python - 使用 unittest discover 传递参数(对于 argparse)

Question

foo 是一个目录嵌套很深的 Python 项目，在各个子目录下包含了约 30 个 unittest 文件。在 foo 的 setup.py 中，我有 added a custom "test" command内部运行

 python -m unittest discover foo '*test.py'

请注意，这使用了 unittest's discovery模式。

---

由于一些测试非常慢，我最近决定测试应该有“级别”。 this question的答案很好地解释了如何让 unittest 和 argparse 很好地协同工作。所以现在，我可以运行一个个人单元测试文件，例如foo/bar/_bar_test.py，

python foo/bar/_bar_test.py --level=3

并且只运行 3 级测试。

问题是我无法弄清楚如何传递自定义标志(在本例中为“--level=3”，使用 discover。我尝试的一切都失败了，例如:

$ python -m unittest discover --level=3 foo '*test.py'
Usage: python -m unittest discover [options]

python -m unittest discover: error: no such option: --level

$ python -m --level=3 unittest discover foo '*test.py'
/usr/bin/python: No module named --level=3

如何将 --level=3 传递给各个单元测试？如果可能，我想避免将不同级别的测试划分到不同的文件中。

赏金编辑

赏金前(罚款)解决方案建议使用系统环境变量。这还不错，但我正在寻找更清洁的东西。

将多文件测试运行程序(即 python -m unittest discover foo '*test.py')更改为其他内容没问题，只要:

1. 它允许为多文件单元测试生成单个报告。
2. 它可以以某种方式支持多个测试级别(使用问题中的技术，或使用其他一些不同的机制)。

Answer 1

这不会使用 unittest discover 传递 args，但它会完成您正在尝试做的事情。

这是leveltest.py。将它放在模块搜索路径中的某处(可能是当前目录或站点包):

import argparse
import sys
import unittest

# this part copied from unittest.__main__.py
if sys.argv[0].endswith("__main__.py"):
    import os.path
    # We change sys.argv[0] to make help message more useful
    # use executable without path, unquoted
    # (it's just a hint anyway)
    # (if you have spaces in your executable you get what you deserve!)
    executable = os.path.basename(sys.executable)
    sys.argv[0] = executable + " -m leveltest"
    del os

def _id(obj):
    return obj

# decorator that assigns test levels to test cases (classes and methods)
def level(testlevel):
    if unittest.level < testlevel:
        return unittest.skip("test level too low.")
    return _id

def parse_args():
    parser = argparse.ArgumentParser()
    parser.add_argument('--level', type=int, default=3)
    ns, args = parser.parse_known_args(namespace=unittest)
    return ns, sys.argv[:1] + args

if __name__ == "__main__":
    ns, remaining_args = parse_args()

    # this invokes unittest when leveltest invoked with -m flag like:
    #    python -m leveltest --level=2 discover --verbose
    unittest.main(module=None, argv=remaining_args)

以下是如何在示例 testproject.py 文件中使用它:

import unittest
import leveltest

# This is needed before any uses of the @leveltest.level() decorator
#   to parse the "--level" command argument and set the test level when 
#   this test file is run directly with -m
if __name__ == "__main__":
    ns, remaining_args = leveltest.parse_args()

@leveltest.level(2)
class TestStringMethods(unittest.TestCase):

    @leveltest.level(5)
    def test_upper(self):
        self.assertEqual('foo'.upper(), 'FOO')

    @leveltest.level(3)
    def test_isupper(self):
        self.assertTrue('FOO'.isupper())
        self.assertFalse('Foo'.isupper())

    @leveltest.level(4)
    def test_split(self):
        s = 'hello world'
        self.assertEqual(s.split(), ['hello', 'world'])
        # check that s.split fails when the separator is not a string
        with self.assertRaises(TypeError):
            s.split(2)

if __name__ == '__main__':
    # this invokes unittest when this file is executed with -m
    unittest.main(argv=remaining_args)

然后您可以通过直接运行 testproject.py 来运行测试，例如:

~roottwo\projects> python testproject.py --level 2 -v
test_isupper (__main__.TestStringMethods) ... skipped 'test level too low.'
test_split (__main__.TestStringMethods) ... skipped 'test level too low.'
test_upper (__main__.TestStringMethods) ... skipped 'test level too low.'

----------------------------------------------------------------------
Ran 3 tests in 0.000s

OK (skipped=3)

~roottwo\projects> python testproject.py --level 3 -v
test_isupper (__main__.TestStringMethods) ... ok
test_split (__main__.TestStringMethods) ... skipped 'test level too low.'
test_upper (__main__.TestStringMethods) ... skipped 'test level too low.'

----------------------------------------------------------------------
Ran 3 tests in 0.001s

OK (skipped=2)

~roottwo\projects> python testproject.py --level 4 -v
test_isupper (__main__.TestStringMethods) ... ok
test_split (__main__.TestStringMethods) ... ok
test_upper (__main__.TestStringMethods) ... skipped 'test level too low.'

----------------------------------------------------------------------
Ran 3 tests in 0.001s

OK (skipped=1)

~roottwo\projects> python testproject.py --level 5 -v
test_isupper (__main__.TestStringMethods) ... ok
test_split (__main__.TestStringMethods) ... ok
test_upper (__main__.TestStringMethods) ... ok

----------------------------------------------------------------------
Ran 3 tests in 0.001s

OK

通过像这样使用单元测试发现:

~roottwo\projects> python -m leveltest --level 2 -v
test_isupper (testproject.TestStringMethods) ... skipped 'test level too low.'
test_split (testproject.TestStringMethods) ... skipped 'test level too low.'
test_upper (testproject.TestStringMethods) ... skipped 'test level too low.'

----------------------------------------------------------------------
Ran 3 tests in 0.003s

OK (skipped=3)

~roottwo\projects> python -m leveltest --level 3 discover -v
test_isupper (testproject.TestStringMethods) ... ok
test_split (testproject.TestStringMethods) ... skipped 'test level too low.'
test_upper (testproject.TestStringMethods) ... skipped 'test level too low.'

----------------------------------------------------------------------
Ran 3 tests in 0.001s

OK (skipped=2)

~roottwo\projects> python -m leveltest --level 4 -v
test_isupper (testproject.TestStringMethods) ... ok
test_split (testproject.TestStringMethods) ... ok
test_upper (testproject.TestStringMethods) ... skipped 'test level too low.'

----------------------------------------------------------------------
Ran 3 tests in 0.001s

OK (skipped=1)

~roottwo\projects> python -m leveltest discover --level 5 -v
test_isupper (testproject.TestStringMethods) ... ok
test_split (testproject.TestStringMethods) ... ok
test_upper (testproject.TestStringMethods) ... ok

----------------------------------------------------------------------
Ran 3 tests in 0.001s

OK

或者通过指定要运行的测试用例，例如:

~roottwo\projects>python -m leveltest --level 3 testproject -v
test_isupper (testproject.TestStringMethods) ... ok
test_split (testproject.TestStringMethods) ... skipped 'test level too low.'
test_upper (testproject.TestStringMethods) ... skipped 'test level too low.'

----------------------------------------------------------------------
Ran 3 tests in 0.002s

OK (skipped=2)