[TEST FAILURE] Flaky LazyLoaderRefreshFileMappingTest Test

[cianyleow]

Please paste the link from the specific build where the failure first started: This occurred in CI for a private fork of the salt repository, but is something that we felt would be useful upstream.

The error seen was related to a mismatch of an assertion between the number of calls to a function and the number of times a lock was acquired.

In our local CI environment, the threading.RLock.__enter__ function is called more often than the _refresh_file_mapping function, which leads to occasional failures (the full text of the issue is below).

tests/unit/test_loader.py:1722 (LazyLoaderRefreshFileMappingTest.test_lazyloader_refresh_file_mapping_called_with_lock_at___init__)
2 != 11

self = <tests.unit.test_loader.LazyLoaderRefreshFileMappingTest testMethod=test_lazyloader_refresh_file_mapping_called_with_lock_at___init__>

    def test_lazyloader_refresh_file_mapping_called_with_lock_at___init__(self):
        func_mock = MagicMock()
        lock_mock = MagicMock()
        lock_mock.__enter__ = MagicMock()
        self.LOADER_CLASS._refresh_file_mapping = func_mock
        with patch("threading.RLock", MagicMock(return_value=lock_mock)):
            loader = self.__init_loader()
        lock_mock.__enter__.assert_called()
        func_mock.assert_called()
>       assert len(func_mock.call_args_list) == len(lock_mock.__enter__.call_args_list)
E       AssertionError: assert 2 == 11
E        +  where 2 = len([call(), call()])
E        +    where [call(), call()] = <MagicMock id='140237436141920'>.call_args_list
E        +  and   11 = len([call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call()])
E        +    where [call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call(),\n call()] = <MagicMock name='mock.__enter__' id='140237435083984'>.call_args_list
E        +      where <MagicMock name='mock.__enter__' id='140237435083984'> = <MagicMock id='140237435272736'>.__enter__

tests/unit/test_loader.py:1732: AssertionError

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