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diff --git a/www/wiki/includes/cache/LinkBatch.php b/www/wiki/includes/cache/LinkBatch.php
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+<?php
+/**
+ * Batch query to determine page existence.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Cache
+ */
+use MediaWiki\Linker\LinkTarget;
+use MediaWiki\MediaWikiServices;
+use Wikimedia\Rdbms\ResultWrapper;
+use Wikimedia\Rdbms\IDatabase;
+
+/**
+ * Class representing a list of titles
+ * The execute() method checks them all for existence and adds them to a LinkCache object
+ *
+ * @ingroup Cache
+ */
+class LinkBatch {
+	/**
+	 * 2-d array, first index namespace, second index dbkey, value arbitrary
+	 */
+	public $data = [];
+
+	/**
+	 * For debugging which method is using this class.
+	 */
+	protected $caller;
+
+	/**
+	 * @param Traversable|LinkTarget[] $arr Initial items to be added to the batch
+	 */
+	public function __construct( $arr = [] ) {
+		foreach ( $arr as $item ) {
+			$this->addObj( $item );
+		}
+	}
+
+	/**
+	 * Use ->setCaller( __METHOD__ ) to indicate which code is using this
+	 * class. Only used in debugging output.
+	 * @since 1.17
+	 *
+	 * @param string $caller
+	 */
+	public function setCaller( $caller ) {
+		$this->caller = $caller;
+	}
+
+	/**
+	 * @param LinkTarget $linkTarget
+	 */
+	public function addObj( $linkTarget ) {
+		if ( is_object( $linkTarget ) ) {
+			$this->add( $linkTarget->getNamespace(), $linkTarget->getDBkey() );
+		} else {
+			wfDebug( "Warning: LinkBatch::addObj got invalid LinkTarget object\n" );
+		}
+	}
+
+	/**
+	 * @param int $ns
+	 * @param string $dbkey
+	 */
+	public function add( $ns, $dbkey ) {
+		if ( $ns < 0 || $dbkey === '' ) {
+			return; // T137083
+		}
+		if ( !array_key_exists( $ns, $this->data ) ) {
+			$this->data[$ns] = [];
+		}
+
+		$this->data[$ns][strtr( $dbkey, ' ', '_' )] = 1;
+	}
+
+	/**
+	 * Set the link list to a given 2-d array
+	 * First key is the namespace, second is the DB key, value arbitrary
+	 *
+	 * @param array $array
+	 */
+	public function setArray( $array ) {
+		$this->data = $array;
+	}
+
+	/**
+	 * Returns true if no pages have been added, false otherwise.
+	 *
+	 * @return bool
+	 */
+	public function isEmpty() {
+		return $this->getSize() == 0;
+	}
+
+	/**
+	 * Returns the size of the batch.
+	 *
+	 * @return int
+	 */
+	public function getSize() {
+		return count( $this->data );
+	}
+
+	/**
+	 * Do the query and add the results to the LinkCache object
+	 *
+	 * @return array Mapping PDBK to ID
+	 */
+	public function execute() {
+		$linkCache = MediaWikiServices::getInstance()->getLinkCache();
+
+		return $this->executeInto( $linkCache );
+	}
+
+	/**
+	 * Do the query and add the results to a given LinkCache object
+	 * Return an array mapping PDBK to ID
+	 *
+	 * @param LinkCache &$cache
+	 * @return array Remaining IDs
+	 */
+	protected function executeInto( &$cache ) {
+		$res = $this->doQuery();
+		$this->doGenderQuery();
+		$ids = $this->addResultToCache( $cache, $res );
+
+		return $ids;
+	}
+
+	/**
+	 * Add a ResultWrapper containing IDs and titles to a LinkCache object.
+	 * As normal, titles will go into the static Title cache field.
+	 * This function *also* stores extra fields of the title used for link
+	 * parsing to avoid extra DB queries.
+	 *
+	 * @param LinkCache $cache
+	 * @param ResultWrapper $res
+	 * @return array Array of remaining titles
+	 */
+	public function addResultToCache( $cache, $res ) {
+		if ( !$res ) {
+			return [];
+		}
+
+		$titleFormatter = MediaWikiServices::getInstance()->getTitleFormatter();
+		// For each returned entry, add it to the list of good links, and remove it from $remaining
+
+		$ids = [];
+		$remaining = $this->data;
+		foreach ( $res as $row ) {
+			$title = new TitleValue( (int)$row->page_namespace, $row->page_title );
+			$cache->addGoodLinkObjFromRow( $title, $row );
+			$pdbk = $titleFormatter->getPrefixedDBkey( $title );
+			$ids[$pdbk] = $row->page_id;
+			unset( $remaining[$row->page_namespace][$row->page_title] );
+		}
+
+		// The remaining links in $data are bad links, register them as such
+		foreach ( $remaining as $ns => $dbkeys ) {
+			foreach ( $dbkeys as $dbkey => $unused ) {
+				$title = new TitleValue( (int)$ns, (string)$dbkey );
+				$cache->addBadLinkObj( $title );
+				$pdbk = $titleFormatter->getPrefixedDBkey( $title );
+				$ids[$pdbk] = 0;
+			}
+		}
+
+		return $ids;
+	}
+
+	/**
+	 * Perform the existence test query, return a ResultWrapper with page_id fields
+	 * @return bool|ResultWrapper
+	 */
+	public function doQuery() {
+		if ( $this->isEmpty() ) {
+			return false;
+		}
+
+		// This is similar to LinkHolderArray::replaceInternal
+		$dbr = wfGetDB( DB_REPLICA );
+		$table = 'page';
+		$fields = array_merge(
+			LinkCache::getSelectFields(),
+			[ 'page_namespace', 'page_title' ]
+		);
+
+		$conds = $this->constructSet( 'page', $dbr );
+
+		// Do query
+		$caller = __METHOD__;
+		if ( strval( $this->caller ) !== '' ) {
+			$caller .= " (for {$this->caller})";
+		}
+		$res = $dbr->select( $table, $fields, $conds, $caller );
+
+		return $res;
+	}
+
+	/**
+	 * Do (and cache) {{GENDER:...}} information for userpages in this LinkBatch
+	 *
+	 * @return bool Whether the query was successful
+	 */
+	public function doGenderQuery() {
+		if ( $this->isEmpty() ) {
+			return false;
+		}
+
+		global $wgContLang;
+		if ( !$wgContLang->needsGenderDistinction() ) {
+			return false;
+		}
+
+		$genderCache = MediaWikiServices::getInstance()->getGenderCache();
+		$genderCache->doLinkBatch( $this->data, $this->caller );
+
+		return true;
+	}
+
+	/**
+	 * Construct a WHERE clause which will match all the given titles.
+	 *
+	 * @param string $prefix The appropriate table's field name prefix ('page', 'pl', etc)
+	 * @param IDatabase $db DB object to use
+	 * @return string|bool String with SQL where clause fragment, or false if no items.
+	 */
+	public function constructSet( $prefix, $db ) {
+		return $db->makeWhereFrom2d( $this->data, "{$prefix}_namespace", "{$prefix}_title" );
+	}
+}