在python中重载unittest.testcase

Question

我试图通过对unittest.testcase类进行子类化来创建自定义单元测试框架,但在处理该__init__方法时似乎犯了一个错误.

我无法弄清楚为什么构造函数在ComplexTest进入之前没有被调用BasicTest,异常似乎也与我的构造函数有关.

我是Python的新手,所以对于如何解决这个特定问题或我的用例的替代架构的任何帮助都将是非常受欢迎的.

谢谢!

1)test_framework.py

import unittest

class BasicTest(unittest.TestCase):
    def __init__(self, *args, **kwargs):
        print('BasicTest.__init__')
        super(unittest.TestCase, self).__init__(*args, **kwargs)

    def setUp(self):
        print('BasicTest.setUp')
        super(unittest.TestCase, self).tearDown()

    def tearDown(self):
        print('BasicTest.tearDown')
        super(unittest.TestCase, self).tearDown()


class ComplexTest(BasicTest):
    def __init__(self, *args, **kwargs):
        print('ComplexTest.__init__')
        super(BasicTest, self).__init__(*args, **kwargs)

    def setUp(self):
        print('ComplexTest.setUp')
        super(BasicTest, self).tearDown()

    def tearDown(self):
        print('ComplexTest.tearDown')
        super(BasicTest, self).tearDown()

2)test.py

import unittest
import test_framework

class TestValueFunctions(test_framework.ComplexTest):
    def __init__(self, *args, **kwargs):
        print('TestValueFunctions.__init__')
        super(test_framework.ComplexTest, self).__init__(*args, **kwargs)

    def setUp(self):
        print('TestValueFunctions.setUp')
        super(test_framework.ComplexTest, self).tearDown()
        self.value = 4711

    def tearDown(self):
        print('TestValueFunctions.tearDown')
        super(test_framework.ComplexTest, self).tearDown()

    def test_value(self):
        print('TestValueFunctions.test_value')
        self.assertEqual(self.value, 4711)

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

3)当现在尝试运行它时,我看到下面的堆栈

TestValueFunctions.__init__
BasicTest.__init__
Traceback (most recent call last):
  File "D:\MyDev\ljs_app\trunk\examples\python\unittest\test.py", line 23, in <module>
    unittest.main()
  File "C:\Python27\lib\unittest\main.py", line 94, in __init__
    self.parseArgs(argv)
  File "C:\Python27\lib\unittest\main.py", line 149, in parseArgs
    self.createTests()
  File "C:\Python27\lib\unittest\main.py", line 155, in createTests
    self.test = self.testLoader.loadTestsFromModule(self.module)
  File "C:\Python27\lib\unittest\loader.py", line 65, in loadTestsFromModule
    tests.append(self.loadTestsFromTestCase(obj))
  File "C:\Python27\lib\unittest\loader.py", line 56, in loadTestsFromTestCase
    loaded_suite = self.suiteClass(map(testCaseClass, testCaseNames))
  File "D:\MyDev\ljs_app\trunk\examples\python\unittest\test.py", line 7, in __init__
    super(test_framework.ComplexTest, self).__init__(*args, **kwargs)
  File "D:\MyDev\ljs_app\trunk\examples\python\unittest\test_framework.py", line 6, in __init__
    super(unittest.TestCase, self).__init__(*args, **kwargs)
TypeError: object.__init__() takes no parameters

Answer 1

确实你的init方法是错误的.

class BasicTest(unittest.TestCase):
    def __init__(self, *args, **kwargs):
        print('BasicTest.__init__')
        super(unittest.TestCase, self).__init__(*args, **kwargs)

应该:

class BasicTest(unittest.TestCase):
    def __init__(self, *args, **kwargs):
        print('BasicTest.__init__')
        super(BasicTest, self).__init__(*args, **kwargs)

这将调用__init__BasicTest的母类,即TestCase.setUp和tearDown的情况相同:

class BasicTest(unittest.TestCase):
    ...
    def setUp(self):
        print('BasicTest.setUp')
        super(BasicTest, self).setUp()