Wikimedia Bugzilla is closed!

Created attachment 7585 [details]
Only check correctness of add object if remove object does not exist

in checkSubject(), the first line:
if ( !$add->equals($this->title) ) return false;
... creates errors when doing delete operations using the internal API.

This is apparently due to the fact that it is executed regardless of whether a remove object exists or not, while the correct behaviour would be to only execute it if a remove object does not exist (because when doing remove operations, you will not send a valid add object).

Solution: Move the line above into the "else" part of the if ( $remove->exists() ) just below it (see submitted patch).