无法在 ipython/jupyter notebook 中运行 unittest 的主要功能

Question

我举了一个在 ipython/jupyter notebook 中抛出错误的例子，但作为一个单独的脚本运行良好。

import unittest

class Samples(unittest.TestCase):

    def testToPow(self):
        pow3 = 3**3
        assert pow3==27

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

错误如下：

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-7-232db94ae8b2> in <module>()
      8 
      9 if __name__ == '__main__':
---> 10     unittest.main()

/usr/local/Cellar/python/2.7.10_2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/main.pyc in __init__(self, module, defaultTest, argv, testRunner, testLoader, exit, verbosity, failfast, catchbreak, buffer)
     92         self.testLoader = testLoader
     93         self.progName = os.path.basename(argv[0])
---> 94         self.parseArgs(argv)
     95         self.runTests()
     96 

/usr/local/Cellar/python/2.7.10_2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/main.pyc in parseArgs(self, argv)
    147             else:
    148                 self.testNames = (self.defaultTest,)
--> 149             self.createTests()
    150         except getopt.error, msg:
    151             self.usageExit(msg)

/usr/local/Cellar/python/2.7.10_2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/main.pyc in createTests(self)
    156         else:
    157             self.test = self.testLoader.loadTestsFromNames(self.testNames,
--> 158                                                            self.module)
    159 
    160     def _do_discovery(self, argv, Loader=None):

/usr/local/Cellar/python/2.7.10_2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/loader.pyc in loadTestsFromNames(self, names, module)
    128         of string specifiers. See 'loadTestsFromName()'.
    129         """
--> 130         suites = [self.loadTestsFromName(name, module) for name in names]
    131         return self.suiteClass(suites)
    132 

/usr/local/Cellar/python/2.7.10_2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/loader.pyc in loadTestsFromName(self, name, module)
     98         obj = module
     99         for part in parts:
--> 100             parent, obj = obj, getattr(obj, part)
    101 
    102         if isinstance(obj, types.ModuleType):

AttributeError: 'module' object has no attribute '/Users/root3d/Library/Jupyter/runtime/kernel-c5225ac4-4b0e-4473-ae0a-3e051a704561'

可能的问题是什么？ 那么我应该如何在笔记本中编写测试呢？

Answer 1

unittest.main默认查看sys.argv ，这是启动 IPython 的原因，因此有关内核连接文件不是有效属性的错误。 您可以将显式列表传递给main以避免查找 sys.argv。

在笔记本中，您还需要包含exit=False以防止 unittest.main 尝试关闭内核进程：

unittest.main(argv=['first-arg-is-ignored'], exit=False)

您可以在 argv 列表中传递更多参数，例如

unittest.main(argv=['ignored', '-v'], exit=False)

Answer 2

我们可以尝试TestLoader从TestCaseClass加载测试用例

并将这些测试用例附加到TextTestRunner然后运行它。

import unittest
suite = unittest.TestLoader().loadTestsFromTestCase(Samples)
runner = unittest.TextTestRunner(verbosity=2)
runner.run(suite)

Answer 3

@Hari Baskar 的答案可以通过定义一个装饰器来通用：

def run_test(tcls):
    """
    Runs unit tests from a test class
    :param tcls: A class, derived from unittest.TestCase
    """
    suite = unittest.TestLoader().loadTestsFromTestCase(tcls)
    runner = unittest.TextTestRunner(verbosity=2)
    runner.run(suite)

通过将@run_test装饰器应用于要测试的类来运行测试：

@run_test
class Samples(unittest.TestCase):
    def testToPow(self):
        pow3 = 3**3
        # use the tools the unittest module gives you...
        self.assertEqual(pow3, 27)