在单元测试中运行带有参数的python文件

Question

我有一个测试用例，我想能够运行带有参数的python文件。

我有2个档案。 app.py

def process_data(arg1,arg2,arg3):
        return {'msg':'ok'}


if __name__ == "__main__":
      arg1 = sys.argv[1]
      arg2 = sys.argv[2]
      arg3 = sys.argv[3]
      process_data(arg1,arg2,arg3)

test_cases.py

class TestCase(unittest.TestCase):

  def test_case1(self):

    expected_output = {'msg':'ok'}
    with os.popen("echo python app.py arg1 arg2 arg3") as o:
        output = o.read()
    output = output.strip()
    self.assertEqual(output, expected_output)





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

预期结果为{'msg'：'ok'}，但是变量输出不返回任何内容。

Answer 1

您不需要使用os.popen（）来调用该函数，您可以直接在test_cases.py中导入该函数并调用它（强烈推荐），请参见以下示例：

from app import process_data

class TestCase(unittest.TestCase):

    def test_case1(self):

        expected_output = {'msg':'ok'}
        output = process_data('arg1', 'arg2', 'arg3')
        self.assertEqual(output, expected_output)


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

Answer 2

您忘记的一件事是进程输出将作为字符串返回，但是您正在与dict进行比较，所以Expect_output expected_output = "{'msg': 'ok'}"变化很小

import os
import unittest


class TestCase(unittest.TestCase):

    def test_case1(self):
        expected_output = "{'msg': 'ok'}"
        output = os.popen('python3 app.py arg1 arg2 arg3').read().strip()
        print('=============>', output)
        self.assertEqual(output, expected_output)


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

app.py

import sys


def process_data(arg1, arg2, arg3):
    print({'msg': 'ok'})
    # return pass


if __name__ == "__main__":
    arg1 = sys.argv[1]
    arg2 = sys.argv[2]
    arg3 = sys.argv[3]
    process_data(arg1, arg2, arg3)

输出：

Ran 1 test in 0.025s

OK
=============> {'msg': 'ok'}