Last modified: 2013-06-18 15:50:59 UTC
In Wikimedia Commons, when you type a single "0" (zero) in the search field, you are shown 2 page titles. There are indeed only two pages, the titles of which begin with "0", see here: http://commons.wikimedia.org/wiki/Special:AllPages/0 In the German language Wikipedia, when you do the same, nothing is shown. Yet, when you append a "'" (single quote) a single page title is shown, which is correct. There are several dozens of pages beginning with "0" in the German language Wikipedia, see here: http://de.wikipedia.org/wiki/Spezial:Alle_Seiten/0 So, I would expect the initial few be diplayed, when you type the initial "0". Maybe the different behavior of the two wikis is owed to the fact that, the German language Wikipedia has a page title "0", but I could not verify that.
It looks like it should work; I can pull a search: http://de.wikipedia.org/w/api.php?action=opensearch&format=jsonfm&search=0 I see some funky JS errors in firebug when trying to pull the '0' like: box.getNotificationWithValue is not a function http://de.wikipedia.org/skins-1.5/common/mwsuggest.js?195xx Line 125 os_decodeValue("0,5%-Hürde")mwsugges....js?195xx (line 125) os_createResultTable(Object searchform=searchform searchbox=searchInput, ["0", "0 v. Chr.", "0'00''", 7 more... 0=0 1=0 v. Chr. 2=0'00'' 3=0,5%-Hürde 4=0,5-%-Hürde])mwsugges....js?195xx (line 368) os_updateResults(Object searchform=searchform searchbox=searchInput, "0", "["0",["0","0 v. Chr.","0'00''","0,5%-H\u00fcrde","0,5-%-H\u00fcrde","0-0","0-1-Gesetz","0-8-15","0-km-Stein","0. Dynastie"]]", "http://de.wikipedia.org/w/api.php?action=opensearch&search=0&namespace=0|4|11")mwsugges....js?195xx (line 344) os_updateIfRelevant(Object searchform=searchform searchbox=searchInput, "0", "["0",["0","0 v. Chr.","0'00''","0,5%-H\u00fcrde","0,5-%-H\u00fcrde","0-0","0-1-Gesetz","0-8-15","0-km-Stein","0. Dynastie"]]", "http://de.wikipedia.org/w/api.php?action=opensearch&search=0&namespace=0|4|11")mwsugges....js?195xx (line 401) onreadystatechange()()mwsugges....js?195xx (line 428) [Break on this error] return decodeURIComponent(value); It's a little hard to follow, but I think the suggestion table generator is trying to URL-decode the results, which don't appear to be URL-encoded. When it hits the % sign in "0,5-%-Hürde" the URL decoding fails? And then firebug also spits out a totally unrelated error about a null or something. o_O
The search appears to be good, indeed. That looks like either debugging the JS-stuff, or simply coding the % as \0025 so as to avoid the "stupid" urldecoding attempt.
Marking as worksforme. Search front-end has changed a lot in two years, if the bug is stil there (I dont see it on de.wikipedia, '0' returns a few page names correctly), please re-open.