Last modified: 2014-11-12 17:28:52 UTC
1. Create a page with "{{this is}}" 2. Edit the page and replace its content by "*THIS IS A BUG ON ABUSE FILTER!": https://pt.wikibooks.org/wiki/Project:Caixa_de_areia?diff=258499 3. Open [[Special:AbuseFilter/test]], which in my case was https://pt.wikibooks.org/wiki/Special:AbuseFilter/test?uselang=en 4. Type ------------------------------------------------------------------------ length(added_lines) <= 2 & contains_any( added_lines, "THIS IS A BUG" ) ------------------------------------------------------------------------ 5. Click "Test" and bang! The edit is detected! If it is of any help, here is the link provided to "examine" the edit: https://pt.wikibooks.org/w/index.php?title=Especial:Filtro_de_abusos/examine/262161&testfilter=length%28added_lines%29+%3D%3D+1+%26+contains_any%28+added_lines%2C+"THIS+IS+A+BUG"+%29%0A&uselang=en The filter shouldn't detect it, because "added_lines" obviously has a lot more than 2 characters. Nonetheless, if I replace "<= 2" by "== 1" it is still detected. How can a string of 31 characters have length 1? This is plain wrong...
Ok, so I made one more test at https://pt.wikibooks.org/w/index.php?title=Wikilivros%3ACaixa_de_areia&diff=258547&oldid=258546 and used Special:AbuseFilter/test to check the following filter: ------------------------------------------------------------------------ length(added_lines) == 3 & contains_any( added_lines, "Lorem" ) ------------------------------------------------------------------------ and the edit was detected. It seems abuse filter's "added_lines" is an array and then "length(added_lines)" is the number of items on this array. Such a behavior is not documented at https://www.mediawiki.org/wiki/Extension:AbuseFilter/Rules_format and it is not obvious from https://pt.wikibooks.org/w/index.php?title=Especial:Filtro_de_abusos/examine/262215&testfilter=length%28added_lines%29+%3D%3D+3+%26+contains_any%28+added_lines%2C+%22Lorem%22+%29%0A that the value of "added_lines" is an array (not an string).
A similar problem happens when I use "user_groups": For a user , The test -------------------------- "confirmed" in user_groups -------------------------- matches a user which is in the group "autoconfirmed" but **not** in the group "confirmed". But the documentation[1] says "in" applies only to "strings", so why when I execute -------------------------- length(user_groups)=4 -------------------------- I also get a match? (the user in question is in exactly 4 groups) If "user_groups" is a string, its length should be at least the length of "confirmed" (which is 9), not 4. [1] http://www.mediawiki.org/wiki/Extension:AbuseFilter/Rules_format#Keywords
Here is another test which returns 1 (which means "true"): (list:= ["a", "b", "c"];) & contains_any(list,"a\n") I think the real bug is we have no documentation about these variables being arrays and how they are converted to strings (notice the "\n" in the above example).
See also: * [[mw:Extension_talk:AbuseFilter/Rules_format#Please_add_description_of_variable_values]]
According to https://ru.wikipedia.org/wiki/Special:AbuseFilter/history/99/diff/prev/2152 the the variable "added_lines" was changed to an array somewhere from 13 February 2013 and as such "length (added_lines)" now gets the number of rows, and this changed the conditions under which existing filters were triggered.
Is this working like this since 2009??? I found the following on r49221: --------------------------------------------------------------------------- * Use lists instead of implode()d strings in built-in variables wherever it's possible ATTENTION! This may break filters that rely on "added_lines contains 'bla-bla'" syntax. They'll need to be replaced with "string(added_lines) contains 'bla-bla'" ---------------------------------------------------------------------------
No need for "[regression]" in subject if you also set the keyword. However, not sure if I would call it a regression if it's been like this for four years.
Another example of the confusion caused by this (from 17 June 2009): * [[Special:AbuseFilter/history/172/diff/prev/2121]] * [[Wikipedia talk:Edit filter/Archive 3#Filter stopped working - strange testing results ..]]
See also: https://www.mediawiki.org/wiki/Extension:AbuseFilter/Rules_format#Conditions (added and documented by Helder)
(In reply to comment #9) > See also: > https://www.mediawiki.org/wiki/Extension:AbuseFilter/Rules_format#Conditions > > (added and documented by Helder) Whoops, ignore that, wrong bug!
