I recently added the UserMerge extension to my mediawiki installation. Followed the instructions found here. I enabled $wgShowExceptionDetails = true; and it gave me this:
[f9bbe088] /wiki/index.php/Special:UserMerge Exception from line 376 of /wiki/includes/SpecialPage.php: Call to undefined method UserMerge::getPageTitle
Backtrace:
#0 /wiki/extensions/UserMerge/UserMerge_body.php(128): SpecialPage->__call(string, array)
#1 /wiki/extensions/UserMerge/UserMerge_body.php(128): UserMerge->getPageTitle()
#2 /wiki/includes/SpecialPage.php(631): UserMerge->execute(NULL)
#3 /wiki/includes/SpecialPageFactory.php(488): SpecialPage->run(NULL)
#4 /wiki/includes/Wiki.php(298): SpecialPageFactory::executePath(Title, RequestContext)
#5 /wiki/includes/Wiki.php(602): MediaWiki->performRequest()
#6 /wiki/includes/Wiki.php(467): MediaWiki->main()
#7 /wiki/index.php(49): MediaWiki->run()
#8 {main}
Any ideas on a fix?
You've downloaded too new of a version of the extension. It looks like you may have grabbed the newest version of the code from the git master rather than downloading the appropriate snapshot version of the extension.
The version of the extension you have makes a call to $this->getPageTitle() in UserMerge_body.php. The getPageTitle function does not even exist (in SpecialPage.php) until Mediawiki version 1.23 (which is not yet released).
来源：https://stackoverflow.com/questions/20976472/usermerge-error