mizusumashi wrote:

Seaching for "special:" give same result as for "1". And results for "media:" and for "2" are same too.

aokomoriuta wrote:

No need redires=1, fulltext=Search, ns0=1 etc.

Just followings return returns same result.
http://en.wikipedia.org/w/index.php?title=Special:Search&search=special:
http://en.wikipedia.org/w/index.php?title=Special:Search&search=media:

aokomoriuta wrote:

Additionally:
This bug seems to come only on 1.17wmf1.

Following wikis which uses other version return different.

• The Documentation Foundation Wiki (1.16.0) http://wiki.documentfoundation.org/index.php?title=Special:Search&search=special:

• translatewiki.net (1.18alpha) http://translatewiki.net/w/i.php?title=Special:Search&search=special:

There are similar examples.

http://en.wikipedia.org/w/index.php?title=Special:Search&redirs=1&search=:&fulltext=Search&ns0=1

Wikimedia wikis are using Lucene Search. Looks like a problem with that search engine, not with the mediawiki search engine.

[Merging "MediaWiki extensions/Lucene Search" into "Wikimedia/lucene-search2", see bug 46542. You can filter bugmail for: search-component-merge-20130326 ]

Still weird in Cirrus. Will revisit.

Actually this is all working as intended, I see no bug here. Closing INVALID.