Python 模拟不起作用

Question

我需要写一个测试，有 StringIO 和 curl，所以我试着模拟它们，但它返回了错误的数据，与我等待的不一样。

Python 测试函数:

def test_make_curl_request(self):
        redirect_url = 'abc'
        content = 'Content'
        mock_curl = mock.MagicMock()
        mock_curl.getinfo = mock.Mock(return_value=redirect_url)
        mock_curl.setopt = mock.Mock()
        mock_curl.perform = mock.Mock()

        mock_io_string = mock.MagicMock()
        mock_io_string.getvalue = mock.Mock(return_value=content)

        with mock.patch('pycurl.Curl', mock.Mock(return_value=mock_curl)):
            with mock.patch('source.lib.StringIO', mock.Mock(return_value=mock_io_string)):
                with mock.patch('source.lib.to_str', mock.Mock(return_value=redirect_url)):
                    with mock.patch('source.lib.to_unicode', mock.Mock(return_value=redirect_url)):
                        with mock.patch('source.lib.prepare_url', mock.Mock()):
                            self.assertEqual(init.make_pycurl_request('http://test.rg', 10), (content, redirect_url))

测试函数:

def make_pycurl_request(url, timeout, useragent=None):
    prepared_url = to_str(prepare_url(url), 'ignore')
    buff = StringIO()
    curl = pycurl.Curl()
    curl.setopt(curl.URL, prepared_url)
    if useragent:
        curl.setopt(curl.USERAGENT, useragent)
    curl.setopt(curl.WRITEDATA, buff)
    curl.setopt(curl.FOLLOWLOCATION, False)
    # curl.setopt(curl.CONNECTTIMEOUT, timeout)
    curl.setopt(curl.TIMEOUT, timeout)
    curl.perform()
    content = buff.getvalue()
    redirect_url = curl.getinfo(curl.REDIRECT_URL)
    curl.close()
    if redirect_url is not None:
        redirect_url = to_unicode(redirect_url, 'ignore')
    return content, redirect_url

所以我对 content 的模拟不起作用，我真的不知道该怎么做。

Answer 1

我认为您创建的模拟对象比您需要的多，而且您没有正确设置返回值。例如，我会将 mock_io_string.getvalue = mock.Mock(return_value=content) 替换为 mock_io_string.getvalue.return_value = content。