python - 使用python和mock模拟ReviewBoard第三方库

Question

我使用 ReviewBoard API 库，今天我将代码移至单独的类，并希望通过一些测试来覆盖逻辑。我了解模拟和测试，但显然我对 python 及其库没有太多经验。这是真正的代码块:

<!-- language: python -->
from rbtools.api.client import RBClient

class ReviewBoardWrapper():

    def __init__(self, url, username, password):
        self.url = url
        self.username = username
        self.password = password
        pass

    def Connect(self):
        self.client = RBClient(self.url, username=self.username, password=self.password)
        self.root = self.client.get_root()
        pass

我想断言初始化以及调用 get_root() 方法。以下是我尝试实现这一目标的方法:

<!-- language: python -->
import unittest
import mock

from module_base import ReviewBoardWrapper as rb

class RbTestCase(unittest.TestCase):

    @mock.patch('module_base.RBClient')
    @mock.patch('module_base.RBClient.get_root')
    def test_client_connect(self, mock_client, mock_method):
        rb_client = rb('', '', '')
        rb_client.Connect()
        self.assertTrue(mock_method.called)
        self.assertTrue(mock_client.called)

这是我遇到的错误:

$ python -m unittest module_base_tests
F.
======================================================================
FAIL: test_client_connect (module_base_tests.RbTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/mock/mock.py", line 1305, in patched
    return func(*args, **keywargs)
  File "module_base_tests.py", line 21, in test_client_connect
    self.assertTrue(mock_client.called)
AssertionError: False is not true

----------------------------------------------------------------------
Ran 2 tests in 0.002s

FAILED (failures=1)

我做错了什么？我是否正确模拟了导入库的“本地副本”？问题是否完全出在不同的领域？

我也尝试过这样做:

@mock.patch('module_base.RBClient.__init__')

和/或这个:

self.assertTrue(mock_client.__init__.called)

Answer 1

在您帖子的示例中，模拟的顺序是相反的:

test_client_connect(self, mock_client, mock_method)

客户端实际上被模拟为第二个参数，方法调用被模拟为第一个参数。

但是，为了正确模拟客户端，您需要模拟客户端调用的返回值。模拟返回值并对返回值进行断言的示例如下:

class RbTestCase(unittest.TestCase):                                                                                                                                                                        

    @mock.patch('module_base.RBClient')                                                                                                                                                                     
    def test_client_connect(self, mock_client):                                                                                                                                                             
        client = mock.MagicMock()                                                                                                                                                                           
        mock_client.return_value = client                                                                                                                                                                   
        rb_client = rb('', '', '')                                                                                                                                                                          
        rb_client.Connect()                                                                                                                                                                                 
        self.assertTrue(client.get_root.called)                                                                                                                                                             
        self.assertTrue(mock_client.called)