Python 3.x 代码覆盖率，函数的Unittest在Python中引发异常 class Kill\u任务： 定义初始化（自）： self.action=无 self.cmd=[] def kill_任务（自我）： self.action=False #exp task=chrome.exe 目标='chrome.exe' 尝试： self.cmd=supprocess.run（['taskkill'，'/im'，target'，/f']，capture\u output=True，check=True） self.action=True 除subprocess.CalledProcessError为e外： 打印（e） self.action=False return self.cmd 需要def操作（自身）： 尝试=3 对于范围内的i（尝试）： 尝试： self.kill_任务（） self.action=True 除subprocess.CalledProcessError为e外： self.action=False 如果我

除最后一个功能“测试\操作\必需\异常”外，上述所有功能均正常工作。函数应该返回False而不是True。

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我正在为test\u action\u required\u异常函数进行代码覆盖。但我无法检查异常，因为它总是正确的。我需要模拟还是不需要能够测试异常？请帮帮我！谢谢

@slideshowp2嗨，如果可以的话，你能帮我完成最后一个功能吗

class Kill_Tasks:
   def __init__(self):
      self.action = None
      self.cmd=[]
   def kill_tasks(self):
      self.action = False
      #exp task = chrome.exe
      target = 'chrome.exe'
      try:
         self.cmd = suprocess.run(['taskkill','/im', target,'/f'],capture_output=True, check=True)
         self.action = True
      except subprocess.CalledProcessError as e:
         print(e)
         self.action = False
      return self.cmd
   def action_required(self):
         tries = 3
         for i in range(tries):
             try:
                 self.kill_tasks()
                 self.action = True
             except subprocess.CalledProcessError as e:
                 self.action = False
                 if i < tries -1:
                  continue
                 else:
                  raise
            break

import unittest
from unittest.mock import patch
from subprocess import CompletedProcess, CalledProcessError
from kill_tasks import Kill_Tasks


class TestKillTasks(unittest.TestCase):
    @patch('kill_tasks.subprocess.run')
    def test_kill_tasks_success(self, mock_run):
        mock_run.return_value = CompletedProcess(args=['taskkill', '/im', 'chrome.exe', '/f'], returncode=0)
        kill_tasks_instance = Kill_Tasks()
        cmd = kill_tasks_instance.kill_tasks()
        mock_run.assert_called_once_with(['taskkill', '/im', 'chrome.exe', '/f'], capture_output=True, check=True)
        self.assertIsInstance(cmd, CompletedProcess)
        self.assertTrue(kill_tasks_instance.action)

    @patch('kill_tasks.subprocess.run')
    def test_kill_tasks_exception(self, mock_run):
        mock_run.side_effect = CalledProcessError(returncode=1, cmd='123')
        kill_tasks_instance = Kill_Tasks()
        kill_tasks_instance.kill_tasks()
        self.assertFalse(kill_tasks_instance.action)

    @patch('action_required.subprocess.run')
    def test_action_required_success(self, mock_run):
        mock_run.return_value = CompletedProcess(args=['taskkill', '/im', 'chrome.exe', '/f'], returncode=0)
        kill_tasks_instance = Kill_Tasks()
        cmd = kill_tasks_instance.action_required()
        mock_run.assert_called_once_with(['taskkill', '/im', 'chrome.exe', '/f'], capture_output=True, check=True)
        self.assertIsInstance(cmd, CompletedProcess)
        self.assertTrue(kill_tasks_instance.action)

```Need help for the function below:```
    @patch('action_required.subprocess.run')
    def test_action_required_exception(self, mock_run):
        mock_run.side_effect = CalledProcessError(returncode=1, cmd='false')
        kill_tasks_instance = Kill_Tasks()
        kill_tasks_instance.action_required()
        #it returns True, it should return False
        self.assertFalse(kill_tasks_instance.action)


if __name__ == '__main__':
    unittest.main()