#!/usr/bin/env python
#
# Author: Mike McKerns (mmckerns @caltech and @uqfoundation)
# Copyright (c) 2008-2016 California Institute of Technology.
# Copyright (c) 2016-2023 The Uncertainty Quantification Foundation.
# License: 3-clause BSD.  The full license text is available at:
#  - https://github.com/uqfoundation/dill/blob/master/LICENSE

from dill import __diff as diff

import sys
IS_PYPY = not hasattr(sys, 'getrefcount')

class A:
    pass

def test_diff():
    a = A()
    b = A()
    c = A()
    a.a = b
    b.a = c
    diff.memorise(a)
    assert not diff.has_changed(a)
    c.a = 1
    assert diff.has_changed(a)
    diff.memorise(c, force=True)
    assert not diff.has_changed(a)
    c.a = 2
    assert diff.has_changed(a)
    changed = diff.whats_changed(a)
    assert list(changed[0].keys()) == ["a"]
    assert not changed[1]

    a2 = []
    b2 = [a2]
    c2 = [b2]
    diff.memorise(c2)
    assert not diff.has_changed(c2)
    a2.append(1)
    assert diff.has_changed(c2)
    changed = diff.whats_changed(c2)
    assert changed[0] == {}
    assert changed[1]

    a3 = {}
    b3 = {1: a3}
    c3 = {1: b3}
    diff.memorise(c3)
    assert not diff.has_changed(c3)
    a3[1] = 1
    assert diff.has_changed(c3)
    changed = diff.whats_changed(c3)
    assert changed[0] == {}
    assert changed[1]

    if not IS_PYPY:
        import abc
        # make sure the "_abc_invaldation_counter" doesn't make test fail
        diff.memorise(abc.ABCMeta, force=True)
        assert not diff.has_changed(abc)
        abc.ABCMeta.zzz = 1
        assert diff.has_changed(abc)
        changed = diff.whats_changed(abc)
        assert list(changed[0].keys()) == ["ABCMeta"]
        assert not changed[1]

    '''
    import Queue
    diff.memorise(Queue, force=True)
    assert not diff.has_changed(Queue)
    Queue.Queue.zzz = 1
    assert diff.has_changed(Queue)
    changed = diff.whats_changed(Queue)
    assert list(changed[0].keys()) == ["Queue"]
    assert not changed[1]

    import math
    diff.memorise(math, force=True)
    assert not diff.has_changed(math)
    math.zzz = 1
    assert diff.has_changed(math)
    changed = diff.whats_changed(math)
    assert list(changed[0].keys()) == ["zzz"]
    assert not changed[1]
    '''

    a = A()
    b = A()
    c = A()
    a.a = b
    b.a = c
    diff.memorise(a)
    assert not diff.has_changed(a)
    c.a = 1
    assert diff.has_changed(a)
    diff.memorise(c, force=True)
    assert not diff.has_changed(a)
    del c.a
    assert diff.has_changed(a)
    changed = diff.whats_changed(a)
    assert list(changed[0].keys()) == ["a"]
    assert not changed[1]


if __name__ == '__main__':
    test_diff()
