From c42684cca9d9035c444312fef220826fa48fc1d7 Mon Sep 17 00:00:00 2001
From: umherirrender <umherirrender_de.wp@web.de>
Date: Fri, 6 Dec 2013 18:12:24 +0100
Subject: [PATCH] Make a single colon an invalid title in php and js

When secureAndSplit gets a single colon as input, the leading colon
is stripped and produces a title with a empty string. This change makes
that impossible by moving the empty string check to after the substring
removal of the colon.

Bug: 54044
Change-Id: I574168c9ed281c535901c36dea7c179a4e794d20
---
 includes/Title.php                                     | 10 +++++-----
 resources/mediawiki/mediawiki.Title.js                 | 10 +++++-----
 tests/phpunit/includes/TitleTest.php                   |  1 +
 .../suites/resources/mediawiki/mediawiki.Title.test.js |  1 +
 4 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/includes/Title.php b/includes/Title.php
index 820842f5b9..a949ac301b 100644
--- a/includes/Title.php
+++ b/includes/Title.php
@@ -3163,10 +3163,6 @@ class Title {
 		$dbkey = preg_replace( '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u', '_', $dbkey );
 		$dbkey = trim( $dbkey, '_' );
 
-		if ( $dbkey == '' ) {
-			return false;
-		}
-
 		if ( strpos( $dbkey, UTF8_REPLACEMENT ) !== false ) {
 			# Contained illegal UTF-8 sequences or forbidden Unicode chars.
 			return false;
@@ -3176,12 +3172,16 @@ class Title {
 
 		# Initial colon indicates main namespace rather than specified default
 		# but should not create invalid {ns,title} pairs such as {0,Project:Foo}
-		if ( ':' == $dbkey[0] ) {
+		if ( $dbkey !== '' && ':' == $dbkey[0] ) {
 			$this->mNamespace = NS_MAIN;
 			$dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
 			$dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
 		}
 
+		if ( $dbkey == '' ) {
+			return false;
+		}
+
 		# Namespace or interwiki prefix
 		$firstPass = true;
 		$prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
diff --git a/resources/mediawiki/mediawiki.Title.js b/resources/mediawiki/mediawiki.Title.js
index de2d0130da..51770fd6d8 100644
--- a/resources/mediawiki/mediawiki.Title.js
+++ b/resources/mediawiki/mediawiki.Title.js
@@ -126,12 +126,8 @@
 			// Trim underscores
 			.replace( rUnderscoreTrim, '' );
 
-		if ( title === '' ) {
-			return false;
-		}
-
 		// Process initial colon
-		if ( title.charAt( 0 ) === ':' ) {
+		if ( title !== '' && title.charAt( 0 ) === ':' ) {
 			// Initial colon means main namespace instead of specified default
 			namespace = NS_MAIN;
 			title = title
@@ -141,6 +137,10 @@
 				.replace( rUnderscoreTrim, '' );
 		}
 
+		if ( title === '' ) {
+			return false;
+		}
+
 		// Process namespace prefix (if any)
 		m = title.match( rSplit );
 		if ( m ) {
diff --git a/tests/phpunit/includes/TitleTest.php b/tests/phpunit/includes/TitleTest.php
index 6bfe545301..58f01460a7 100644
--- a/tests/phpunit/includes/TitleTest.php
+++ b/tests/phpunit/includes/TitleTest.php
@@ -66,6 +66,7 @@ class TitleTest extends MediaWikiTestCase {
 		// Invalid
 		foreach ( array(
 			'',
+			':',
 			'__  __',
 			'  __  ',
 			// Bad characters forbidden regardless of wgLegalTitleChars
diff --git a/tests/qunit/suites/resources/mediawiki/mediawiki.Title.test.js b/tests/qunit/suites/resources/mediawiki/mediawiki.Title.test.js
index cb0bf6936c..4083564e88 100644
--- a/tests/qunit/suites/resources/mediawiki/mediawiki.Title.test.js
+++ b/tests/qunit/suites/resources/mediawiki/mediawiki.Title.test.js
@@ -80,6 +80,7 @@
 		],
 		invalid: [
 			'',
+			':',
 			'__  __',
 			'  __  ',
 			// Bad characters forbidden regardless of wgLegalTitleChars
-- 
2.20.1