Description

After PR #1844 comparison algorithm of python objects had been changed but comparison in state before / state after differences detector hadn't been. I fixed it.

Fixes #986

How to test

Manual tests

1. Write method which can change some class field or function which change one of the arguments. For example,

class A:
    def __init__(self, x: int):
        self.x = x
    def inc(self):  # test me 
        self.x += 1

or

def my_append(xs: list[int]):
    xs.append(1)

2. Generate tests
3. Expected: assertions for x-field and xs-argument have been created

class TestA(unittest.TestCase):
    def test_inc(self):
        a = copyreg._reconstructor(samples.arithmetic.A, builtins.object, None)
        a.x = -170141183460469231731687303715884105728
        actual = a.inc()
        self.assertEqual(None, actual)
        
        actual_x = a.x
        expected_x = a.x
        self.assertEqual(expected_x, actual_x)

and

class TestTopLevelFunctions(unittest.TestCase):
    def test_my_append(self):
        xs = [-170141183460469231731687303715884105728]
        actual = samples.arithmetic.my_append(xs)
        self.assertEqual(None, actual)

        self.assertEqual([-170141183460469231731687303715884105728, 1], xs)

Self-check list

Check off the item if the statement is true. Hint: [x] is a marked item.

Please do not delete the list or its items.

• I've set the proper labels for my PR (at least, for category and component).
• PR title and description are clear and intelligible.
• I've added enough comments to my code, particularly in hard-to-understand areas.
• The functionality I've repaired, changed or added is covered with automated tests.
• Manual tests have been provided optionally.
• The documentation for the functionality I've been working on is up-to-date.