Re: [Discuss-gnuradio] importing modules in tests

[Ben Reynwar]

On Tue, Jun 21, 2011 at 5:53 PM, Tom Rondeau <address@hidden> wrote:
> On Tue, Jun 21, 2011 at 8:13 PM, Ben Reynwar <address@hidden> wrote:
>>
>> Hi all,
>>
>> I'm having difficulty working out how to import modules when doings
>> tests, since for the tests the python code that is used is the
>> non-installed version, and so the package/subpackage hierarchy of the
>> various python folders is not in place.
>>
>> For example if I am creating a test for gr-trellis, but I want to
>> import features from gr-digital, I cannot simply use "from
>> gnuradio.digital import xxx".
>>
>> Is there a good reason why the tests can't simply use the installed
>> version of gnuradio?  It seems like this would make everything
>> simpler.
>>
>> Cheers,
>> Ben
>
> It's because you really want to test off of what you are _about_ to install,
> not what's already installed. This is especially problematic if you haven't
> done a 'make install,' yet.
> The QA code in various packages in GNU Radio should show you how to grab the
> stuff locally.
> Let me know if you need more specific help. I haven't done anything with the
> QA code in gr-trellis, but I've worked on it elsewhere.
> Tom
>

For a test in gr-trellis, I can access the trellis and gnuradio.gr
subpackages fine since they have been added to PYTHONPATH by
run_tests.sh.  To get access to gnuradio.digital I would need to
modify run_tests.sh.

I think a slightly more elegant solution would be to have a
testing_pydir/gnuradio/__init__.py file somewhere.  This __init__.py
file would then point to the locations of the folders corresponding to
the various subpackages.  When doing testing PYTHONPATH could simply
point to testing_pydir and then "from gnuradio import gr, trellis,
digital" would work without any problems.  We would have two versions
of the top level __init__.py file: one in
gnuadio-core/src/python/gnuradio which is installed, and one in
testing_pydir/gnuradio which is used when testing.

An advantage of this would be that the qa tests would work when tested
through "make check", and would also work if run as stand-alone
scripts e.g. "python qa_xxx.py".

Ben