How can I hide my stack frames in a TestCase subclass?

[Manuel Pégourié-Gonnard]

Peter Otten scripsit :

> Manuel Pégourié-Gonnard wrote:
>
>> Peter Otten scripsit :
>> 
>>> __unittest = True
>>>
>> Hum, is it documented somewhere? I can't find it in the doc. Also, I'm
>> curious to know what kind of magic it's using.
>
> I took advantage of the fact that Python is open source and had a look into 
> the source code ;)
>
Fair enough.

However, there was an implied question in the "documented" part: can
we rely on it? Isn't it considered an implementation detail (names
starting with underscores)?

> $ cd /usr/lib/python2.7/unittest
> $ grep frame *.py -C2
> ...
> result.py-
> result.py-    def _is_relevant_tb_level(self, tb):
> result.py:        return '__unittest' in tb.tb_frame.f_globals
> result.py-
> ...
>
> $ grep _is_relevant_tb_level *.py -C5
> result.py-
> result.py-    def _exc_info_to_string(self, err, test):
> result.py-        """Converts a sys.exc_info()-style tuple of values into a 
> string."""
> result.py-        exctype, value, tb = err
> result.py-        # Skip test runner traceback levels
> result.py:        while tb and self._is_relevant_tb_level(tb):
> result.py-            tb = tb.tb_next
> result.py-
> ...
>
> And so on. I actually used an editor, not grep -- but you get the idea.

Sure, thanks.

-- 
Manuel Pégourié-Gonnard - http://people.math.jussieu.fr/~mpg/