[Sqlalchemy-tickets] [sqlalchemy] #2905: Attempting to use a partial() instance as an event listener causes infinite recursion

[sqlalchemy <mi...@zz...>]

#2905: Attempting to use a partial() instance as an event listener causes infinite
recursion
-----------------------+-----------------------------------------
 Reporter:  agronholm  |           Owner:  zzzeek
     Type:  defect     |          Status:  new
 Priority:  medium     |       Milestone:
Component:  utils      |        Severity:  no triage selected yet
 Keywords:             |  Progress State:  awaiting triage
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 I had this line in my app fail due to infinite recursion:
 {{{
 event.listen(session, 'after_commit', partial(self.publish_events,
 models=tuple(models_changed)))
 }}}
 This is a regression from 0.8.4. I haven't tested with 0.9.0b1.

 The simplest way to reproduce this is:
 {{{
 >>> from functools import partial
 >>> from sqlalchemy.util import get_callable_argspec
 >>> p = partial(print, 'b')
 >>> get_callable_argspec(p)
 ....
   File "/home/alex/virtualenv/triancore/lib/python3.3/site-
 packages/sqlalchemy/util/langhelpers.py", line 272,
 in get_callable_argspec
     return get_callable_argspec(fn.__call__)
   File "/home/alex/virtualenv/triancore/lib/python3.3/site-
 packages/sqlalchemy/util/langhelpers.py", line 264,
 in get_callable_argspec
     if isinstance(fn, types.FunctionType):
 RuntimeError: maximum recursion depth exceeded while calling a Python
 object
 }}}

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Ticket URL: <http://www.sqlalchemy.org/trac/ticket/2905>
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