[Zope-dev] Re: [zope.testing.doctest] a nasty surprise

[Balazs Ree]

On Thu, 10 Apr 2008 11:50:35 -0400, Benji York wrote:

> Dieter Maurer wrote:
>> As the community (apparently) strongly favors "doctest" over
>> "unittest", I wrote my first test based on "zope.testing.doctest". And
>> promptly, I was badly surprised....
>> 
>> In order to analyse a difficult problem, I added "from dm.pdb import
>> zpdb; zpdb.set_trace()" in the doctest ("dm.pdb.zpdb" is my Zope aware
>> PDB extension)
> 
> The standard PDB works fine.  I'm sure you're extended version can be
> tweaked to as well.

I have similar issues with ipdb. - similar in sense that I cannot use it 
when running from doctests.

ipdb is a lightweight component that enables entering ipython when 
"import ipdb; ipdb.set_trace()" is called. Those of you that use ipython 
and also develop with doctests a lot, will understand why it would be a 
nice to have also from doctests.

In case of ipdb I had no parameters problem like Dieter encountered with 
zpdb, however I observed that the doctest runner needs to redirect input 
and output while running tests, which are specifically routed back to 
stdin and stdout while pdb.set_trace is entered, to enable interactivity. 
This is done by monkeypatching pdb if I remember well. But the same does 
not happen with ipdb, of course.

So, my conclusion is that while doctests work well with the standard pdb, 
any alternate debugger must be supported explicitely (by changing the 
doctest code). As with ipdb, this may be the case with zpdb as well.

Best wishes


-- 
Balazs Ree