Implemented mock support

[dmytrostriletskyi]

Hello! I frequency use ddt and mock together in my development.
I always missed some features in testing, that can make me feel more comfortable.

What is new?

I implemented decorator mockdata, that may be uses additional to common data and unpack.
This decorator says, that arguments in data values may be mock's patch object and related to it (after process it become MagicMock) attributes like return_value and side_effect (optional).

Usage

Simple example with arguments.

@data(
    [patch('application.utils.requests.get'), '/api/registration/', 'get'],
    [patch('application.utils.requests.post'), '/api/registration/', 'post']
)
@unpack
@mockdata
def test_registration_few_types(self, mock_request, url, http_request_type):
    register_user(http_request_type)
    mock_request.assert_called_with(url)

Another one.

@data(
    patch('application.utils.registration'), 
    patch('application.utils.authorization')
    patch('application.utils.send_statistic')
)
@unpack
@mockdata
def test_api_flow(self, mock_api_endpoint_func):
    make_api_flow()
    mock_api_endpoint_func.assert_called()

Example, where you can see, that Mock applied side_effect in background and you get result right away without applying it by yourself.

@data(
    {'patch': patch('application.utils.get_publication'), 'side_effect': KeyError()},
)
@unpack
@mockdata
def test_no_publication(self, mock_get_publication):
    result = get_publication('California')
    self.assertEqual('No publications yet.', result)

[codecov-io]

Codecov Report

Merging #53 into master will decrease coverage by 2.17%.
The diff coverage is 90.62%.

@@            Coverage Diff             @@
##           master      #53      +/-   ##
==========================================
- Coverage     100%   97.82%   -2.18%     
==========================================
  Files           1        1              
  Lines         107      138      +31     
==========================================
+ Hits          107      135      +28     
- Misses          0        3       +3

Impacted Files	Coverage Δ
ddt.py	97.82% <90.62%> (-2.18%)	⬇️

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[txels]

Hey thanks for this!
Apologies for the super-late review, I'm not sure how this PR escaped my radar for so long.

Without having yet looked into the details, this seems like a good contribution. Would you mind updating the documentation as well? I will review the implementation details.

[txels]

Have you considered using mockdata as a replacement for data (as we do with file_data) rather than an annotation-style decorator? I think it might be a bit more consistent with how things are done at the moment. What do you see as pros and cons of that approach?

[dmytrostriletskyi]

@txels, heyo!

I think you are rigth with file_data approach for mock instead off additional @mock decorator to @data. Sorry, that I did not use to investigate package better to provide suitable way at the very beginning.

Let me time to refactor my stuff: I need remember ddt behave, create pretty code to corresponding approach (mock_data) and tests.

Thanks you a lot for payin attention on my pull request.

[wswld]

@dmytrostriletskyi Hi, are you still interested in this?

[wswld]

Continuing this effort in another PR to fix and clean up some stuff. Closing this.