[Python-ideas] SealedMock proposal for unittest.mock

[Julien Duponchelle]

Perhaps you can set via configure_mock. This will prevent conflict with
existing code.

Julien

On Thu, Jun 1, 2017 at 2:17 PM Victor Stinner <victor.stinner at gmail.com>
wrote:

> A stricter mock object cannot be a bad idea :-) I am not sure about your
> proposed API: some random code may already use this attribute. Maybe it can
> be a seal (mock) function which sets a secret attribute with a less common
> name?
>
> Yeah, please open an issue on bugs.python.org ;-)
>
> Victor
>
>
> Le 29 mai 2017 11:33 PM, "Mario Corchero" <mariocj89 at gmail.com> a écrit :
>
>> Hello Everyone!
>>
>> First time writing to python-ideas.
>>
>> *Overview*
>> Add a new mock class within the mock module
>> <https://github.com/python/cpython/blob/master/Lib/unittest/mock.py>,
>> SealedMock (or RestrictedMock) that allows to restrict in a dynamic and
>> recursive way the addition of attributes to it. The new class just defines
>> a special attribute "sealed" which once set to True the behaviour of
>> automatically creating mocks is blocked, as well as for all its "submocks".
>> See sealedmock
>> <https://github.com/mariocj89/sealedmock/blob/master/README.md>. Don't
>> focus on the implementation, it is ugly, it would be much simpler within
>> *mock.py*.
>>
>> *Rationale*
>> Inspired by GMock
>> <https://github.com/google/googletest/tree/master/googlemock> RestrictedMock,
>> SealedMock aims to allow the developer to define a narrow interface to the
>> mock that defines what the mocks allows to be called on.
>> The feature of mocks returning mocks by default is extremely useful but
>> not always desired. Quite often you rely on it only at the time you are
>> writing the test but you want it to be disabled at the time the mock is
>> passed into your code, that is what SealedMock aims to address.
>>
>> This solution also prevents user errors when mocking incorrect paths or
>> having typos when calling attributes/methods of the mock.
>> We have tried it internally in our company and it gives quite a nicer
>> user experience for many use cases, specially for new users of mock as it
>> helps out when you mock the wrong path.
>>
>> *Alternatives*
>>
>>    - Using auto_spec/spec is a possible solution but removes flexibility
>>    and is rather painful to write for each of the mocks and submocks being
>>    used.
>>    - Leaving it outside of the mock.py as it is not interesting enough.
>>    I am fine with it :) just proposing it in case you think otherwise.
>>    - Make it part of the standard Mock base class. Works for me, but I'd
>>    concerned on how can we do it in a backward compatible way. (Say someone is
>>    mocking something that has a "sealed" attribute already).
>>
>> Let me know what you think, happy to open a enhancement in
>> https://bugs.python.org/ and send a PR.
>>
>> Regards,
>> Mario
>>
>> _______________________________________________
>> Python-ideas mailing list
>> Python-ideas at python.org
>> https://mail.python.org/mailman/listinfo/python-ideas
>> Code of Conduct: http://python.org/psf/codeofconduct/
>>
>> _______________________________________________
> Python-ideas mailing list
> Python-ideas at python.org
> https://mail.python.org/mailman/listinfo/python-ideas
> Code of Conduct: http://python.org/psf/codeofconduct/
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-ideas/attachments/20170601/b59f9346/attachment-0001.html>