[PATCH 2 of 5] ui: add a 'stacklevel' argument to 'develwarn'

[Pierre-Yves David]

On 12/07/2015 06:07 AM, Yuya Nishihara wrote:
> On Sun, 06 Dec 2015 12:45:12 -0800, Pierre-Yves David wrote:
>> # HG changeset patch
>> # User Pierre-Yves David <pierre-yves.david at fb.com>
>> # Date 1449385533 28800
>> #      Sat Dec 05 23:05:33 2015 -0800
>> # Node ID eca257699f241e8490ff79a0a2e869fd241ad596
>> # Parent  847325e9c631e096019eb97a882cba0cb91cedb8
>> # EXP-Topic deprecationwarning
>> # Available At http://hg.netv6.net/marmoute-wip/mercurial/
>> #              hg pull http://hg.netv6.net/marmoute-wip/mercurial/ -r eca257699f24
>> ui: add a 'stacklevel' argument to 'develwarn'
>>
>> This allows helper functions (like deprecation warning) to prepare a devel
>> warning for higher up in the stack. The argument is named after the one in the
>> Python's 'warning,warn' function.
>>
>> diff --git a/mercurial/ui.py b/mercurial/ui.py
>> --- a/mercurial/ui.py
>> +++ b/mercurial/ui.py
>> @@ -1042,19 +1042,25 @@ class ui(object):
>>           ui.write(s, 'label') is equivalent to
>>           ui.write(ui.label(s, 'label')).
>>           '''
>>           return msg
>>
>> -    def develwarn(self, msg):
>> -        """issue a developer warning message"""
>> +    def develwarn(self, msg, stacklevel=0):
>> +        """issue a developer warning message
>> +
>> +        Use 'stacklevel' to report the offender some layers further up in the
>> +        stack.
>> +        """
>>           msg = 'devel-warn: ' + msg
>> +        stacklevel += 2 # get out of develwarn
>
> I might be paranoid, but if we copy the behavior of warnings.warn, the default
> stacklevel should be 1.
>
>     stacklevel=0: develwarn()
>     stacklevel=1: caller of develwarn()
>     stacklevel=2: wrapper function that calls develwarn()
>
> https://docs.python.org/2.7/library/warnings.html#warnings.warn

ha, true, will send a V2

>
>>           if self.tracebackflag:
>> -            util.debugstacktrace(msg, 2, self.ferr, self.fout)
>> +            util.debugstacktrace(msg, stacklevel, self.ferr, self.fout)
>>           else:
>>               curframe = inspect.currentframe()
>> -            calframe = inspect.getouterframes(curframe, 2)
>> -            self.write_err('%s at: %s:%s (%s)\n' % ((msg,) + calframe[2][1:4]))
>> +            calframe = inspect.getouterframes(curframe, stacklevel)
>
> getouterframes() doesn't need stacklevel. The second argument is the number of
> lines to be returned as a context.


good catch.


-- 
Pierre-Yves David