test_os.py 文件源码

def _execvpe_mockup(defpath=None):
    """
    Stubs out execv and execve functions when used as context manager.
    Records exec calls. The mock execv and execve functions always raise an
    exception as they would normally never return.
    """
    # A list of tuples containing (function name, first arg, args)
    # of calls to execv or execve that have been made.
    calls = []

    def mock_execv(name, *args):
        calls.append(('execv', name, args))
        raise RuntimeError("execv called")

    def mock_execve(name, *args):
        calls.append(('execve', name, args))
        raise OSError(errno.ENOTDIR, "execve called")

    try:
        orig_execv = os.execv
        orig_execve = os.execve
        orig_defpath = os.defpath
        os.execv = mock_execv
        os.execve = mock_execve
        if defpath is not None:
            os.defpath = defpath
        yield calls
    finally:
        os.execv = orig_execv
        os.execve = orig_execve
        os.defpath = orig_defpath