(bug 18834) Add an edit count to rollback link

Add an edit count to rollback link to show how many edits will be
rollbacked. When the count is over 10 the text "more than 10 edits" will
be outputed.

Change-Id: I5c4050e0a9197d4c505e85685a9780c97138d427

includes/DefaultSettings.php

@@ -2685,6 +2685,14 @@ $wgBetterDirectionality = true;
  */
 $wgSend404Code = true;
 
+
+/**
+ * The $wgShowRollbackEditCount variable is used to show how many edits will be
+ * rollback. The numeric value of the varible are the limit up to are counted.
+ * If the value is false or 0, the edits are not counted.
+ */
+$wgShowRollbackEditCount = 10;
+
 /** @} */ # End of output format settings }
 
 /*************************************************************************//**

includes/Linker.php

@@ -1673,6 +1673,8 @@ class Linker {
 	 * @return String: HTML fragment
 	 */
 	public static function buildRollbackLink( $rev, IContextSource $context = null ) {
+		global $wgShowRollbackEditCount;
+
 		if ( $context === null ) {
 			$context = RequestContext::getMain();
 		}
@@ -1687,13 +1689,50 @@ class Linker {
 			$query['bot'] = '1';
 			$query['hidediff'] = '1'; // bug 15999
 		}
-		return self::link(
-			$title,
-			$context->msg( 'rollbacklink' )->escaped(),
-			array( 'title' => $context->msg( 'tooltip-rollback' )->text() ),
-			$query,
-			array( 'known', 'noclasses' )
-		);
+
+		if( is_int( $wgShowRollbackEditCount ) && $wgShowRollbackEditCount > 0 ) {
+			$dbr = wfGetDB( DB_SLAVE );
+
+			// Up to the value of $wgShowRollbackEditCount revisions are counted
+			$res = $dbr->select( 'revision',
+				array( 'rev_id', 'rev_user_text' ),
+				array( 'rev_page' => $rev->getPage() ),
+				__METHOD__,
+				array(  'USE INDEX' => 'page_timestamp',
+					'ORDER BY' => 'rev_timestamp DESC',
+					'LIMIT' => $wgShowRollbackEditCount + 1 )
+			);
+
+			$editCount = 0;
+			while( $row = $dbr->fetchObject( $res ) ) {
+				if( $rev->getUserText() != $row->rev_user_text ) {
+					break;
+				}
+				$editCount++;
+			}
+
+			if( $editCount > $wgShowRollbackEditCount ) {
+				$editCount_output = $context->msg( 'rollbacklinkcount-morethan' )->numParams( $wgShowRollbackEditCount )->parse();
+			} else {
+				$editCount_output = $context->msg( 'rollbacklinkcount' )->numParams( $editCount )->parse();
+			}
+
+			return self::link(
+				$title,
+				$editCount_output,
+				array( 'title' => $context->msg( 'tooltip-rollback' )->text() ),
+				$query,
+				array( 'known', 'noclasses' )
+			);
+		} else {
+			return self::link(
+				$title,
+				$context->msg( 'rollbacklink' )->escaped(),
+				array( 'title' => $context->msg( 'tooltip-rollback' )->text() ),
+				$query,
+				array( 'known', 'noclasses' )
+			);
+		}
 	}
 
 	/**

languages/messages/MessagesEn.php

@@ -2927,6 +2927,8 @@ proceed with caution.',
 'rollback'          => 'Roll back edits',
 'rollback_short'    => 'Rollback',
 'rollbacklink'      => 'rollback',
+'rollbacklinkcount' => 'rollback $1 {{PLURAL:$1|edit|edits}}',
+'rollbacklinkcount-morethan' => 'rollback more than $1 {{PLURAL:$1|edit|edits}}',
 'rollbackfailed'    => 'Rollback failed',
 'cantrollback'      => 'Cannot revert edit;
 last contributor is only author of this page.',

languages/messages/MessagesQqq.php

@@ -2693,6 +2693,9 @@ $1 is the <b>approximate</b> number of revisions that the page has, the message
 'rollback_short' => '{{Identical|Rollback}}',
 'rollbacklink' => '{{Identical|Rollback}}
 This message has a tooltip {{msg-mw|tooltip-rollback}}',
+'rollbacklinkcount' => '* $1: the number of edit that will be rollbacked
+If $1 is over the value of $wgShowRollbackEditCount (default: 10) [[MediaWiki:Rollbacklinkcount-morethan/en|rollbacklinkcount-morethan]] is used',
+'rollbacklinkcount-morethan' => 'Similar to [[MediaWiki:Rollbacklinkcount/en|rollbacklinkcount]] but with prefix more than',
 'rollbackfailed' => '{{Identical|Rollback}}',
 'cantrollback' => '{{Identical|Revert}}
 {{Identical|Rollback}}',

maintenance/language/messages.inc

@@ -1962,6 +1962,8 @@ $wgMessageStructure = array(
 		'rollback',
 		'rollback_short',
 		'rollbacklink',
+		'rollbacklinkcount',
+		'rollbacklinkcount-morethan',
 		'rollbackfailed',
 		'cantrollback',
 		'alreadyrolled',