Suspicious gaps in Nose coverage

Question

I'm using Nose with Django (and django-nose), and I get a very odd coverage report:

$ python3 manage.py test lists
nosetests lists --with-coverage --cover-package=lists,superlists --verbosity=1
Creating test database for alias 'default'...
............
Name                                          Stmts   Miss  Cover   Missing
---------------------------------------------------------------------------
lists.py                                          0      0   100%
lists\admin.py                                    0      0   100%
lists\migrations\0001_initial.py                  5      0   100%
lists\migrations\0002_item_text.py                5      0   100%
lists\migrations\0003_list.py                     5      0   100%
lists\migrations\0004_item_list.py                5      0   100%
lists\migrations\0005_auto_20151117_1835.py       5      0   100%
lists\migrations.py                               0      0   100%
lists\models.py                                   6      6     0%   1-12
lists\urls.py                                     3      0   100%
lists\views.py                                   23      0   100%
superlists.py                                     0      0   100%
superlists\settings.py                           19     19     0%   14-113
superlists\urls.py                                5      0   100%
---------------------------------------------------------------------------
TOTAL                                            81     25    69%
----------------------------------------------------------------------
Ran 12 tests in 0.073s

My settings are configured with:

TEST_RUNNER = 'django_nose.NoseTestSuiteRunner'

NOSE_ARGS = [
    '--with-coverage',
    '--cover-package=lists,superlists',
]

And those obviously are read as it manages to apply the arguments and looks at my lists and superlists (I'm doing the TDD with Python book) apps just fine. For some reason, however, it says it didn't cover any of the settings.py file or my lists/models.py; very simple classes that just have some field definitions, no functions, no methods. If a 'root-level' class is in a module and is imported, all its class-attribute and method signatures (def x(...): lines) are executed, successfully, otherwise it would crash immediately.

The settings file must be executed, otherwise Django wouldn't even run. Why is the coverage report that and the models as misses?

score 0 · Answer 1 · edited May 23 '17 at 12:33

The most possible answer is that django-nose fires coverage after your settings file is imported (because the manage.py test command itself runs the django setup code before running the tests). Therefore any code evaluated during this setup process is not included in the coverage results.

You might want to have a look at this answer on a related question for a more detailed explanation. Hope this helps!

Suspicious gaps in Nose coverage

1 Answers1