Dummy object in Python

Question

Is it possible to create a "stupid" dummy object in Python that will always no-op and never throw an error, no matter how is called or otherwise manipulated?

The use case for this is when there's an object that is used to create side effects in the normal case, but if run in a different environment (suppose, during development) should not do anything and fail silently.

try:
    o = Obj()
except ImportError:
    # we're in development mode
    o = DummyObj()

o.doStuff()  # should work or fail silently

Answer 1

Try using Mock objects. Any call made on a Mock object will return another Mock object.

For example:

>>> from mock import Mock
>>> test = Mock()
>>> test.doStuff()
<Mock name='mock.doStuff()' id='4373729360'>
>>> test2 = test.doStuff
>>> test2
<Mock name='mock.doStuff' id='4373693712'>
>>> test2()
<Mock name='mock.doStuff()' id='4373729360'>

As shown here, it is consistent - calling doStuff() multiple times returns the same Mock, and if you call the Mock created by mock.doStuff it will return the same Mock as doStuff().

Mock objects are commonly used in unit tests, so there is a lot more that you can do with them than what I've shown here. Read more here if you are interested.