update to MediaWiki 1.17.0

1 files changed, 740 insertions, 0 deletions

diff --git a/includes/resourceloader/ResourceLoader.php b/includes/resourceloader/ResourceLoader.php
new file mode 100644
index 00000000..c18022a4
--- /dev/null
+++ b/includes/resourceloader/ResourceLoader.php
@@ -0,0 +1,740 @@
+<?php
+/**
+ * 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
+ * @author Roan Kattouw
+ * @author Trevor Parscal
+ */
+
+/**
+ * Dynamic JavaScript and CSS resource loading system.
+ *
+ * Most of the documention is on the MediaWiki documentation wiki starting at:
+ *    http://www.mediawiki.org/wiki/ResourceLoader
+ */
+class ResourceLoader {
+
+	/* Protected Static Members */
+	protected static $filterCacheVersion = 2;
+
+	/** Array: List of module name/ResourceLoaderModule object pairs */
+	protected $modules = array();
+	/** Associative array mapping module name to info associative array */
+	protected $moduleInfos = array();
+
+	/* Protected Methods */
+
+	/**
+	 * Loads information stored in the database about modules.
+	 * 
+	 * This method grabs modules dependencies from the database and updates modules 
+	 * objects.
+	 * 
+	 * This is not inside the module code because it is much faster to 
+	 * request all of the information at once than it is to have each module 
+	 * requests its own information. This sacrifice of modularity yields a substantial
+	 * performance improvement.
+	 * 
+	 * @param $modules Array: List of module names to preload information for
+	 * @param $context ResourceLoaderContext: Context to load the information within
+	 */
+	public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
+		if ( !count( $modules ) ) {
+			return; // or else Database*::select() will explode, plus it's cheaper!
+		}
+		$dbr = wfGetDB( DB_SLAVE );
+		$skin = $context->getSkin();
+		$lang = $context->getLanguage();
+		
+		// Get file dependency information
+		$res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
+				'md_module' => $modules,
+				'md_skin' => $context->getSkin()
+			), __METHOD__
+		);
+
+		// Set modules' dependencies
+		$modulesWithDeps = array();
+		foreach ( $res as $row ) {
+			$this->getModule( $row->md_module )->setFileDependencies( $skin,
+				FormatJson::decode( $row->md_deps, true )
+			);
+			$modulesWithDeps[] = $row->md_module;
+		}
+
+		// Register the absence of a dependency row too
+		foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
+			$this->getModule( $name )->setFileDependencies( $skin, array() );
+		}
+		
+		// Get message blob mtimes. Only do this for modules with messages
+		$modulesWithMessages = array();
+		foreach ( $modules as $name ) {
+			if ( count( $this->getModule( $name )->getMessages() ) ) {
+				$modulesWithMessages[] = $name;
+			}
+		}
+		$modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
+		if ( count( $modulesWithMessages ) ) {
+			$res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
+					'mr_resource' => $modulesWithMessages,
+					'mr_lang' => $lang
+				), __METHOD__
+			);
+			foreach ( $res as $row ) {
+				$this->getModule( $row->mr_resource )->setMsgBlobMtime( $lang, $row->mr_timestamp );
+				unset( $modulesWithoutMessages[$row->mr_resource] );
+			}
+		} 
+		foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
+			$this->getModule( $name )->setMsgBlobMtime( $lang, 0 );
+		}
+	}
+
+	/**
+	 * Runs JavaScript or CSS data through a filter, caching the filtered result for future calls.
+	 * 
+	 * Available filters are:
+	 *  - minify-js \see JavaScriptMinifier::minify
+	 *  - minify-css \see CSSMin::minify
+	 * 
+	 * If $data is empty, only contains whitespace or the filter was unknown, 
+	 * $data is returned unmodified.
+	 * 
+	 * @param $filter String: Name of filter to run
+	 * @param $data String: Text to filter, such as JavaScript or CSS text
+	 * @return String: Filtered data, or a comment containing an error message
+	 */
+	protected function filter( $filter, $data ) {
+		global $wgResourceLoaderMinifierStatementsOnOwnLine, $wgResourceLoaderMinifierMaxLineLength;
+		wfProfileIn( __METHOD__ );
+
+		// For empty/whitespace-only data or for unknown filters, don't perform 
+		// any caching or processing
+		if ( trim( $data ) === '' 
+			|| !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) 
+		{
+			wfProfileOut( __METHOD__ );
+			return $data;
+		}
+
+		// Try for cache hit
+		// Use CACHE_ANYTHING since filtering is very slow compared to DB queries
+		$key = wfMemcKey( 'resourceloader', 'filter', $filter, md5( $data ) );
+		$cache = wfGetCache( CACHE_ANYTHING );
+		$cacheEntry = $cache->get( $key );
+		if ( is_string( $cacheEntry ) ) {
+			wfProfileOut( __METHOD__ );
+			return $cacheEntry;
+		}
+
+		// Run the filter - we've already verified one of these will work
+		try {
+			switch ( $filter ) {
+				case 'minify-js':
+					$result = JavaScriptMinifier::minify( $data,
+						$wgResourceLoaderMinifierStatementsOnOwnLine,
+						$wgResourceLoaderMinifierMaxLineLength
+					);
+					break;
+				case 'minify-css':
+					$result = CSSMin::minify( $data );
+					break;
+			}
+
+			// Save filtered text to Memcached
+			$cache->set( $key, $result );
+		} catch ( Exception $exception ) {
+			// Return exception as a comment
+			$result = "/*\n{$exception->__toString()}\n*/\n";
+		}
+
+		wfProfileOut( __METHOD__ );
+		
+		return $result;
+	}
+
+	/* Methods */
+
+	/**
+	 * Registers core modules and runs registration hooks.
+	 */
+	public function __construct() {
+		global $IP, $wgResourceModules;
+		
+		wfProfileIn( __METHOD__ );
+		
+		// Register core modules
+		$this->register( include( "$IP/resources/Resources.php" ) );
+		// Register extension modules
+		wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
+		$this->register( $wgResourceModules );
+		
+		wfProfileOut( __METHOD__ );
+	}
+
+	/**
+	 * Registers a module with the ResourceLoader system.
+	 * 
+	 * @param $name Mixed: Name of module as a string or List of name/object pairs as an array
+	 * @param $info Module info array. For backwards compatibility with 1.17alpha, 
+	 *   this may also be a ResourceLoaderModule object. Optional when using 
+	 *   multiple-registration calling style.
+	 * @throws MWException: If a duplicate module registration is attempted
+	 * @throws MWException: If a module name contains illegal characters (pipes or commas)
+	 * @throws MWException: If something other than a ResourceLoaderModule is being registered
+	 * @return Boolean: False if there were any errors, in which case one or more modules were not
+	 *     registered
+	 */
+	public function register( $name, $info = null ) {
+		wfProfileIn( __METHOD__ );
+
+		// Allow multiple modules to be registered in one call
+		if ( is_array( $name ) ) {
+			foreach ( $name as $key => $value ) {
+				$this->register( $key, $value );
+			}
+			wfProfileOut( __METHOD__ );
+			return;
+		}
+
+		// Disallow duplicate registrations
+		if ( isset( $this->moduleInfos[$name] ) ) {
+			// A module has already been registered by this name
+			throw new MWException(
+				'ResourceLoader duplicate registration error. ' . 
+				'Another module has already been registered as ' . $name
+			);
+		}
+		
+		// Check $name for illegal characters
+		if ( preg_match( '/[|,]/', $name ) ) {
+			throw new MWException( "ResourceLoader module name '$name' is invalid. Names may not contain pipes (|) or commas (,)" );
+		}
+
+		// Attach module
+		if ( is_object( $info ) ) {
+			// Old calling convention
+			// Validate the input
+			if ( !( $info instanceof ResourceLoaderModule ) ) {
+				throw new MWException( 'ResourceLoader invalid module error. ' . 
+					'Instances of ResourceLoaderModule expected.' );
+			}
+
+			$this->moduleInfos[$name] = array( 'object' => $info );
+			$info->setName( $name );
+			$this->modules[$name] = $info;
+		} else {
+			// New calling convention
+			$this->moduleInfos[$name] = $info;
+		}
+
+		wfProfileOut( __METHOD__ );
+	}
+
+ 	/**
+	 * Get a list of module names
+	 *
+	 * @return Array: List of module names
+	 */
+	public function getModuleNames() {
+		return array_keys( $this->moduleInfos );
+	}
+
+	/**
+	 * Get the ResourceLoaderModule object for a given module name.
+	 *
+	 * @param $name String: Module name
+	 * @return Mixed: ResourceLoaderModule if module has been registered, null otherwise
+	 */
+	public function getModule( $name ) {
+		if ( !isset( $this->modules[$name] ) ) {
+			if ( !isset( $this->moduleInfos[$name] ) ) {
+				// No such module
+				return null;
+			}
+			// Construct the requested object
+			$info = $this->moduleInfos[$name];
+			if ( isset( $info['object'] ) ) {
+				// Object given in info array
+				$object = $info['object'];
+			} else {
+				if ( !isset( $info['class'] ) ) {
+					$class = 'ResourceLoaderFileModule';
+				} else {
+					$class = $info['class'];
+				}
+				$object = new $class( $info );
+			}
+			$object->setName( $name );
+			$this->modules[$name] = $object;
+		}
+
+		return $this->modules[$name];
+	}
+
+	/**
+	 * Outputs a response to a resource load-request, including a content-type header.
+	 *
+	 * @param $context ResourceLoaderContext: Context in which a response should be formed
+	 */
+	public function respond( ResourceLoaderContext $context ) {
+		global $wgResourceLoaderMaxage, $wgCacheEpoch;
+		
+		// Buffer output to catch warnings. Normally we'd use ob_clean() on the
+		// top-level output buffer to clear warnings, but that breaks when ob_gzhandler
+		// is used: ob_clean() will clear the GZIP header in that case and it won't come
+		// back for subsequent output, resulting in invalid GZIP. So we have to wrap
+		// the whole thing in our own output buffer to be sure the active buffer
+		// doesn't use ob_gzhandler.
+		// See http://bugs.php.net/bug.php?id=36514
+		ob_start();
+
+		wfProfileIn( __METHOD__ );
+		$exceptions = '';
+
+		// Split requested modules into two groups, modules and missing
+		$modules = array();
+		$missing = array();
+		foreach ( $context->getModules() as $name ) {
+			if ( isset( $this->moduleInfos[$name] ) ) {
+				$modules[$name] = $this->getModule( $name );
+			} else {
+				$missing[] = $name;
+			}
+		}
+
+		// If a version wasn't specified we need a shorter expiry time for updates 
+		// to propagate to clients quickly
+		if ( is_null( $context->getVersion() ) ) {
+			$maxage  = $wgResourceLoaderMaxage['unversioned']['client'];
+			$smaxage = $wgResourceLoaderMaxage['unversioned']['server'];
+		}
+		// If a version was specified we can use a longer expiry time since changing 
+		// version numbers causes cache misses
+		else {
+			$maxage  = $wgResourceLoaderMaxage['versioned']['client'];
+			$smaxage = $wgResourceLoaderMaxage['versioned']['server'];
+		}
+
+		// Preload information needed to the mtime calculation below
+		try {
+			$this->preloadModuleInfo( array_keys( $modules ), $context );
+		} catch( Exception $e ) {
+			// Add exception to the output as a comment
+			$exceptions .= "/*\n{$e->__toString()}\n*/\n";
+		}
+
+		wfProfileIn( __METHOD__.'-getModifiedTime' );
+
+		$private = false;
+		// To send Last-Modified and support If-Modified-Since, we need to detect 
+		// the last modified time
+		$mtime = wfTimestamp( TS_UNIX, $wgCacheEpoch );
+		foreach ( $modules as $module ) {
+			try {
+				// Bypass Squid and other shared caches if the request includes any private modules
+				if ( $module->getGroup() === 'private' ) {
+					$private = true;
+				}
+				// Calculate maximum modified time
+				$mtime = max( $mtime, $module->getModifiedTime( $context ) );
+			} catch ( Exception $e ) {
+				// Add exception to the output as a comment
+				$exceptions .= "/*\n{$e->__toString()}\n*/\n";
+			}
+		}
+
+		wfProfileOut( __METHOD__.'-getModifiedTime' );
+
+		if ( $context->getOnly() === 'styles' ) {
+			header( 'Content-Type: text/css; charset=utf-8' );
+		} else {
+			header( 'Content-Type: text/javascript; charset=utf-8' );
+		}
+		header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
+		if ( $context->getDebug() ) {
+			// Do not cache debug responses
+			header( 'Cache-Control: private, no-cache, must-revalidate' );
+			header( 'Pragma: no-cache' );
+		} else {
+			if ( $private ) {
+				header( "Cache-Control: private, max-age=$maxage" );
+				$exp = $maxage;
+			} else {
+				header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
+				$exp = min( $maxage, $smaxage );
+			}
+			header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
+		}
+
+		// If there's an If-Modified-Since header, respond with a 304 appropriately
+		// Some clients send "timestamp;length=123". Strip the part after the first ';'
+		// so we get a valid timestamp.
+		$ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
+		if ( $ims !== false ) {
+			$imsTS = strtok( $ims, ';' );
+			if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
+				// There's another bug in ob_gzhandler (see also the comment at
+				// the top of this function) that causes it to gzip even empty
+				// responses, meaning it's impossible to produce a truly empty
+				// response (because the gzip header is always there). This is
+				// a problem because 304 responses have to be completely empty
+				// per the HTTP spec, and Firefox behaves buggily when they're not.
+				// See also http://bugs.php.net/bug.php?id=51579
+				// To work around this, we tear down all output buffering before
+				// sending the 304.
+				// On some setups, ob_get_level() doesn't seem to go down to zero
+				// no matter how often we call ob_get_clean(), so instead of doing
+				// the more intuitive while ( ob_get_level() > 0 ) ob_get_clean();
+				// we have to be safe here and avoid an infinite loop.
+				for ( $i = 0; $i < ob_get_level(); $i++ ) {
+					ob_end_clean();
+				}
+				
+				header( 'HTTP/1.0 304 Not Modified' );
+				header( 'Status: 304 Not Modified' );
+				wfProfileOut( __METHOD__ );
+				return;
+			}
+		}
+		
+		// Generate a response
+		$response = $this->makeModuleResponse( $context, $modules, $missing );
+		
+		// Prepend comments indicating exceptions
+		$response = $exceptions . $response;
+
+		// Capture any PHP warnings from the output buffer and append them to the
+		// response in a comment if we're in debug mode.
+		if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
+			$response = "/*\n$warnings\n*/\n" . $response;
+		}
+
+		// Remove the output buffer and output the response
+		ob_end_clean();
+		echo $response;
+
+		wfProfileOut( __METHOD__ );
+	}
+
+	/**
+	 * Generates code for a response
+	 * 
+	 * @param $context ResourceLoaderContext: Context in which to generate a response
+	 * @param $modules Array: List of module objects keyed by module name
+	 * @param $missing Array: List of unavailable modules (optional)
+	 * @return String: Response data
+	 */
+	public function makeModuleResponse( ResourceLoaderContext $context, 
+		array $modules, $missing = array() ) 
+	{
+		$out = '';
+		$exceptions = '';
+		if ( $modules === array() && $missing === array() ) {
+			return '/* No modules requested. Max made me put this here */';
+		}
+		
+		wfProfileIn( __METHOD__ );
+		// Pre-fetch blobs
+		if ( $context->shouldIncludeMessages() ) {
+			try {
+				$blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
+			} catch ( Exception $e ) {
+				// Add exception to the output as a comment
+				$exceptions .= "/*\n{$e->__toString()}\n*/\n";
+			}
+		} else {
+			$blobs = array();
+		}
+
+		// Generate output
+		foreach ( $modules as $name => $module ) {
+			wfProfileIn( __METHOD__ . '-' . $name );
+			try {
+				// Scripts
+				$scripts = '';
+				if ( $context->shouldIncludeScripts() ) {
+					// bug 27054: Append semicolon to prevent weird bugs
+					// caused by files not terminating their statements right
+					$scripts .= $module->getScript( $context ) . ";\n";
+				}
+
+				// Styles
+				$styles = array();
+				if ( $context->shouldIncludeStyles() ) {
+					$styles = $module->getStyles( $context );
+				}
+
+				// Messages
+				$messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
+
+				// Append output
+				switch ( $context->getOnly() ) {
+					case 'scripts':
+						$out .= $scripts;
+						break;
+					case 'styles':
+						$out .= self::makeCombinedStyles( $styles );
+						break;
+					case 'messages':
+						$out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
+						break;
+					default:
+						// Minify CSS before embedding in mediaWiki.loader.implement call
+						// (unless in debug mode)
+						if ( !$context->getDebug() ) {
+							foreach ( $styles as $media => $style ) {
+								$styles[$media] = $this->filter( 'minify-css', $style );
+							}
+						}
+						$out .= self::makeLoaderImplementScript( $name, $scripts, $styles,
+							new XmlJsCode( $messagesBlob ) );
+						break;
+				}
+			} catch ( Exception $e ) {
+				// Add exception to the output as a comment
+				$exceptions .= "/*\n{$e->__toString()}\n*/\n";
+
+				// Register module as missing
+				$missing[] = $name;
+				unset( $modules[$name] );
+			}
+			wfProfileOut( __METHOD__ . '-' . $name );
+		}
+
+		// Update module states
+		if ( $context->shouldIncludeScripts() ) {
+			// Set the state of modules loaded as only scripts to ready
+			if ( count( $modules ) && $context->getOnly() === 'scripts' 
+				&& !isset( $modules['startup'] ) ) 
+			{
+				$out .= self::makeLoaderStateScript( 
+					array_fill_keys( array_keys( $modules ), 'ready' ) );
+			}
+			// Set the state of modules which were requested but unavailable as missing
+			if ( is_array( $missing ) && count( $missing ) ) {
+				$out .= self::makeLoaderStateScript( array_fill_keys( $missing, 'missing' ) );
+			}
+		}
+
+		if ( !$context->getDebug() ) {
+			if ( $context->getOnly() === 'styles' ) {
+				$out = $this->filter( 'minify-css', $out );
+			} else {
+				$out = $this->filter( 'minify-js', $out );
+			}
+		}
+		
+		wfProfileOut( __METHOD__ );
+		return $exceptions . $out;
+	}
+
+	/* Static Methods */
+
+	/**
+	 * Returns JS code to call to mediaWiki.loader.implement for a module with 
+	 * given properties.
+	 *
+	 * @param $name Module name
+	 * @param $scripts Array: List of JavaScript code snippets to be executed after the 
+	 *     module is loaded
+	 * @param $styles Array: List of CSS strings keyed by media type
+	 * @param $messages Mixed: List of messages associated with this module. May either be an 
+	 *     associative array mapping message key to value, or a JSON-encoded message blob containing
+	 *     the same data, wrapped in an XmlJsCode object.
+	 */
+	public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
+		if ( is_array( $scripts ) ) {
+			$scripts = implode( $scripts, "\n" );
+		}
+		return Xml::encodeJsCall( 
+			'mediaWiki.loader.implement', 
+			array(
+				$name,
+				new XmlJsCode( "function( $, mw ) {{$scripts}}" ),
+				(object)$styles,
+				(object)$messages
+			) );
+	}
+
+	/**
+	 * Returns JS code which, when called, will register a given list of messages.
+	 *
+	 * @param $messages Mixed: Either an associative array mapping message key to value, or a
+	 *     JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
+	 */
+	public static function makeMessageSetScript( $messages ) {
+		return Xml::encodeJsCall( 'mediaWiki.messages.set', array( (object)$messages ) );
+	}
+
+	/**
+	 * Combines an associative array mapping media type to CSS into a 
+	 * single stylesheet with @media blocks.
+	 *
+	 * @param $styles Array: List of CSS strings keyed by media type
+	 */
+	public static function makeCombinedStyles( array $styles ) {
+		$out = '';
+		foreach ( $styles as $media => $style ) {
+			// Transform the media type based on request params and config
+			// The way that this relies on $wgRequest to propagate request params is slightly evil
+			$media = OutputPage::transformCssMedia( $media );
+			
+			if ( $media === null ) {
+				// Skip
+			} else if ( $media === '' || $media == 'all' ) {
+				// Don't output invalid or frivolous @media statements
+				$out .= "$style\n";
+			} else {
+				$out .= "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "\n}\n";
+			}
+		}
+		return $out;
+	}
+
+	/**
+	 * Returns a JS call to mediaWiki.loader.state, which sets the state of a 
+	 * module or modules to a given value. Has two calling conventions:
+	 *
+	 *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
+	 *         Set the state of a single module called $name to $state
+	 *
+	 *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
+	 *         Set the state of modules with the given names to the given states
+	 */
+	public static function makeLoaderStateScript( $name, $state = null ) {
+		if ( is_array( $name ) ) {
+			return Xml::encodeJsCall( 'mediaWiki.loader.state', array( $name ) );
+		} else {
+			return Xml::encodeJsCall( 'mediaWiki.loader.state', array( $name, $state ) );
+		}
+	}
+
+	/**
+	 * Returns JS code which calls the script given by $script. The script will
+	 * be called with local variables name, version, dependencies and group, 
+	 * which will have values corresponding to $name, $version, $dependencies 
+	 * and $group as supplied. 
+	 *
+	 * @param $name String: Module name
+	 * @param $version Integer: Module version number as a timestamp
+	 * @param $dependencies Array: List of module names on which this module depends
+	 * @param $group String: Group which the module is in.
+	 * @param $script String: JavaScript code
+	 */
+	public static function makeCustomLoaderScript( $name, $version, $dependencies, $group, $script ) {
+		$script = str_replace( "\n", "\n\t", trim( $script ) );
+		return Xml::encodeJsCall( 
+			"( function( name, version, dependencies, group ) {\n\t$script\n} )",
+			array( $name, $version, $dependencies, $group ) );
+	}
+
+	/**
+	 * Returns JS code which calls mediaWiki.loader.register with the given 
+	 * parameters. Has three calling conventions:
+	 *
+	 *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group ):
+	 *       Register a single module.
+	 *
+	 *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
+	 *       Register modules with the given names.
+	 *
+	 *   - ResourceLoader::makeLoaderRegisterScript( array(
+	 *        array( $name1, $version1, $dependencies1, $group1 ),
+	 *        array( $name2, $version2, $dependencies1, $group2 ),
+	 *        ...
+	 *     ) ):
+	 *        Registers modules with the given names and parameters.
+	 *
+	 * @param $name String: Module name
+	 * @param $version Integer: Module version number as a timestamp
+	 * @param $dependencies Array: List of module names on which this module depends
+	 * @param $group String: group which the module is in.
+	 */
+	public static function makeLoaderRegisterScript( $name, $version = null, 
+		$dependencies = null, $group = null ) 
+	{
+		if ( is_array( $name ) ) {
+			return Xml::encodeJsCall( 'mediaWiki.loader.register', array( $name ) );
+		} else {
+			$version = (int) $version > 1 ? (int) $version : 1;
+			return Xml::encodeJsCall( 'mediaWiki.loader.register', 
+				array( $name, $version, $dependencies, $group ) );
+		}
+	}
+
+	/**
+	 * Returns JS code which runs given JS code if the client-side framework is 
+	 * present.
+	 *
+	 * @param $script String: JavaScript code
+	 */
+	public static function makeLoaderConditionalScript( $script ) {
+		$script = str_replace( "\n", "\n\t", trim( $script ) );
+		return "if ( window.mediaWiki ) {\n\t$script\n}\n";
+	}
+
+	/**
+	 * Returns JS code which will set the MediaWiki configuration array to 
+	 * the given value.
+	 *
+	 * @param $configuration Array: List of configuration values keyed by variable name
+	 */
+	public static function makeConfigSetScript( array $configuration ) {
+		return Xml::encodeJsCall( 'mediaWiki.config.set', array( $configuration ) );
+	}
+	
+	/**
+	 * Convert an array of module names to a packed query string.
+	 * 
+	 * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
+	 * becomes 'foo.bar,baz|bar.baz,quux'
+	 * @param $modules array of module names (strings)
+	 * @return string Packed query string
+	 */
+	public static function makePackedModulesString( $modules ) {
+		$groups = array(); // array( prefix => array( suffixes ) )
+		foreach ( $modules as $module ) {
+			$pos = strrpos( $module, '.' );
+			$prefix = $pos === false ? '' : substr( $module, 0, $pos );
+			$suffix = $pos === false ? $module : substr( $module, $pos + 1 );
+			$groups[$prefix][] = $suffix;
+		}
+		
+		$arr = array();
+		foreach ( $groups as $prefix => $suffixes ) {
+			$p = $prefix === '' ? '' : $prefix . '.';
+			$arr[] = $p . implode( ',', $suffixes );
+		}
+		return implode( '|', $arr );
+	}
+	
+	/**
+	 * Determine whether debug mode was requested
+	 * Order of priority is 1) request param, 2) cookie, 3) $wg setting
+	 * @return bool
+	 */
+	public static function inDebugMode() {
+		global $wgRequest, $wgResourceLoaderDebug;
+		static $retval = null;
+		if ( !is_null( $retval ) )
+			return $retval;
+		return $retval = $wgRequest->getFuzzyBool( 'debug',
+			$wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug ) );
+	}
+}