Re: [matplotlib-devel] Problem adding a new test

I've committed support for comparing SVG files using Inkscape and 
verifying them against the official SVG DTD using xmllint.

Michael Droettboom wrote:
> Andrew Straw wrote:
>   
>> Done in r7863. To make use of it, do something like the following patch
>> (and don't forget to delete the baseline .pdf files from the repository):
>>
>> -@image_comparison(baseline_images=['simplify_curve'])
>> +@image_comparison(baseline_images=['simplify_curve'],extensions=['png'])
>>   
>>     
> Great!
>   
This is a nice feature.  However, in hindsight, I may not use it right 
away -- I actually found a bug in the SVG backend using one of the tests 
I assumed would only affect the Agg backend.  :)

  

A couple more comments about the test framework -- which has already 
paid for itself ten times over.  In Numpy (and a number of local Python 
projects), I can 'cd' to the tests directory and do something like:

   nosetests test_simplification.py:test_hatch_simplify

and run on particular test, or a single file of tests.  It's a huge time 
saver when trying to fix a bug.  However, with matplotlib I get:

 > nosetests test_simplification.py
E
======================================================================
ERROR: Failure: ImportError (cannot import name cbook)
----------------------------------------------------------------------
Traceback (most recent call last):
  File 
"/wonkabar/data1/usr/lib/python2.5/site-packages/nose-0.11.1-py2.5.egg/nose/loader.py", 
line 379, in loadTestsFromName
    addr.filename, addr.module)
  File 
"/wonkabar/data1/usr/lib/python2.5/site-packages/nose-0.11.1-py2.5.egg/nose/importer.py", 
line 39, in importFromPath
    return self.importFromDir(dir_path, fqname)
  File 
"/wonkabar/data1/usr/lib/python2.5/site-packages/nose-0.11.1-py2.5.egg/nose/importer.py", 
line 86, in importFromDir
    mod = load_module(part_fqname, fh, filename, desc)
  File 
"/wonkabar/data1/builds/matplotlib/build/lib.linux-i686-2.5/matplotlib/tests/test_simplification.py", 
line 4, in <module>
    import matplotlib.pyplot as plt
  File 
"/wonkabar/data1/builds/matplotlib/build/lib.linux-i686-2.5/matplotlib/pyplot.py", 
line 6, in <module>
    from matplotlib import docstring
  File 
"/wonkabar/data1/builds/matplotlib/build/lib.linux-i686-2.5/matplotlib/docstring.py", 
line 1, in <module>
    from matplotlib import cbook
ImportError: cannot import name cbook

----------------------------------------------------------------------
Ran 1 test in 0.009s

FAILED (errors=1)


I suspect this is something peculiar to how matplotlib gets imported.

Also, I have a quad-core machine, so I put this in my .noserc, which 
will run tests in parallel:

   [nosetests]
   processes=4

Unfortunately, due to however matplotlib is delegating to nose, this 
doesn't seem to get picked up.

I don't know if I'll get a chance to look at these things right away, 
but thought I'd share in case the solutions are obvious to anyone else 
(which I know isn't good form, but hey... ;)

Cheers,
Mike

-- 
Michael Droettboom
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA