使用unittest discover传递参数(对于argparse)

Question

foo是一个具有深层目录嵌套的Python项目,包括unittest各种子目录中的~30个文件.在foos内setup.py,我在内部运行了一个自定义的"test"命令

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

请注意,这使用了unittest发现模式.

---

由于一些测试非常慢,我最近决定测试应该有"级别".这个问题的答案非常清楚地说明了如何相处unittest并argparse相互配合.所以,现在,我可以运行一个单独的单元测试文件,比方说foo/bar/_bar_test.py,与

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使用发现传递自定义标志(在本例中为"--level = 3".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

我怎样才能--level=3转到单独的单元测试？如果可能的话,我想避免将不同级别的测试划分为不同的文件.

赏金编辑

pre-bounty(精细)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.

将多文件测试运行器(即python -m unittest discover foo'*test.py')更改为其他内容很好,只要:

1. 它允许为多文件单元测试生成单个报告.
2. 它可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，但它会完成您想要做的事情。

这是leveltest.py。将它放在模块搜索路径中的某个位置（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)

以下是在示例 testproject.py 文件中使用它的方法：

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)

Answer 2

使用discover时无法传递参数. DiscoveringTestLoaderclass from discover,删除所有不匹配的文件(删除使用'*test.py --level = 3')并仅将文件名传递到unittest.TextTestRunner

到目前为止,可能只有使用环境变量的选项

LEVEL=3 python -m unittest discoverfoo '*test.py'

Answer 3

您遇到的问题是 unittest 参数解析器根本不理解此语法。因此，您必须在调用 unittest 之前删除参数。

一个简单的方法是创建一个包装模块（比如 my_unittest.py）来查找额外的参数，从 sys.argv 中去除它们，然后调用 unittest 中的主条目。

现在为好一点...该包装器的代码与您已经用于单个文件案例的代码基本相同！你只需要把它放到一个单独的文件中。

编辑：根据要求在下面添加了示例代码...

首先，运行 UT 的新文件 (my_unittest.py)：

import sys
import unittest
from parser import wrapper

if __name__ == '__main__':
    wrapper.parse_args()
    unittest.main(module=None, argv=sys.argv)

现在 parser.py，它必须在一个单独的文件中，以避免在__main__模块中使全局引用起作用：

import sys
import argparse
import unittest

class UnitTestParser(object):

    def __init__(self):
        self.args = None

    def parse_args(self):
        # Parse optional extra arguments
        parser = argparse.ArgumentParser()
        parser.add_argument('--level', type=int, default=0)
        ns, args = parser.parse_known_args()
        self.args = vars(ns)

        # Now set the sys.argv to the unittest_args (leaving sys.argv[0] alone)
        sys.argv[1:] = args

wrapper = UnitTestParser()

最后是一个示例测试用例 (project_test.py) 来测试参数是否正确解析：

import unittest
from parser import wrapper

class TestMyProject(unittest.TestCase):

    def test_len(self):
        self.assertEqual(len(wrapper.args), 1)

    def test_level3(self):
        self.assertEqual(wrapper.args['level'], 3)

现在证明：

$ python -m my_unittest discover --level 3 . '*test.py'
..
----------------------------------------------------------------------
Ran 2 tests in 0.000s

OK