=========================
Tuesday, January 13, 2015
=========================

Moved the content of :lino:`/dev/mixins` to the docstrings in
:mod:`lino.core.model` and :mod:`lino.mixins`.

Fixed :ticket:`7`. When a new user had been created through the web
interface, it was not possible to change their password.


ValueError: Attempted relative import in non-package
----------------------------------------------------

Then I converted the content of `/dev/ml/users` to the
:mod:`lino.modlib.users` API.  

Since this is a tested document, I changed two lines in
:srcref:`/tests/__init__.py`. Basically I replaced::

   self.run_simple_doctests("docs/dev/ml/users.rst")

with::

    self.run_simple_doctests("lino/modlib/users/models.py")

This change caused a :message:`ValueError: Attempted relative import
in non-package` at the line::

  from .mixins import UserProfiles

I've had this problem before, and this time I explored the reason for
it. 

It comes from :mod:`atelier.doctest_utf8` where some code which I did
not write (I copied it from Python 2.7's ``doctest`` module) does a
special handling if a file ends with :file:`.py`. And a comment for
this treatment says::

    # It is a module -- insert its dir into sys.path and try to
    # import it. If it is part of a package, that possibly
    # won't work because of package imports.

And this comment is still there in the doctest module of Python 3.


And of course I am not the first to stumble over this problem.  See
`Doctest and relative imports
<https://stackoverflow.com/questions/4047227/doctest-and-relative-imports>`_
where Jason Scheirer advises:

    I would get rid of the relative imports, many Python style guides
    strongly discourage them, most forbid them.

But even when I do this, the import fails because Django is special:
you cannot import a :xfile:`models.py` module if your
`DJANGO_SETTINGS_MODULE` is not set.  So I moved these tests to a
separate new document :lino:`/dev/users`. A topic which anyway has
serious lacks of documentation.