Merge "Add TitleExists hook"

diff --combined docs/hooks.txt
index d5fb2af,5be770e..f4b8ef2
--- 1/docs/hooks.txt
--- 2/docs/hooks.txt
+++ b/docs/hooks.txt
@@@ -1550,10 -1550,6 +1550,10 @@@ $title: The page's Title
    Currently unused, but planned to provide support for marking individual
    language links in the UI, e.g. for featured articles.
  
 +'LanguageSelector': Hook to change the language selector available on a page.
 +$out: The output page.
 +$cssClassName: CSS class name of the language selector.
 +
  'LinkBegin': Used when generating internal and interwiki links in
  Linker::link(), before processing starts.  Return false to skip default
  processing and return $ret. See documentation for Linker::link() for details on
@@@ -2594,6 -2590,10 +2594,10 @@@ database result
  &$titleArray: set this to an object to override the default object returned
  $res: database result used to create the object
  
+ 'TitleExists': Called when determining whether a page exists at a given title.
+ $title: The title being tested.
+ &$exists: Whether the title exists.
+ 
  'TitleQuickPermissions': Called from Title::checkQuickPermissions to add to
  or override the quick permissions check.
  $title: The Title object being accessed

diff --combined includes/Title.php
index 8727b74,8ffea35..74d78ba
--- 1/includes/Title.php
--- 2/includes/Title.php
+++ b/includes/Title.php
@@@ -3589,7 -3589,6 +3589,7 @@@ class Title 
         * Check whether a given move operation would be valid.
         * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
         *
 +       * @todo move this into MovePage
         * @param Title $nt The new title
         * @param bool $auth Indicates whether $wgUser's permissions
         *  should be checked
@@@ -3740,7 -3739,6 +3740,7 @@@
        /**
         * Move a title to a new location
         *
 +       * @todo Deprecate this in favor of MovePage
         * @param Title $nt The new title
         * @param bool $auth Indicates whether $wgUser's permissions
         *  should be checked
@@@ -3750,7 -3748,7 +3750,7 @@@
         * @return array|bool True on success, getUserPermissionsErrors()-like array on failure
         */
        public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
 -              global $wgUser, $wgCategoryCollation;
 +              global $wgUser;
                $err = $this->isValidMoveOperation( $nt, $auth, $reason );
                if ( is_array( $err ) ) {
                        // Auto-block user's IP if the account was "hard" blocked
@@@ -3764,13 -3762,290 +3764,13 @@@
  
                wfRunHooks( 'TitleMove', array( $this, $nt, $wgUser ) );
  
 -              // If it is a file, move it first.
 -              // It is done before all other moving stuff is done because it's hard to revert.
 -              $dbw = wfGetDB( DB_MASTER );
 -              if ( $this->getNamespace() == NS_FILE ) {
 -                      $file = wfLocalFile( $this );
 -                      if ( $file->exists() ) {
 -                              $status = $file->move( $nt );
 -                              if ( !$status->isOk() ) {
 -                                      return $status->getErrorsArray();
 -                              }
 -                      }
 -                      // Clear RepoGroup process cache
 -                      RepoGroup::singleton()->clearCache( $this );
 -                      RepoGroup::singleton()->clearCache( $nt ); # clear false negative cache
 -              }
 -
 -              $dbw->begin( __METHOD__ ); # If $file was a LocalFile, its transaction would have closed our own.
 -              $pageid = $this->getArticleID( self::GAID_FOR_UPDATE );
 -              $protected = $this->isProtected();
 -
 -              // Do the actual move
 -              $this->moveToInternal( $nt, $reason, $createRedirect );
 -
 -              // Refresh the sortkey for this row.  Be careful to avoid resetting
 -              // cl_timestamp, which may disturb time-based lists on some sites.
 -              // @todo This block should be killed, it's duplicating code
 -              // from LinksUpdate::getCategoryInsertions() and friends.
 -              $prefixes = $dbw->select(
 -                      'categorylinks',
 -                      array( 'cl_sortkey_prefix', 'cl_to' ),
 -                      array( 'cl_from' => $pageid ),
 -                      __METHOD__
 -              );
 -              if ( $nt->getNamespace() == NS_CATEGORY ) {
 -                      $type = 'subcat';
 -              } elseif ( $nt->getNamespace() == NS_FILE ) {
 -                      $type = 'file';
 -              } else {
 -                      $type = 'page';
 -              }
 -              foreach ( $prefixes as $prefixRow ) {
 -                      $prefix = $prefixRow->cl_sortkey_prefix;
 -                      $catTo = $prefixRow->cl_to;
 -                      $dbw->update( 'categorylinks',
 -                              array(
 -                                      'cl_sortkey' => Collation::singleton()->getSortKey(
 -                                              $nt->getCategorySortkey( $prefix ) ),
 -                                      'cl_collation' => $wgCategoryCollation,
 -                                      'cl_type' => $type,
 -                                      'cl_timestamp=cl_timestamp' ),
 -                              array(
 -                                      'cl_from' => $pageid,
 -                                      'cl_to' => $catTo ),
 -                              __METHOD__
 -                      );
 -              }
 -
 -              $redirid = $this->getArticleID();
 -
 -              if ( $protected ) {
 -                      # Protect the redirect title as the title used to be...
 -                      $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
 -                              array(
 -                                      'pr_page' => $redirid,
 -                                      'pr_type' => 'pr_type',
 -                                      'pr_level' => 'pr_level',
 -                                      'pr_cascade' => 'pr_cascade',
 -                                      'pr_user' => 'pr_user',
 -                                      'pr_expiry' => 'pr_expiry'
 -                              ),
 -                              array( 'pr_page' => $pageid ),
 -                              __METHOD__,
 -                              array( 'IGNORE' )
 -                      );
 -                      # Update the protection log
 -                      $log = new LogPage( 'protect' );
 -                      $comment = wfMessage(
 -                              'prot_1movedto2',
 -                              $this->getPrefixedText(),
 -                              $nt->getPrefixedText()
 -                      )->inContentLanguage()->text();
 -                      if ( $reason ) {
 -                              $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
 -                      }
 -                      // @todo FIXME: $params?
 -                      $logId = $log->addEntry(
 -                              'move_prot',
 -                              $nt,
 -                              $comment,
 -                              array( $this->getPrefixedText() ),
 -                              $wgUser
 -                      );
 -
 -                      // reread inserted pr_ids for log relation
 -                      $insertedPrIds = $dbw->select(
 -                              'page_restrictions',
 -                              'pr_id',
 -                              array( 'pr_page' => $redirid ),
 -                              __METHOD__
 -                      );
 -                      $logRelationsValues = array();
 -                      foreach ( $insertedPrIds as $prid ) {
 -                              $logRelationsValues[] = $prid->pr_id;
 -                      }
 -                      $log->addRelations( 'pr_id', $logRelationsValues, $logId );
 -              }
 -
 -              // Update *_from_namespace fields as needed
 -              if ( $this->getNamespace() != $nt->getNamespace() ) {
 -                      $dbw->update( 'pagelinks',
 -                              array( 'pl_from_namespace' => $nt->getNamespace() ),
 -                              array( 'pl_from' => $pageid ),
 -                              __METHOD__
 -                      );
 -                      $dbw->update( 'templatelinks',
 -                              array( 'tl_from_namespace' => $nt->getNamespace() ),
 -                              array( 'tl_from' => $pageid ),
 -                              __METHOD__
 -                      );
 -                      $dbw->update( 'imagelinks',
 -                              array( 'il_from_namespace' => $nt->getNamespace() ),
 -                              array( 'il_from' => $pageid ),
 -                              __METHOD__
 -                      );
 -              }
 -
 -              # Update watchlists
 -              $oldtitle = $this->getDBkey();
 -              $newtitle = $nt->getDBkey();
 -              $oldsnamespace = MWNamespace::getSubject( $this->getNamespace() );
 -              $newsnamespace = MWNamespace::getSubject( $nt->getNamespace() );
 -              if ( $oldsnamespace != $newsnamespace || $oldtitle != $newtitle ) {
 -                      WatchedItem::duplicateEntries( $this, $nt );
 -              }
 -
 -              $dbw->commit( __METHOD__ );
 -
 -              wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid, $reason ) );
 -              return true;
 -      }
 -
 -      /**
 -       * Move page to a title which is either a redirect to the
 -       * source page or nonexistent
 -       *
 -       * @param Title $nt The page to move to, which should be a redirect or nonexistent
 -       * @param string $reason The reason for the move
 -       * @param bool $createRedirect Whether to leave a redirect at the old title. Does not check
 -       *   if the user has the suppressredirect right
 -       * @throws MWException
 -       */
 -      private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
 -              global $wgUser, $wgContLang;
 -
 -              if ( $nt->exists() ) {
 -                      $moveOverRedirect = true;
 -                      $logType = 'move_redir';
 -              } else {
 -                      $moveOverRedirect = false;
 -                      $logType = 'move';
 -              }
 -
 -              if ( $createRedirect ) {
 -                      if ( $this->getNamespace() == NS_CATEGORY
 -                              && !wfMessage( 'category-move-redirect-override' )->inContentLanguage()->isDisabled()
 -                      ) {
 -                              $redirectContent = new WikitextContent(
 -                                      wfMessage( 'category-move-redirect-override' )
 -                                              ->params( $nt->getPrefixedText() )->inContentLanguage()->plain() );
 -                      } else {
 -                              $contentHandler = ContentHandler::getForTitle( $this );
 -                              $redirectContent = $contentHandler->makeRedirectContent( $nt,
 -                                      wfMessage( 'move-redirect-text' )->inContentLanguage()->plain() );
 -                      }
 -
 -                      // NOTE: If this page's content model does not support redirects, $redirectContent will be null.
 +              $mp = new MovePage( $this, $nt );
 +              $status = $mp->move( $wgUser, $reason, $createRedirect );
 +              if ( $status->isOK() ) {
 +                      return true;
                } else {
 -                      $redirectContent = null;
 -              }
 -
 -              // bug 57084: log_page should be the ID of the *moved* page
 -              $oldid = $this->getArticleID();
 -              $logTitle = clone $this;
 -
 -              $logEntry = new ManualLogEntry( 'move', $logType );
 -              $logEntry->setPerformer( $wgUser );
 -              $logEntry->setTarget( $logTitle );
 -              $logEntry->setComment( $reason );
 -              $logEntry->setParameters( array(
 -                      '4::target' => $nt->getPrefixedText(),
 -                      '5::noredir' => $redirectContent ? '0': '1',
 -              ) );
 -
 -              $formatter = LogFormatter::newFromEntry( $logEntry );
 -              $formatter->setContext( RequestContext::newExtraneousContext( $this ) );
 -              $comment = $formatter->getPlainActionText();
 -              if ( $reason ) {
 -                      $comment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
 -              }
 -              # Truncate for whole multibyte characters.
 -              $comment = $wgContLang->truncate( $comment, 255 );
 -
 -              $dbw = wfGetDB( DB_MASTER );
 -
 -              $newpage = WikiPage::factory( $nt );
 -
 -              if ( $moveOverRedirect ) {
 -                      $newid = $nt->getArticleID();
 -                      $newcontent = $newpage->getContent();
 -
 -                      # Delete the old redirect. We don't save it to history since
 -                      # by definition if we've got here it's rather uninteresting.
 -                      # We have to remove it so that the next step doesn't trigger
 -                      # a conflict on the unique namespace+title index...
 -                      $dbw->delete( 'page', array( 'page_id' => $newid ), __METHOD__ );
 -
 -                      $newpage->doDeleteUpdates( $newid, $newcontent );
 +                      return $status->getErrorsArray();
                }
 -
 -              # Save a null revision in the page's history notifying of the move
 -              $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true, $wgUser );
 -              if ( !is_object( $nullRevision ) ) {
 -                      throw new MWException( 'No valid null revision produced in ' . __METHOD__ );
 -              }
 -
 -              $nullRevision->insertOn( $dbw );
 -
 -              # Change the name of the target page:
 -              $dbw->update( 'page',
 -                      /* SET */ array(
 -                              'page_namespace' => $nt->getNamespace(),
 -                              'page_title' => $nt->getDBkey(),
 -                      ),
 -                      /* WHERE */ array( 'page_id' => $oldid ),
 -                      __METHOD__
 -              );
 -
 -              // clean up the old title before reset article id - bug 45348
 -              if ( !$redirectContent ) {
 -                      WikiPage::onArticleDelete( $this );
 -              }
 -
 -              $this->resetArticleID( 0 ); // 0 == non existing
 -              $nt->resetArticleID( $oldid );
 -              $newpage->loadPageData( WikiPage::READ_LOCKING ); // bug 46397
 -
 -              $newpage->updateRevisionOn( $dbw, $nullRevision );
 -
 -              wfRunHooks( 'NewRevisionFromEditComplete',
 -                      array( $newpage, $nullRevision, $nullRevision->getParentId(), $wgUser ) );
 -
 -              $newpage->doEditUpdates( $nullRevision, $wgUser, array( 'changed' => false ) );
 -
 -              if ( !$moveOverRedirect ) {
 -                      WikiPage::onArticleCreate( $nt );
 -              }
 -
 -              # Recreate the redirect, this time in the other direction.
 -              if ( $redirectContent ) {
 -                      $redirectArticle = WikiPage::factory( $this );
 -                      $redirectArticle->loadFromRow( false, WikiPage::READ_LOCKING ); // bug 46397
 -                      $newid = $redirectArticle->insertOn( $dbw );
 -                      if ( $newid ) { // sanity
 -                              $this->resetArticleID( $newid );
 -                              $redirectRevision = new Revision( array(
 -                                      'title' => $this, // for determining the default content model
 -                                      'page' => $newid,
 -                                      'user_text' => $wgUser->getName(),
 -                                      'user' => $wgUser->getId(),
 -                                      'comment' => $comment,
 -                                      'content' => $redirectContent ) );
 -                              $redirectRevision->insertOn( $dbw );
 -                              $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
 -
 -                              wfRunHooks( 'NewRevisionFromEditComplete',
 -                                      array( $redirectArticle, $redirectRevision, false, $wgUser ) );
 -
 -                              $redirectArticle->doEditUpdates( $redirectRevision, $wgUser, array( 'created' => true ) );
 -                      }
 -              }
 -
 -              # Log the move
 -              $logid = $logEntry->insert();
 -              $logEntry->publish( $logid );
        }
  
        /**
@@@ -4333,7 -4608,9 +4333,9 @@@
         * @return bool
         */
        public function exists() {
-               return $this->getArticleID() != 0;
+               $exists = $this->getArticleID() != 0;
+               wfRunHooks( 'TitleExists', array( $this, &$exists ) );
+               return $exists;
        }
  
        /**