[英]proper way python mock __init__() method that returns a fake class
Trying to mock out calls to pyazure library for django testing, but I can't figure out how to mock out the PyAzure class constructor so that it doesn't cause a TypeError. 试图模拟调用pyazure库进行django测试,但我无法弄清楚如何模拟PyAzure类构造函数,以便它不会导致TypeError。 Is there a better way to approach mocking out an access library that generates a connection object?
有没有更好的方法来模拟生成连接对象的访问库?
Anything I've tried other than None generates a TypeError, which means I can't really even begin to test any of the PyAzure connection methods with actual return values. 我尝试过的除None之外的任何东西都会产生TypeError,这意味着我甚至无法开始使用实际返回值来测试任何PyAzure连接方法。 What is the best way to replace a working class with a fake class using mock?
使用mock替换假类的最佳方法是什么?
Test Error: 测试错误:
======================================================================
ERROR: test_management_certificate_connect (azure_cloud.tests.ViewsTest)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/Users/bschott/Source/django-nimbis/apps/azure_cloud/tests.py", line 107, in test_management_certificate_connect
self.cert1.connect()
File "/Users/bschott/Source/django-nimbis/apps/azure_cloud/models.py", line 242, in connect
subscription_id=self.subscription.subscription_id)
TypeError: __init__() should return None, not 'FakeAzure'
----------------------------------------------------------------------
tests.py: tests.py:
class ViewsTest(TestCase):
def setUp(self):
...
self.cert1 = ManagementCertificate.objects.create(
name="cert1",
subscription=self.subscription1,
management_cert=File(open(__file__), "cert1.pem"),
owner=self.user1)
...
class FakeAzure(object):
""" testing class for azure """
def list_services(self):
return ['service1', 'service2', 'service3']
def list_storages(self):
return ['storage1', 'storage2', 'storage3']
@mock.patch.object(pyazure.PyAzure, '__init__')
def test_management_certificate_connect(self, mock_pyazure_init):
mock_pyazure_init.return_value = self.FakeAzure()
self.cert1.connect()
assert mock_pyazure_init.called
models.py models.py
class ManagementCertificate(models.Model):
# support connection caching to azure
_cached_connection = None
def connect(self):
"""
Connect to the management interface using these credentials.
"""
if not self._cached_connection:
self._cached_connection = pyazure.PyAzure(
management_cert_path=self.management_cert.path,
subscription_id=self.subscription.subscription_id)
logging.debug(self._cached_connection)
return self._cached_connection
You seem to have a misconception about what __init__()
does. 您似乎对
__init__()
含义存在误解。 Its purpose is to initialise an instance that was already created earlier. 其目的是初始化先前已创建的实例。 The first argument to
__init__()
is self
, which is the instance, so you can see it was already allocated when __init__()
is called. __init__()
的第一个参数是self
,它是实例,因此您可以看到在调用__init__()
时已经分配了它。
There is a method __new__()
that is called before __init__()
to create the actual instance. 在
__init__()
之前调用了一个方法__new__()
__init__()
来创建实际的实例。 I think it would be much easier, though, to replace the whole class by a mock class, instead of mocking single methods. 但是,我认为用模拟类替换整个类会更容易,而不是模仿单个方法。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.