+ private function showMissingRevision() {
+ $out = $this->getOutput();
+
+ $missing = array();
+ if ( $this->mOldRev === null ) {
+ $missing[] = $this->deletedIdMarker( $this->mOldid );
+ }
+ if ( $this->mNewRev === null ) {
+ $missing[] = $this->deletedIdMarker( $this->mNewid );
+ }
+
+ $out->setPageTitle( $this->msg( 'errorpagetitle' ) );
+ $out->addWikiMsg( 'difference-missing-revision',
+ $this->getLanguage()->listToText( $missing ), count( $missing ) );
+ }
+