将nosetests 与Python 合约相结合

Question

我使用 Python 合约 来指定前置条件/​​后置条件/不变量。 我还使用 doctests 进行单元测试。

我希望在启用合同的情况下运行所有​​ doctest 单元测试，并且我希望使用 鼻子。 不幸的是，如果我用鼻子运行测试，它不会执行前/后/不变断言。 我放置了 设置函数< /a> 在每个 .py 文件中以确保调用 contract.checkmod

def setup():
    import contract
    contract.checkmod(__name__)

我可以确认该函数在运行测试之前正在由鼻子执行，但合约仍然没有被执行。

另一方面，如果我通过调用 doctest.testmod 运行 doctest，则 pre/post/inv 确实会被调用：

def _test():
    import contract
    contract.checkmod(__name__)
    import doctest
    doctest.testmod()

if __name__=='__main__':    
    _test()

这是一个 Python 脚本的示例，如果直接调用，该脚本的测试将成功，但会失败如果用鼻子调用：

import os

def setup():
    import contract
    contract.checkmod(__name__)

def delete_file(path):
    """Delete a file. File must be present.

    >>> import minimock
    >>> minimock.mock('os.remove')
    >>> minimock.mock('os.path.exists', returns=True)

    >>> delete_file('/tmp/myfile.txt')
    Called os.path.exists('/tmp/myfile.txt')
    Called os.remove('/tmp/myfile.txt')

    >>> minimock.restore()

    pre: os.path.exists(path)
    """
    os.remove(path)

if __name__ == '__main__':
    setup()
    import doctest
    doctest.testmod()

当我独立运行上述文件时，测试通过：

$ python contracttest.py -v
Trying:
    import minimock
Expecting nothing
ok
Trying:
    minimock.mock('os.remove')
Expecting nothing
ok
Trying:
    minimock.mock('os.path.exists', returns=True)
Expecting nothing
ok
Trying:
    delete_file('/tmp/myfile.txt')
Expecting:
    Called os.path.exists('/tmp/myfile.txt')
    Called os.remove('/tmp/myfile.txt')
ok
Trying:
    minimock.restore()
Expecting nothing
ok
2 items had no tests:
    __main__
    __main__.setup
1 items passed all tests:
   5 tests in __main__.delete_file
5 tests in 3 items.
5 passed and 0 failed.
Test passed.

这是用鼻子：

$ nosetests --with-doctest contracttest.py
F
======================================================================
FAIL: Doctest: contracttest.delete_file
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/doctest.py", line 2131, in runTest
    raise self.failureException(self.format_failure(new.getvalue()))
AssertionError: Failed doctest test for contracttest.delete_file
  File "/Users/lorin/Desktop/contracttest.py", line 10, in delete_file

----------------------------------------------------------------------
File "/Users/lorin/Desktop/contracttest.py", line 17, in contracttest.delete_file
Failed example:
    delete_file('/tmp/myfile.txt')
Expected:
    Called os.path.exists('/tmp/myfile.txt')
    Called os.remove('/tmp/myfile.txt')
Got:
    Called os.remove('/tmp/myfile.txt')


----------------------------------------------------------------------
Ran 1 test in 0.055s