python - 是否可以从 python unittest.TestCase 运行单个测试方法并引用该方法？

Question

假设我有以下TestCase

class TestSomething(unittest.TestCase):
    def test_a(self):
        # Do some testing

    def test_b(self):
        # Do some other testing

如果我有对该测试的引用，我是否可以运行TestSomething.test_a？我想做的是:

def run_test(test):
    # Somehow runs the test
    # HERE IS THE PART I AM REALLY STUCK ON

run_test(TestSomething.test_a)

我知道这对于正常的单元测试来说是一件尴尬的事情。我想做的是提供一个测试作为函数装饰器的参数运行。本质上:

@corresponding_test(TestSomething.test_a)
def my_function_a():
    # Something here

然后在装饰器中，在运行函数之前检查该函数的测试是否通过。

Answer 1

OP 明确指出现实世界的用例涉及更多，但这仍然需要说:

免责声明:这不是运行单元测试的良好标准方法。如果您使用此代码来运行单元测试，那么您[可能]做错了。

也就是说，你的问题引起了我的兴趣，所以我继续为你编写了一个工作演示:

"""
The `only_if_test_passes` decorator can be used to run a function if and
only if the argument test (unbound `TestCase` method) passes.
"""

import inspect
from unittest import TestCase, TestResult


class TestError(Exception):
    pass


class MyTests(TestCase):

    def test_pass(self):
        # This passes because nothing went wrong
        pass

    def test_fail(self):
        self.fail('This test will always fail')


def only_if_test_passes(test_method):
    # Comments are computed values when passed MyTests.test_pass
    test_case_class = inspect._findclass(test_method)  # MyTests
    test_case_name = test_case_class.__name__  # 'MyTests'
    test_name = test_method.__name__  # 'test_pass'
    # Introspection for Python 2:
    # test_case_class = test_method.im_class
    # test_case_name = test_case_class.__name__  # Same as for Python 3
    # test_name = test_method.if_func.func_name

    def decorator(fn):
        def decorated(*args, **kwargs):
            test_result = TestResult()
            case = test_case_class(test_name)  # MyTests('test_pass')
            case(test_result)
            if test_result.wasSuccessful():
                return fn(*args, **kwargs)
            else:
                raise TestError('Unit test failed: {}.{}'.format(
                    test_case_name, test_name))
        return decorated
    return decorator


@only_if_test_passes(MyTests.test_pass)
def this_will_run():
    print('This should output')


@only_if_test_passes(MyTests.test_fail)
def this_wont_ever_run():
    print("Don't bother; you'll never see this.")


if __name__ == "__main__":
    this_will_run()
    this_wont_ever_run()

gist

Python 2 中的内省(introspection)会略有不同。

另请参阅:unittest.TestCase docs