MediaWiki CentralAuth code

    /**
     * @param $row
     * @return bool|string
     */
    protected function getUserGroups( $row ) {
        if ( !$row->gug_numgroups ) {
            return false;
        }
        if ( $row->gug_numgroups == 1 ) {
            return User::makeGroupLinkWiki( $row->gug_singlegroup, User::getGroupMember( $row->gug_singlegroup ) );
        }

        $result = $this->mDb->select( 'global_user_groups', 'gug_group', array( 'gug_user' => $row->gu_id ), __METHOD__ );
        $globalgroups = array();
        foreach ( $result as $row2 ) {
            if ( !in_array( $row2->gug_group, array_keys( $this->wikiSets ) ) ) { // We don't need to get the sets of groups we already know about.
                $globalgroups[] = $row2->gug_group;
            }
        }

        if ( count ( $globalgroups ) != 0 ) {
            $wikiSetQuery = $this->mDb->select(
                array( 'global_group_restrictions', 'wikiset' ),
                array( 'ggr_group', 'ws_id', 'ws_name', 'ws_type', 'ws_wikis' ),
                array( 'ggr_set=ws_id', 'ggr_group IN (\'' . implode( "','", $globalgroups ) . '\')' ),
                __METHOD__
            );

            foreach ( $wikiSetQuery as $wikiSetRow ) {
                $this->wikiSets[$wikiSetRow->ggr_group] = WikiSet::newFromRow( $wikiSetRow );
            }
        }

        $rights = array();
        foreach ( $result as $row2 ) {
            if ( isset( $this->wikiSets[$row2->gug_group] ) && !$this->wikiSets[$row2->gug_group]->inSet() ) {
                $group = User::makeGroupLinkWiki( $row2->gug_group, User::getGroupMember( $row2->gug_group ) );
                $rights[] = Html::element( 'span', array( 'class' => 'groupnotappliedhere' ), $group );
            } else {
                $rights[] = User::makeGroupLinkWiki( $row2->gug_group, User::getGroupMember( $row2->gug_group ) );
            }
        }

        return implode( ', ', $rights );
    }