1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/python/mock-1.0.0/html/_sources/sentinel.txt Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,58 @@
1.4 +==========
1.5 + Sentinel
1.6 +==========
1.7 +
1.8 +
1.9 +.. currentmodule:: mock
1.10 +
1.11 +.. testsetup::
1.12 +
1.13 + class ProductionClass(object):
1.14 + def something(self):
1.15 + return self.method()
1.16 +
1.17 + class Test(unittest2.TestCase):
1.18 + def testSomething(self):
1.19 + pass
1.20 + self = Test('testSomething')
1.21 +
1.22 +
1.23 +.. data:: sentinel
1.24 +
1.25 + The ``sentinel`` object provides a convenient way of providing unique
1.26 + objects for your tests.
1.27 +
1.28 + Attributes are created on demand when you access them by name. Accessing
1.29 + the same attribute will always return the same object. The objects
1.30 + returned have a sensible repr so that test failure messages are readable.
1.31 +
1.32 +
1.33 +.. data:: DEFAULT
1.34 +
1.35 + The `DEFAULT` object is a pre-created sentinel (actually
1.36 + `sentinel.DEFAULT`). It can be used by :attr:`~Mock.side_effect`
1.37 + functions to indicate that the normal return value should be used.
1.38 +
1.39 +
1.40 +Sentinel Example
1.41 +================
1.42 +
1.43 +Sometimes when testing you need to test that a specific object is passed as an
1.44 +argument to another method, or returned. It can be common to create named
1.45 +sentinel objects to test this. `sentinel` provides a convenient way of
1.46 +creating and testing the identity of objects like this.
1.47 +
1.48 +In this example we monkey patch `method` to return
1.49 +`sentinel.some_object`:
1.50 +
1.51 +.. doctest::
1.52 +
1.53 + >>> real = ProductionClass()
1.54 + >>> real.method = Mock(name="method")
1.55 + >>> real.method.return_value = sentinel.some_object
1.56 + >>> result = real.method()
1.57 + >>> assert result is sentinel.some_object
1.58 + >>> sentinel.some_object
1.59 + sentinel.some_object
1.60 +
1.61 +
