我们可以使用pytest-mock (https://pypi.org/project/pytest-mock/)模拟器对象来模拟特定模块中的日期时间行为

假设您想在以下文件中模拟日期时间

# File path - source_dir/x/a.py
import datetime

def name_function():
     name = datetime.now()
     return f"name_{name}"

在测试函数中，mock将在测试运行时添加到函数中

def test_name_function(mocker):
     mocker.patch('x.a.datetime')
     x.a.datetime.now.return_value = datetime(2019, 1, 1)

     actual = name_function()

     assert actual == "name_2019-01-01"

我通过将datetime导入为realdatetime并将我在模拟中需要的方法替换为实际方法来完成这项工作:

import datetime as realdatetime

@mock.patch('datetime')
def test_method(self, mock_datetime):
    mock_datetime.today = realdatetime.today
    mock_datetime.now.return_value = realdatetime.datetime(2019, 8, 23, 14, 34, 8, 0)

我想我来晚了一点，但我认为这里的主要问题是您直接修补datetime.date.today，根据文档，这是错误的。

例如，您应该修补在测试函数所在的文件中导入的引用。

假设你有一个functions.py文件，其中包含以下内容:

import datetime

def get_today():
    return datetime.date.today()

然后，在你的测试中，你应该有这样的东西

import datetime
import unittest

from functions import get_today
from mock import patch, Mock

class GetTodayTest(unittest.TestCase):

    @patch('functions.datetime')
    def test_get_today(self, datetime_mock):
        datetime_mock.date.today = Mock(return_value=datetime.strptime('Jun 1 2005', '%b %d %Y'))
        value = get_today()
        # then assert your thing...

希望这能对你有所帮助。

也许您可以使用自己的“today()”方法，在需要的地方打补丁。使用utcnow()的示例可以在这里找到:https://bitbucket.org/k_bx/blog/src/tip/source/en_posts/2012-07-13-double-call-hack.rst?at=default

monkeypatch的最小工作示例

这个解决方案使用https://pypi.org/project/pytest-mock/包中的monkeypatch。

特点:

仅模拟datetime.today()，但datetime.now()仍然可以正常工作 仅在特定范围内模拟(即块)

import sys
from datetime import datetime

MOCKED_DATETIME_TODAY = datetime(1900, 1, 1, 0, 0, 0)

class MockedDatetime(datetime):
    @classmethod
    def today(cls):
        return MOCKED_DATETIME_TODAY

def test_mock_datetime_today(monkeypatch):
    """Only datetime.today() is mocked and returns some date in 1900. datetime.now() returns still the current date."""
    with monkeypatch.context() as mpc:
        mpc.setattr(sys.modules[__name__], 'datetime', MockedDatetime)
        assert datetime.today() == MOCKED_DATETIME_TODAY  # datetime.today() mocked
        assert datetime.now() > MOCKED_DATETIME_TODAY    # datetime.now() not mocked

    assert datetime.today() > MOCKED_DATETIME_TODAY  # not mocked anymore

对于那些在测试类中使用补丁程序的人，下面是我如何成功地修补datetime功能:

from datetime import datetime
import unittest
from unittest.mock import Mock, patch

# Replace with the proper path to the module you would
# like datetime to be mocked
from path.to.my_module

class MyTestCases(unittest.TestCase):

    def setUp(self):
        """execute on class instantiation"""
        # Record both times at the same moment
        self.dt_now, self.dt_utcnow = datetime.now(), datetime.utcnow()

        # After retrieving real (or hardcoded datetime values), 
        # proceed to mock them in desired module
        self.patch_datetime_functions()


    def patch_datetime_functions(self) -> None:
        """
        Patch datetime.now() and datetime.utcnow() to prevent issues when
        comparing expected dates
        """

        # Create a patcher
        self.patcher_dt = patch(
            'path.to.my_module'
        )

        # Start but make sure cleanup always occurs
        self.patcher_dt.start()
        self.addCleanup(self.patcher_dt.stop)

        # Perform the actual patch – use lambdas as mock functions
        datetime_mock = Mock(wraps=datetime)
        datetime_mock.now.return_value = self.dt_now
        datetime_mock.utcnow.return_value = self.dt_utcnow

        my_module.datetime = datetime_mock


    # Here's what it will look like when testing:
    def some_test(self):
        curr_dt = self.dt_now
        returned_dt = my_module.datetime.utcnow()
        
        # Compare the dates
        self.assertEqual(curr_dt, returned_dt,
            'Datetime values should be equal'
        )