Better support for missing __name__ in frame traversal

[Callek]

In my own code, I got a new traceback for this issue (meant to be fixed in release of 15.1.0)

With some DEBUG prints sprinkled in, I was able to see that f.f_frame.has_key("__name__") was True, however f.f_frame.get("__name__", "?") would still return None thus skipping that default choice.

Per python docs, foo.get("whatever") already has a default value of None so simply mixing them with "or" will achieve the desired goal here in all existing cases, as well as fix my own case.

For reference the full traceback I had:

Traceback (most recent call last):
  File "/data/www/relengapi/celery", line 81, in <module>
    load_entry_point('celery', 'console_scripts', 'celery')()
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/__main__.py", line 30, in main
    main()
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bin/celery.py", line 81, in main
    cmd.execute_from_commandline(argv)
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bin/celery.py", line 769, in execute_from_commandline
    super(CeleryCommand, self).execute_from_commandline(argv)))
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bin/base.py", line 307, in execute_from_commandline
    return self.handle_argv(self.prog_name, argv[1:])
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bin/celery.py", line 761, in handle_argv
    return self.execute(command, argv)
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bin/celery.py", line 693, in execute
    ).run_from_argv(self.prog_name, argv[1:], command=argv[0])
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bin/worker.py", line 179, in run_from_argv
    return self(*args, **options)
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bin/base.py", line 270, in __call__
    ret = self.run(*args, **kwargs)
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bin/worker.py", line 212, in run
    state_db=self.node_format(state_db, hostname), **kwargs
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/worker/__init__.py", line 100, in __init__
    self.setup_instance(**self.prepare_args(**kwargs))
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/worker/__init__.py", line 141, in setup_instance
    self.blueprint.apply(self, **kwargs)
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bootsteps.py", line 209, in apply
    self._debug('Preparing bootsteps.')
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/celery/bootsteps.py", line 272, in _debug
    return debug(_pre(self, msg), *args)
  File "/usr/lib/python2.7/logging/__init__.py", line 1128, in debug
    self._log(DEBUG, msg, args, **kwargs)
  File "/data/www/relengapi/celery", line 62, in new_log
    old_log(self, level, msg, args, exc_info=None, extra=extra)
  File "/usr/lib/python2.7/logging/__init__.py", line 1249, in _log
    fn, lno, func = self.findCaller()
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/structlog/stdlib.py", line 32, in findCaller
    f, name = _find_first_app_frame_and_name(['logging'])
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/structlog/_frames.py", line 41, in _find_first_app_frame_and_name
    while any(name.startswith(i) for i in ignores):
  File "/data/www/relengapi/virtualenv/lib/python2.7/site-packages/structlog/_frames.py", line 41, in <genexpr>
    while any(name.startswith(i) for i in ignores):
AttributeError: 'NoneType' object has no attribute 'startswith'

If this patch is accepted, I would appreciate a new structlog release, sooner than later.

[codecov-io]

Current coverage is 100.00%

Merging #58 into master will not affect coverage as of 78dc9c1

@@            master     #58   diff @@
======================================
  Files           12      12       
  Stmts          593     593       
  Branches        68      68       
  Methods          0       0       
======================================
  Hit            593     593       
  Partial          0       0       
  Missed           0       0       

Review entire Coverage Diff as of 78dc9c1

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[Callek]

See-Also, Mozilla Bug 1192021 (comment # 11)

[hynek]

Nice edge case, thanks!

I can't release it before next week tho because I'm on a vacation and I don't have my notebook on me.

You can use the time to add yourself to authors. :)

[hynek]

Oh and please add a test case for your exact use case, thanks!

[Callek]

How's that?

[Callek]

casual nudge. :-)

[hynek]

Sorry, first weeks are crazy. :)

[hynek]

Oops can you rebase/merge forward please?

[Callek]

The conflict is from your py3.5 release notes change... but sure...

[Callek]

...merged in master

[hynek]

FYI, 15.3.0 with this change is out. Thank you for your contribution: https://pypi.python.org/pypi/structlog/15.3.0