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Maze Tests

It's often hard to unit test graphical apps. It's not impossible, but it can be tricky. One strategy is to try to encapsulate any "pure" logic in its own functions so you can just unit test that logic without the drawing.

Assignment

Update the Window parameter to the Cell and Maze class to make it optional. It should default to None if not provided. Then update any methods that use the Window to check if it is None before trying to use it. If it's None, just skip any drawing (but still run the calculation logic).
Create a new tests.py file. We'll use the unittest package for our testing, so add the following to the top of tests.py:

import unittest

Import your Maze in the tests:

# assuming your `Maze` class is in a file called `maze.py`
from maze import Maze

Create a simple test:

class Tests(unittest.TestCase):
    def test_maze_create_cells(self):
        num_cols = 12
        num_rows = 10
        m1 = Maze(0, 0, num_rows, num_cols, 10, 10)
        self.assertEqual(
            len(m1._Maze__cells),
            num_cols,
        )
        self.assertEqual(
            len(m1._Maze__cells[0]),
            num_rows,
        )

Note the object._class__property syntax to access private properties outside the class. This is a result of Python's (feeble) attempt at hiding them through name mangling.

Add some code to make the tests run:

if __name__ == "__main__":
    unittest.main()

Run your tests, and make sure they work:

python3 tests.py

Add some more tests to make sure your maze constructor works under different conditions. You can do so by adding new methods to the Tests class. Your new tests should create a new maze but use different numbers of rows and columns. Use the assertEqual method again to check that everything worked.

Run and submit the CLI tests.