Unittest Patch only works on attributes, methods

Bug report

Bug description:

I am having an issue where the patch method from the unittest.mock module is only working when I patch attributes of imported modules in other files. I do not understand if this is an issue of my import patterns or a misunderstanding of how patching works. (I am importing the app code before the patch is able to run).

I devised a test to show how the functionality is confusing me:

In my app code I have the following code

    from datetime import date
    ...
    import boto3
    ...
    from common.functions import asodates2datetime
    from core.mixins.usecases import ASOUsecaseTools


    class foo:
        @staticmethod
        @ASOUsecaseTools.get_by_name
        def bar(self, relevant_date):
            client = boto3.client("s3")
            today = date.today()
            date = asodates2datetime(relevant_date)

And from my test code I can patch in the following way:

    @mock.patch("src.aoi.usecases.date")
    @mock.patch("src.aoi.usecases.ASOUsecaseTools.get_by_name")
    @mock.patch("src.aoi.usecases.asodates2datetime")
    @mock.patch("src.aoi.usecases.boto3.client")
    def test_foo_gets_bar(self, m_d, m_g, m_a, m_c):
        m_d.today.return_value = <date>
        m_d.side_effect = lambda *args, **kw: date(*args, **kw)
        # more patching of functions here

However, when the test is run, If I set a breakpoint in the bar function and check the value of the patched items, only the patched methods show up as MagicMock

    >>> boto3.client
        <MagicMock name='client...>
    >>> ASOUsecaseTools.get_by_name
        <MagicMock name='get_by_name...>
    >>> asodates2datetime
        <function asodates2datetime...>
    >>> date
        <class 'datetime.date'>

The thing that confuses me is that I am patching along with how the docs say to patch: https://docs.python.org/3/library/unittest.mock-examples.html#partial-mocking

Also the fact that patched methods work but classes and functions don't indicates that the import structure is not a problem because the imported methods would be overwritten in the same way as the imported classes. It also indicates that the import paths are not incorrect; as the only difference between the patches is the type of object they are patching.

My current workaround is using the freeze package to freeze the date, but I prefer using builtin packages if possible.

CPython versions tested on:

3.9

Operating systems tested on:

macOS

Bắt đầu với trình tái hiện unittest.mock được cung cấp trong issue và so sánh các đích patch của nó với tài liệu partial mocking được liên kết. Xác minh hành vi trên CPython 3.9, sau đó xác định liệu khác biệt quan sát được có phải là một bug của interpreter có thể tái hiện hay là sự hiểu nhầm về import/patching; một test cụ thể bị lỗi và hành vi mong đợi sẽ xác định khi nào công việc được hoàn tất.