我有一些测试数据,想为每个项目创建一个单元测试。我的第一个想法是这样做的:

import unittest

l = [["foo", "a", "a",], ["bar", "a", "b"], ["lee", "b", "b"]]

class TestSequence(unittest.TestCase):
    def testsample(self):
        for name, a,b in l:
            print "test", name
            self.assertEqual(a,b)

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

这样做的缺点是它在一个测试中处理所有数据。我想在飞行中为每个项目生成一个测试。有什么建议吗?


当前回答

我在一种非常特殊的参数化测试风格上遇到了麻烦。我们所有的Selenium测试都可以在本地运行,但它们也应该能够在SauceLabs上的多个平台上远程运行。基本上,我想要使用大量已经编写好的测试用例,并用尽可能少的代码更改参数化它们。此外,我需要能够将参数传递到setUp方法中,这是我在其他地方没有看到的任何解决方案。

以下是我想到的:

import inspect
import types

test_platforms = [
    {'browserName': "internet explorer", 'platform': "Windows 7", 'version': "10.0"},
    {'browserName': "internet explorer", 'platform': "Windows 7", 'version': "11.0"},
    {'browserName': "firefox", 'platform': "Linux", 'version': "43.0"},
]


def sauce_labs():
    def wrapper(cls):
        return test_on_platforms(cls)
    return wrapper


def test_on_platforms(base_class):
    for name, function in inspect.getmembers(base_class, inspect.isfunction):
        if name.startswith('test_'):
            for platform in test_platforms:
                new_name = '_'.join(list([name, ''.join(platform['browserName'].title().split()), platform['version']]))
                new_function = types.FunctionType(function.__code__, function.__globals__, new_name,
                                                  function.__defaults__, function.__closure__)
                setattr(new_function, 'platform', platform)
                setattr(base_class, new_name, new_function)
            delattr(base_class, name)

    return base_class

With this, all I had to do was add a simple decorator @sauce_labs() to each regular old TestCase, and now when running them, they're wrapped up and rewritten, so that all the test methods are parameterized and renamed. LoginTests.test_login(self) runs as LoginTests.test_login_internet_explorer_10.0(self), LoginTests.test_login_internet_explorer_11.0(self), and LoginTests.test_login_firefox_43.0(self), and each one has the parameter self.platform to decide what browser/platform to run against, even in LoginTests.setUp, which is crucial for my task since that's where the connection to SauceLabs is initialized.

无论如何,我希望这对那些希望对他们的测试进行类似的“全局”参数化的人有所帮助!

其他回答

这可以使用元类优雅地解决:

import unittest

l = [["foo", "a", "a",], ["bar", "a", "b"], ["lee", "b", "b"]]

class TestSequenceMeta(type):
    def __new__(mcs, name, bases, dict):

        def gen_test(a, b):
            def test(self):
                self.assertEqual(a, b)
            return test

        for tname, a, b in l:
            test_name = "test_%s" % tname
            dict[test_name] = gen_test(a,b)
        return type.__new__(mcs, name, bases, dict)

class TestSequence(unittest.TestCase):
    __metaclass__ = TestSequenceMeta

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

基于元类的答案在Python 3中仍然有效,但必须使用元类参数,而不是__metaclass__属性,例如:

class ExampleTestCase(TestCase,metaclass=DocTestMeta):
    pass

我发现这很适合我的目的,特别是当我需要生成在数据集合上执行稍微不同的过程的测试时。

import unittest

def rename(newName):
    def renamingFunc(func):
        func.__name__ == newName
        return func
    return renamingFunc

class TestGenerator(unittest.TestCase):

    TEST_DATA = {}

    @classmethod
    def generateTests(cls):
        for dataName, dataValue in TestGenerator.TEST_DATA:
            for func in cls.getTests(dataName, dataValue):
                setattr(cls, "test_{:s}_{:s}".format(func.__name__, dataName), func)

    @classmethod
    def getTests(cls):
        raise(NotImplementedError("This must be implemented"))

class TestCluster(TestGenerator):

    TEST_CASES = []

    @staticmethod
    def getTests(dataName, dataValue):

        def makeTest(case):

            @rename("{:s}".format(case["name"]))
            def test(self):
                # Do things with self, case, data
                pass

            return test

        return [makeTest(c) for c in TestCluster.TEST_CASES]

TestCluster.generateTests()

TestGenerator类可以用来生成不同的测试用例集,比如TestCluster。

TestCluster可以被认为是TestGenerator接口的实现。

您将从尝试testscenario库中受益。

testscenes为python unittest风格的测试提供了干净的依赖注入。这可以用于接口测试(通过单个测试套件测试许多实现)或经典的依赖项注入(在测试代码本身的外部提供依赖项测试,允许在不同情况下轻松测试)。

这实际上与之前的回答中提到的parameterized相同,但具体到unittest:

def sub_test(param_list):
    """Decorates a test case to run it as a set of subtests."""

    def decorator(f):

        @functools.wraps(f)
        def wrapped(self):
            for param in param_list:
                with self.subTest(**param):
                    f(self, **param)

        return wrapped

    return decorator

使用示例:

class TestStuff(unittest.TestCase):
    @sub_test([
        dict(arg1='a', arg2='b'),
        dict(arg1='x', arg2='y'),
    ])
    def test_stuff(self, arg1, arg2):
        ...