[py-dev] RFC: draft new resource management API (v1)

[holger krekel]

On Thu, Jun 28, 2012 at 08:15 +0000, holger krekel wrote:
> I am still fine to consider e. g. the introduction of a pytest.current
> namespace.  It could lead to make setup_X methods more powerful::
> 
>     import pytest
>     def setup_module():  # pytest accepts it to keep nose compat
>         db = pytest.current.modulenode.getresource("db")
> 
> The "current" namespace could be set by the respective node setup
> methods.  For classes it's the same idea::
> 
>     class TestClass:
>         def setup_class(cls):
>             cls.db = pytest.current.classnode.getresource("db")
> 
> Due to the non-declarative nature of this approach, however, i don't
> see a way to rerun the testclass with multiple "db" instances.

Actually i see a way :)

    @pytest.mark.uses_resource("db")
    class TestClass:
        ...

This would signal pytest that this class is (somehow) using
the parameter "db" and thus collect multiple variations if the
resource is parametrized at register_factory time.  Of course,
plugins such as pytest-django would be able to declare this resource
usage automatically, reducing boilerplate for test writers.

What do you think?

holger



> On a side note, many Java programmers have gone from the old JUnit
> approach to TestNG, see the wikipedia entries.  py.test rather
> goes for similar ideas as TestNG.
> 
> best,
> holger
> 
> > 
> > >> Also, I realised this API provides for what is probably most of the
> > >> cases of where I want dynamic resources:
> > >>
> > >> def pytest_setup_init(session):
> > >>     for item in my_item_generator():
> > >>         session.register_resource_factory(item.name, item)
> > >
> > > Not sure i understand this idea.  Is it intended as a mixture of
> > > collection (my_item_generator) and setup (as the hook name suggests)?
> > 
> > My bad for writing a bad example, I shouldn't have used the word
> > "item" in there.  Anyway the main point is that thanks to
> > .register_resource_factory() taking the name of the resource as an
> > argument I believe most, if not all, the cases where I wanted to
> > create funcargs/resources without knowing what they where beforehand
> > are solved.
> > 
> > 
> > Regards,
> > Floris
> > 
> > 
> > -- 
> > Debian GNU/Linux -- The Power of Freedom
> > www.debian.org | www.gnu.org | www.kernel.org
> > 
>