如何将文件传递给 unittest.mock.mock_open()？

Question

我有一个读取日志文件和过滤结果的函数，我想测试以确保它正确过滤。我的代码import osimport randomimport unittestfrom unittest.mock import patch, mock_open__SAMPLE_LOG__ = os.path.join(settings.BASE_DIR, "apps/tests/log_viewer/sample_logs/sample_manager_log.log")class FilterLog(unittest.TestCase):    def setUp(self):        with open(__SAMPLE_LOG__) as f:            self.sample_data = f.read()    @patch('builtins.open', new_callable = mock_open, read_data = self.sample_data)    def test_filterDate(self, mock_file):                day = '08'        month = '08'        year = '2019'        results = filter_log(filter_by = 'date', day = day, month = month, year = year)        self.assertEqual(open(settings.ACTIVITY_LOG_FILE).read(), self.sample_data)错误@patch('builtins.open', new_callable = mock_open, read_data = self.sample_data)NameError：名称“自我”未定义我的问题我应该如何将数据传递到mock_open()？我觉得with open() ... read()在文件顶部有一个不好的做法，我也不能把它作为一个类变量（可以吗？），那么我有什么选择呢？文件说什么从文档 read_data中获取一个字符串，所以我需要以某种方式将文件读入一个变量并将其传入。但是在哪里读取文件合适？在模块的顶部，在课程的开头，还是在setUp()？

Answer 1

这应该有效。我把 sample_data 带出了课堂。

import os

import random

import unittest

from unittest.mock import patch, mock_open

__SAMPLE_LOG__ = os.path.join(settings.BASE_DIR, "apps/tests/log_viewer/sample_logs/sample_manager_log.log")

# read your test data in sample_data

with open(__SAMPLE_LOG__) as f:

    sample_data = f.read()

class FilterLog(unittest.TestCase):

    @patch('builtins.open', new_callable = mock_open, read_data = sample_data)

    def test_filterDate(self, mock_file):

        day = '08'

        month = '08'

        year = '2019'

        results = filter_log(filter_by = 'date', day = day, month = month, year = year)

        self.assertEqual(open(settings.ACTIVITY_LOG_FILE).read(), sample_data)