在 Python 中模拟子进程调用

我有一个方法——run_script()- 我想测试一下。具体来说，我想测试一下调用subprocess.Popen https://docs.python.org/3/library/subprocess.html#subprocess.Popen发生。测试一下会更好subprocess.Popen使用某些参数进行调用。当我运行测试时，我得到了TypeError: 'tuple' object is not callable.

我如何测试我的方法以确保subprocess实际上是使用模拟来调用的吗？

@mock.patch("subprocess.Popen")
def run_script(file_path):
    process = subprocess.Popen(["myscript", -M, file_path], stdout=subprocess.PIPE)
    output, err = process.communicate()
    return process.returncode


def test_run_script(self, mock_subproc_popen):
    mock_subproc_popen.return_value = mock.Mock(
        communicate=("ouput", "error"), returncode=0
    )
    am.account_manager("path")
    self.assertTrue(mock_subproc_popen.called)

对我来说，你使用补丁装饰器而不是run_script函数，因为你没有在那里传递模拟参数。

这个怎么样：

from unittest import mock
import subprocess

def run_script(file_path):
    process = subprocess.Popen(["myscript", -M, file_path], stdout=subprocess.PIPE)
    output, err = process.communicate()
    return process.returncode


@mock.patch("subprocess.Popen")
def test_run_script(self, mock_subproc_popen):
    process_mock = mock.Mock()
    attrs = {"communicate.return_value": ("output", "error")}
    process_mock.configure_mock(**attrs)
    mock_subproc_popen.return_value = process_mock
    am.account_manager("path")  # this calls run_script somewhere, is that right?
    self.assertTrue(mock_subproc_popen.called)

现在，您的模拟 subprocess.Popen 似乎返回一个元组，导致 process.communicate() 引发TypeError: 'tuple' object is not callable.。因此，最重要的是让mock_subproc_popen 的return_value 恰到好处。