如何在 Python 中为不同的 MagicMock 实例设置不同的属性? [英] How do you set different attributes for different MagicMock instances in Python?
问题描述
我想断言 say_name
是用列表 name
中的每个值调用的.
from unittest.mock 导入补丁类我的类:def __init__(self, name):self.name = 姓名def say_name(name):print('我的名字是' + 姓名)def my_func():名称 = ['foo', 'bar', 'baz']objects = [MyClass(name) for name in names][对象中对象的say_name(object.name)]@patch('my_test.say_name', spec_set=True)@patch('my_test.MyClass', spec_set=True)def test_my_func(mock_my_class, mock_say_name):名称 = ['foo', 'bar', 'baz']my_func()[mock_my_class.assert_any_call(name) for name in names]# [mock_say_name.assert_any_call(x.name) for x in xs]
如果只创建了一个 MyClass
实例,通常情况下,我可以通过设置 mock_my_class.return_value = PropertyMock(name=name)
来设置属性.
但是,在这种情况下,会创建 MyClass
的多个不同实例.
因此,此代码将抛出错误,因为 my_func
由测试人员执行,say_name
正在传递一个没有 name
属性的模拟.
因此,如何为不同的 MagicMock 实例设置不同的属性?
可以使用 side_effect
从模拟中顺序返回值:
应用于您的用例:
from types import SimpleNamespace从 unittest.mock 导入调用,补丁从 my_lib 导入 my_func@patch('my_lib.say_name')@patch('my_lib.MyClass')def test_my_func(mock_my_class, mock_say_name):FakeObj 类:经过obj1 = FakeObj()obj1.name = 'foo'obj2 = FakeObj()obj2.name = 'bar'obj3 = FakeObj()obj3.name = 'baz'mock_my_class.side_effect = [obj1, obj2, obj3]my_func()assert mock_my_class.call_args_list == [call('foo'), call('bar'), call('baz')]assert mock_say_name.call_args_list == [call('foo'), call('bar'), call('baz')]
I'd like to assert that say_name
was called with each value in the list name
.
from unittest.mock import patch
class MyClass:
def __init__(self, name):
self.name = name
def say_name(name):
print('My name is ' + name)
def my_func():
names = ['foo', 'bar', 'baz']
objects = [MyClass(name) for name in names]
[say_name(object.name) for object in objects]
@patch('my_test.say_name', spec_set=True)
@patch('my_test.MyClass', spec_set=True)
def test_my_func(mock_my_class, mock_say_name):
names = ['foo', 'bar', 'baz']
my_func()
[mock_my_class.assert_any_call(name) for name in names]
# [mock_say_name.assert_any_call(x.name) for x in xs]
If only one instance of MyClass
was created, as is usually the case, I could set the attribute by setting mock_my_class.return_value = PropertyMock(name=name)
.
However, in this case, multiple different instances of MyClass
are created.
Thus, this code will throw an error because my_func
is executed by the tester, say_name
is being passed a mock with no name
attribute.
Therefore, how can I set different attributes for different MagicMock instances?
It is possible to use side_effect
to sequentially return values from a mock:
>>> from unittest.mock import Mock
>>> m = Mock()
>>> m.side_effect = ['spam', 123, 'potato']
>>> m()
'spam'
>>> m()
123
>>> m()
'potato'
Applying to your use-case:
from types import SimpleNamespace
from unittest.mock import call, patch
from my_lib import my_func
@patch('my_lib.say_name')
@patch('my_lib.MyClass')
def test_my_func(mock_my_class, mock_say_name):
class FakeObj:
pass
obj1 = FakeObj()
obj1.name = 'foo'
obj2 = FakeObj()
obj2.name = 'bar'
obj3 = FakeObj()
obj3.name = 'baz'
mock_my_class.side_effect = [obj1, obj2, obj3]
my_func()
assert mock_my_class.call_args_list == [call('foo'), call('bar'), call('baz')]
assert mock_say_name.call_args_list == [call('foo'), call('bar'), call('baz')]
这篇关于如何在 Python 中为不同的 MagicMock 实例设置不同的属性?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!