is high)". This makes the test output more informative. Please update the assertion messages accordingly and push the changes. The rest of the implementation looks great! 👍

[avaenk]

Great job!

[avaenk]

Be sure this line does not cause any undefined behavior in your other tests, I tried a similar thing in my PR and noticed some strange behavior in my tests and ended up removing it. If it doesn't cause any issues feel free to keep.

[avaenk]

Maybe you could create one function for the test is moving instead of re-declaring the pirSensorHelper multiple times. It's possible to find a way to combine these functions into one, have the same functionality, and only have a few more lines of code.

[avaenk]

For our testing purposes I see why you use only two calls to the event listener, however, on your own time before re-committing the code ensure that 4-5 calls to the event listener causes no undefined behavior, two calls may not be enough to be sure.

[avaenk]

Love the use of ByteArrayOutputStream, awesome!