From 050a29d575b6f809d0cd46be2b91d3d54a70e08d Mon Sep 17 00:00:00 2001
From: Brion Vibber <brion@users.mediawiki.org>
Date: Thu, 4 Oct 2007 18:59:50 +0000
Subject: [PATCH] * (bug 11560) Fix broken HTML output from weird link nesting
 in edit comments.   Nested links (as in image caption text) still don't work
 _right_ but they're   less wrong.

Linker::formatComment() used a multi-pass run without proper protections,
making it possible for a later 'link' to erase a previous pass's start
or end tag. Switched to a single-pass run with preg_replace_callback which
avoids this.
---
 RELEASE-NOTES       |  3 +++
 includes/Linker.php | 55 +++++++++++++++++++++++++--------------------
 2 files changed, 34 insertions(+), 24 deletions(-)

diff --git a/RELEASE-NOTES b/RELEASE-NOTES
index 495aa4d8b1..6d395da19c 100644
--- a/RELEASE-NOTES
+++ b/RELEASE-NOTES
@@ -84,6 +84,9 @@ it from source control: http://www.mediawiki.org/wiki/Download_from_SVN
 * (bug 11478) Fix undefined method call in file deletion interface
 * (bug 278) Search results no longer highlight incorrect partial word matches
 * Compatibility with incorrectly detected old-style DJVU mime types
+* (bug 11560) Fix broken HTML output from weird link nesting in edit comments.
+  Nested links (as in image caption text) still don't work _right_ but they're
+  less wrong.
 
 
 === API changes in 1.12 ===
diff --git a/includes/Linker.php b/includes/Linker.php
index 1d187b8ca9..e61578d51c 100644
--- a/includes/Linker.php
+++ b/includes/Linker.php
@@ -988,42 +988,49 @@ class Linker {
 	 * Formats wiki links and media links in text; all other wiki formatting
 	 * is ignored
 	 *
+	 * @fixme doesn't handle sub-links as in image thumb texts like the main parser
 	 * @param string $comment Text to format links in
 	 * @return string
 	 */
 	public function formatLinksInComment( $comment ) {
+		return preg_replace_callback(
+			'/\[\[:?(.*?)(\|(.*?))*\]\]([^[]*)/',
+			array( $this, 'formatLinksInCommentCallback' ),
+			$comment );
+	}
+	
+	protected function formatLinksInCommentCallback( $match ) {
 		global $wgContLang;
 
 		$medians = '(?:' . preg_quote( Namespace::getCanonicalName( NS_MEDIA ), '/' ) . '|';
 		$medians .= preg_quote( $wgContLang->getNsText( NS_MEDIA ), '/' ) . '):';
+		
+		$comment = $match[0];
 
-		$match = array();
-		while(preg_match('/\[\[:?(.*?)(\|(.*?))*\]\](.*)$/',$comment,$match)) {
-			# Handle link renaming [[foo|text]] will show link as "text"
-			if( "" != $match[3] ) {
-				$text = $match[3];
-			} else {
-				$text = $match[1];
-			}
-			$submatch = array();
-			if( preg_match( '/^' . $medians . '(.*)$/i', $match[1], $submatch ) ) {
-				# Media link; trail not supported.
-				$linkRegexp = '/\[\[(.*?)\]\]/';
-				$thelink = $this->makeMediaLink( $submatch[1], "", $text );
+		# Handle link renaming [[foo|text]] will show link as "text"
+		if( "" != $match[3] ) {
+			$text = $match[3];
+		} else {
+			$text = $match[1];
+		}
+		$submatch = array();
+		if( preg_match( '/^' . $medians . '(.*)$/i', $match[1], $submatch ) ) {
+			# Media link; trail not supported.
+			$linkRegexp = '/\[\[(.*?)\]\]/';
+			$thelink = $this->makeMediaLink( $submatch[1], "", $text );
+		} else {
+			# Other kind of link
+			if( preg_match( $wgContLang->linkTrail(), $match[4], $submatch ) ) {
+				$trail = $submatch[1];
 			} else {
-				# Other kind of link
-				if( preg_match( $wgContLang->linkTrail(), $match[4], $submatch ) ) {
-					$trail = $submatch[1];
-				} else {
-					$trail = "";
-				}
-				$linkRegexp = '/\[\[(.*?)\]\]' . preg_quote( $trail, '/' ) . '/';
-				if (isset($match[1][0]) && $match[1][0] == ':')
-					$match[1] = substr($match[1], 1);
-				$thelink = $this->makeLink( $match[1], $text, "", $trail );
+				$trail = "";
 			}
-			$comment = preg_replace( $linkRegexp, StringUtils::escapeRegexReplacement( $thelink ), $comment, 1 );
+			$linkRegexp = '/\[\[(.*?)\]\]' . preg_quote( $trail, '/' ) . '/';
+			if (isset($match[1][0]) && $match[1][0] == ':')
+				$match[1] = substr($match[1], 1);
+			$thelink = $this->makeLink( $match[1], $text, "", $trail );
 		}
+		$comment = preg_replace( $linkRegexp, StringUtils::escapeRegexReplacement( $thelink ), $comment, 1 );
 
 		return $comment;
 	}
-- 
2.20.1