I installed the 1.13.0rc1 code, and set Mediawiki up to use SQLite. When doing a search off the main page, I would always be presented with the following error:
Fatal error: Call to undefined method SearchEngineDummy::replacePrefixes() in F:\www\Program\www\localhost\wikidev\includes\specials\SpecialSearch.php on line 170
Looked at the SearchEngine class and the SearchEngineDummy class in the 'includes/SearchEngine.php' file.
Looked at the SearchEngineDummy class, confirmed that there was no 'replacePrefixes' function.
Looked at the SearchEngine class, confirmed that there was a 'replacePrefixes' function.
Added empty 'replacePrefixes' function to the SearchEngineDummy class.
Error went away.
I hope this helps, please feel free to ask for additional information if necessary.