Saturday, June 10, 2017

I continued to restore the test suites after the changes for #1329.

The most important consequence of these changes is that Lino applications now need our patched Django version until Django fixes Django ticket 20313. And let’s hope that they fix them in a way as Lino needs them to be fixed. So I started to write a pull request. For this I followed the Writing your first patch for Django tutorial, then forked Django on GitHub, then re-did my changes into that repository.

A strange behaviour

So I now have a local copy of my Django fork repository, which I installed into my default working environment. using:

pip -e /home/luc/repositories/django

in a new branch ticket_20313,

That

I changed the install_requires to say 'django<2' as requirement. The current version is 1.11.3.dev20170609164846 (from repository) which satisfies that dependency:

$ python -c "import django; print django.__version__"

These setting seem to have caused a strange behaviour when I try to run a specific test (tests.SpecsTests.test_care in below example) : Invoking py.test -k test_care works as expected, but python setup.py test -s tests.SpecsTests.test_care doesn’t. It says:

$ python setup.py test -s tests.SpecsTests.test_care
running test
Searching for django<=1.11
Reading https://pypi.python.org/simple/django/
Downloading https://pypi.python.org/packages/79/43/ed9ca4d69f35b5e64f2ecad73f75a8529a9c6f0d562e5af9a1f65beda355/Django-1.11.tar.gz#md5=5008d266f198c2fe761916139162a0c2
Best match: Django 1.11
Processing Django-1.11.tar.gz
...
Installed /media/dell1tb/work/book/.eggs/Django-1.11-py2.7.egg
...
test_care (tests.SpecsTests) ... FAIL

That is, setuptools (unlike py.test) seems to believe that version 1.11.3.dev20170609164846 does not satisfy the django<2 requirement.

The problem disappeared when I did:

$ pip uninstall lino
$ go lino
$ pip install -e .

About Django ticket 20313

Here is a summary of my changes (meanwhile obsoleted):

  • In django/contrib/auth/base_user.py I defined a new classmethod on the AbstractUser model:

    @classmethod
def get_anonymous_user(cls):
    """Return an instance of AnonymousUser. Alternative implementations
    for AUTH_USER_MODEL may override this to use an alternative
    AnonymousUser class or add custom initialization.

    """
    return AnonymousUser()

  • In several places (django/contrib/auth/__init__.py) I replaced code like the following:

    from django.contrib.auth.models import AnonymousUser
request.user = AnonymousUser()

    by code like this:

    from django.contrib.auth import get_user_model
request.user = get_user_model().get_anonymous_user()

  • In django/contrib/auth/backends.py I moved the import of the Permission class from the global scope into the two local scopes which use it. This is necessary because Lino’s lino.modlib.users package defines an alternative User model and no models Permission and Group. As long as the import statement is on the global scope, Django complains about XXX when I try to import it.