Wikimedia Bugzilla is closed!

Originally from: http://sourceforge.net/p/pywikipediabot/bugs/1201/
Reported by: dnessett
Created on: 2010-06-24 16:31:01
Subject: redirectRegex throws type error
Assigned to: xqt
Original description:
Running MW 1.13.2, the following command throws a type error:

$ python add\_text.py -cat:Pages\_with\_too\_many\_expensive\_parser\_function\_calls -text:" " -summary:"Test edit:Category jog for \[\[:Category:Pages with too many expensive parser function calls|Pages with too many expensive parser function calls\]\]"

The result is:

Getting \[\[Category:Pages with too many expensive parser function calls\]\]...
Loading 2009 White House Forum on Health Reform/Related Articles...
Do you want to accept these changes? \(\[y\]es, \[N\]o, \[a\]ll\) a
Updating page \[\[2009 White House Forum on Health Reform/Related Articles\]\] via API
Loading 2010 United Kingdom general election/Related Articles...
Traceback \(most recent call last\):
File "add\_text.py", line 417, in <module>
main\(\)
File "add\_text.py", line 413, in main
create=talkPage\)
File "add\_text.py", line 201, in add\_text
text = page.get\(\)
File "/usr/local/src/python/pywikipedia/local\_sites/wikipedia.py", line 619, in get
self.\_contents = self.\_getEditPage\(get\_redirect = get\_redirect, throttle = throttle, sysop = sysop\)
File "/usr/local/src/python/pywikipedia/local\_sites/wikipedia.py", line 727, in \_getEditPage
m = self.site\(\).redirectRegex\(\).match\(pagetext\)
File "/usr/local/src/python/pywikipedia/local\_sites/wikipedia.py", line 6644, in redirectRegex
pattern = r'\(?:' + '|'.join\(keywords\) + '\)'
TypeError

version.py output is:

$ python version.py
Pywikipedia \[http\] trunk/pywikipedia \(r8311, 2010/06/22, 13:20:10\)
Python 2.5.2 \(r252:60911, Jan 20 2010, 21:48:48\) 
\[GCC 4.2.4 \(Ubuntu 4.2.4-1ubuntu3\)\]
config-settings:
use\_api = True
use\_api\_login = True

This error occurs due to the following bug in the code. At line 6642 is the following code fragment:

try:
keywords = self.getmagicwords\('redirect'\)
pattern = r'\(?:' + '|'.join\(keywords\) + '\)'
except KeyError:
\# no localized keyword for redirects
pattern = r'\#%s' % default

getmagicwords is a one line method that simply calls siteinfo \(line 5480\) with the key 'magicwords'. At line 5518, siteinfo calls getData to obtain site data. When looking for magicwords, the method executes "for entry in data\[key\]" at line 5527. For certain versions of MW, magicwords are not returned as part of the site data and therefore data\[key\] returns a null result. Eventually, this leads to the KeyError exception at line 5538.

The bug arises because siteinfo catches the KeyError exception and returns a result of "None". When the call is unwound back to line 6643 the provision for a KeyError at line 6645 is vacuous. The KeyError has already been caught by siteinfo.

Consequently, the statement at line 6644 executes. This causes a TypeError since the keyword arguement to .join\(\) is null.