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diff --git a/www/wiki/includes/search/SearchExactMatchRescorer.php b/www/wiki/includes/search/SearchExactMatchRescorer.php
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+++ b/www/wiki/includes/search/SearchExactMatchRescorer.php
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+<?php
+/**
+ * Rescores results from a prefix search/opensearch to make sure the
+ * exact match is the first result.
+ *
+ * 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
+ */
+
+/**
+ * An utility class to rescore search results by looking for an exact match
+ * in the db and add the page found to the first position.
+ *
+ * NOTE: extracted from TitlePrefixSearch
+ * @ingroup Search
+ */
+class SearchExactMatchRescorer {
+	/**
+	 * Default search backend does proper prefix searching, but custom backends
+	 * may sort based on other algorithms that may cause the exact title match
+	 * to not be in the results or be lower down the list.
+	 * @param string $search the query
+	 * @param int[] $namespaces
+	 * @param string[] $srchres results
+	 * @param int $limit the max number of results to return
+	 * @return string[] munged results
+	 */
+	public function rescore( $search, $namespaces, $srchres, $limit ) {
+		// Pick namespace (based on PrefixSearch::defaultSearchBackend)
+		$ns = in_array( NS_MAIN, $namespaces ) ? NS_MAIN : reset( $namespaces );
+		$t = Title::newFromText( $search, $ns );
+		if ( !$t || !$t->exists() ) {
+			// No exact match so just return the search results
+			return $srchres;
+		}
+		$string = $t->getPrefixedText();
+		$key = array_search( $string, $srchres );
+		if ( $key !== false ) {
+			// Exact match was in the results so just move it to the front
+			return $this->pullFront( $key, $srchres );
+		}
+		// Exact match not in the search results so check for some redirect handling cases
+		if ( $t->isRedirect() ) {
+			$target = $this->getRedirectTarget( $t );
+			$key = array_search( $target, $srchres );
+			if ( $key !== false ) {
+				// Exact match is a redirect to one of the returned matches so pull the
+				// returned match to the front.  This might look odd but the alternative
+				// is to put the redirect in front and drop the match.  The name of the
+				// found match is often more descriptive/better formed than the name of
+				// the redirect AND by definition they share a prefix.  Hopefully this
+				// choice is less confusing and more helpful.  But it might not be.  But
+				// it is the choice we're going with for now.
+				return $this->pullFront( $key, $srchres );
+			}
+			$redirectTargetsToRedirect = $this->redirectTargetsToRedirect( $srchres );
+			if ( isset( $redirectTargetsToRedirect[$target] ) ) {
+				// The exact match and something in the results list are both redirects
+				// to the same thing!  In this case we'll pull the returned match to the
+				// top following the same logic above.  Again, it might not be a perfect
+				// choice but it'll do.
+				return $this->pullFront( $redirectTargetsToRedirect[$target], $srchres );
+			}
+		} else {
+			$redirectTargetsToRedirect = $this->redirectTargetsToRedirect( $srchres );
+			if ( isset( $redirectTargetsToRedirect[$string] ) ) {
+				// The exact match is the target of a redirect already in the results list so remove
+				// the redirect from the results list and push the exact match to the front
+				array_splice( $srchres, $redirectTargetsToRedirect[$string], 1 );
+				array_unshift( $srchres, $string );
+				return $srchres;
+			}
+		}
+
+		// Exact match is totally unique from the other results so just add it to the front
+		array_unshift( $srchres, $string );
+		// And roll one off the end if the results are too long
+		if ( count( $srchres ) > $limit ) {
+			array_pop( $srchres );
+		}
+		return $srchres;
+	}
+
+	/**
+	 * @param string[] $titles
+	 * @return array redirect target prefixedText to index of title in titles
+	 *   that is a redirect to it.
+	 */
+	private function redirectTargetsToRedirect( array $titles ) {
+		$result = [];
+		foreach ( $titles as $key => $titleText ) {
+			$title = Title::newFromText( $titleText );
+			if ( !$title || !$title->isRedirect() ) {
+				continue;
+			}
+			$target = $this->getRedirectTarget( $title );
+			if ( !$target ) {
+				continue;
+			}
+			$result[$target] = $key;
+		}
+		return $result;
+	}
+
+	/**
+	 * Returns an array where the element of $array at index $key becomes
+	 * the first element.
+	 * @param int $key key to pull to the front
+	 * @return array $array with the item at $key pulled to the front
+	 */
+	private function pullFront( $key, array $array ) {
+		$cut = array_splice( $array, $key, 1 );
+		array_unshift( $array, $cut[0] );
+		return $array;
+	}
+
+	/**
+	 * Get a redirect's destination from a title
+	 * @param Title $title A title to redirect. It may not redirect or even exist
+	 * @return null|string If title exists and redirects, get the destination's prefixed name
+	 */
+	private function getRedirectTarget( $title ) {
+		$page = WikiPage::factory( $title );
+		if ( !$page->exists() ) {
+			return null;
+		}
+		$redir = $page->getRedirectTarget();
+		return $redir ? $redir->getPrefixedText() : null;
+	}
+}