X-Git-Url: https://scripts.mit.edu/gitweb/autoinstallsdev/mediawiki.git/blobdiff_plain/19e297c21b10b1b8a3acad5e73fc71dcb35db44a..6932310fd58ebef145fa01eb76edf7150284d8ea:/resources/src/mediawiki/mediawiki.js

diff --git a/resources/src/mediawiki/mediawiki.js b/resources/src/mediawiki/mediawiki.js
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+/**
+ * Base library for MediaWiki.
+ *
+ * Exposed globally as `mediaWiki` with `mw` as shortcut.
+ *
+ * @class mw
+ * @alternateClassName mediaWiki
+ * @singleton
+ */
+
+/* global mwNow */
+/* eslint-disable no-use-before-define */
+
+( function ( $ ) {
+	'use strict';
+
+	var mw, StringSet, log,
+		hasOwn = Object.prototype.hasOwnProperty,
+		slice = Array.prototype.slice,
+		trackCallbacks = $.Callbacks( 'memory' ),
+		trackHandlers = [],
+		trackQueue = [];
+
+	/**
+	 * FNV132 hash function
+	 *
+	 * This function implements the 32-bit version of FNV-1.
+	 * It is equivalent to hash( 'fnv132', ... ) in PHP, except
+	 * its output is base 36 rather than hex.
+	 * See <https://en.wikipedia.org/wiki/FNV_hash_function>
+	 *
+	 * @private
+	 * @param {string} str String to hash
+	 * @return {string} hash as an seven-character base 36 string
+	 */
+	function fnv132( str ) {
+		/* eslint-disable no-bitwise */
+		var hash = 0x811C9DC5,
+			i;
+
+		for ( i = 0; i < str.length; i++ ) {
+			hash += ( hash << 1 ) + ( hash << 4 ) + ( hash << 7 ) + ( hash << 8 ) + ( hash << 24 );
+			hash ^= str.charCodeAt( i );
+		}
+
+		hash = ( hash >>> 0 ).toString( 36 );
+		while ( hash.length < 7 ) {
+			hash = '0' + hash;
+		}
+
+		return hash;
+		/* eslint-enable no-bitwise */
+	}
+
+	function defineFallbacks() {
+		// <https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Set>
+		StringSet = window.Set || ( function () {
+			/**
+			 * @private
+			 * @class
+			 */
+			function StringSet() {
+				this.set = {};
+			}
+			StringSet.prototype.add = function ( value ) {
+				this.set[ value ] = true;
+			};
+			StringSet.prototype.has = function ( value ) {
+				return hasOwn.call( this.set, value );
+			};
+			return StringSet;
+		}() );
+	}
+
+	/**
+	 * Create an object that can be read from or written to via methods that allow
+	 * interaction both with single and multiple properties at once.
+	 *
+	 * @private
+	 * @class mw.Map
+	 *
+	 * @constructor
+	 * @param {boolean} [global=false] Whether to synchronise =values to the global
+	 *  window object (for backwards-compatibility with mw.config; T72470). Values are
+	 *  copied in one direction only. Changes to globals do not reflect in the map.
+	 */
+	function Map( global ) {
+		this.values = {};
+		if ( global === true ) {
+			// Override #set to also set the global variable
+			this.set = function ( selection, value ) {
+				var s;
+
+				if ( $.isPlainObject( selection ) ) {
+					for ( s in selection ) {
+						setGlobalMapValue( this, s, selection[ s ] );
+					}
+					return true;
+				}
+				if ( typeof selection === 'string' && arguments.length ) {
+					setGlobalMapValue( this, selection, value );
+					return true;
+				}
+				return false;
+			};
+		}
+	}
+
+	/**
+	 * Alias property to the global object.
+	 *
+	 * @private
+	 * @static
+	 * @param {mw.Map} map
+	 * @param {string} key
+	 * @param {Mixed} value
+	 */
+	function setGlobalMapValue( map, key, value ) {
+		map.values[ key ] = value;
+		log.deprecate(
+			window,
+			key,
+			value,
+			// Deprecation notice for mw.config globals (T58550, T72470)
+			map === mw.config && 'Use mw.config instead.'
+		);
+	}
+
+	Map.prototype = {
+		constructor: Map,
+
+		/**
+		 * Get the value of one or more keys.
+		 *
+		 * If called with no arguments, all values are returned.
+		 *
+		 * @param {string|Array} [selection] Key or array of keys to retrieve values for.
+		 * @param {Mixed} [fallback=null] Value for keys that don't exist.
+		 * @return {Mixed|Object|null} If selection was a string, returns the value,
+		 *  If selection was an array, returns an object of key/values.
+		 *  If no selection is passed, a new object with all key/values is returned.
+		 */
+		get: function ( selection, fallback ) {
+			var results, i;
+			fallback = arguments.length > 1 ? fallback : null;
+
+			if ( Array.isArray( selection ) ) {
+				results = {};
+				for ( i = 0; i < selection.length; i++ ) {
+					if ( typeof selection[ i ] === 'string' ) {
+						results[ selection[ i ] ] = hasOwn.call( this.values, selection[ i ] ) ?
+							this.values[ selection[ i ] ] :
+							fallback;
+					}
+				}
+				return results;
+			}
+
+			if ( typeof selection === 'string' ) {
+				return hasOwn.call( this.values, selection ) ?
+					this.values[ selection ] :
+					fallback;
+			}
+
+			if ( selection === undefined ) {
+				results = {};
+				for ( i in this.values ) {
+					results[ i ] = this.values[ i ];
+				}
+				return results;
+			}
+
+			// Invalid selection key
+			return fallback;
+		},
+
+		/**
+		 * Set one or more key/value pairs.
+		 *
+		 * @param {string|Object} selection Key to set value for, or object mapping keys to values
+		 * @param {Mixed} [value] Value to set (optional, only in use when key is a string)
+		 * @return {boolean} True on success, false on failure
+		 */
+		set: function ( selection, value ) {
+			var s;
+
+			if ( $.isPlainObject( selection ) ) {
+				for ( s in selection ) {
+					this.values[ s ] = selection[ s ];
+				}
+				return true;
+			}
+			if ( typeof selection === 'string' && arguments.length > 1 ) {
+				this.values[ selection ] = value;
+				return true;
+			}
+			return false;
+		},
+
+		/**
+		 * Check if one or more keys exist.
+		 *
+		 * @param {Mixed} selection Key or array of keys to check
+		 * @return {boolean} True if the key(s) exist
+		 */
+		exists: function ( selection ) {
+			var i;
+			if ( Array.isArray( selection ) ) {
+				for ( i = 0; i < selection.length; i++ ) {
+					if ( typeof selection[ i ] !== 'string' || !hasOwn.call( this.values, selection[ i ] ) ) {
+						return false;
+					}
+				}
+				return true;
+			}
+			return typeof selection === 'string' && hasOwn.call( this.values, selection );
+		}
+	};
+
+	/**
+	 * Object constructor for messages.
+	 *
+	 * Similar to the Message class in MediaWiki PHP.
+	 *
+	 * Format defaults to 'text'.
+	 *
+	 *     @example
+	 *
+	 *     var obj, str;
+	 *     mw.messages.set( {
+	 *         'hello': 'Hello world',
+	 *         'hello-user': 'Hello, $1!',
+	 *         'welcome-user': 'Welcome back to $2, $1! Last visit by $1: $3'
+	 *     } );
+	 *
+	 *     obj = new mw.Message( mw.messages, 'hello' );
+	 *     mw.log( obj.text() );
+	 *     // Hello world
+	 *
+	 *     obj = new mw.Message( mw.messages, 'hello-user', [ 'John Doe' ] );
+	 *     mw.log( obj.text() );
+	 *     // Hello, John Doe!
+	 *
+	 *     obj = new mw.Message( mw.messages, 'welcome-user', [ 'John Doe', 'Wikipedia', '2 hours ago' ] );
+	 *     mw.log( obj.text() );
+	 *     // Welcome back to Wikipedia, John Doe! Last visit by John Doe: 2 hours ago
+	 *
+	 *     // Using mw.message shortcut
+	 *     obj = mw.message( 'hello-user', 'John Doe' );
+	 *     mw.log( obj.text() );
+	 *     // Hello, John Doe!
+	 *
+	 *     // Using mw.msg shortcut
+	 *     str = mw.msg( 'hello-user', 'John Doe' );
+	 *     mw.log( str );
+	 *     // Hello, John Doe!
+	 *
+	 *     // Different formats
+	 *     obj = new mw.Message( mw.messages, 'hello-user', [ 'John "Wiki" <3 Doe' ] );
+	 *
+	 *     obj.format = 'text';
+	 *     str = obj.toString();
+	 *     // Same as:
+	 *     str = obj.text();
+	 *
+	 *     mw.log( str );
+	 *     // Hello, John "Wiki" <3 Doe!
+	 *
+	 *     mw.log( obj.escaped() );
+	 *     // Hello, John &quot;Wiki&quot; &lt;3 Doe!
+	 *
+	 * @class mw.Message
+	 *
+	 * @constructor
+	 * @param {mw.Map} map Message store
+	 * @param {string} key
+	 * @param {Array} [parameters]
+	 */
+	function Message( map, key, parameters ) {
+		this.format = 'text';
+		this.map = map;
+		this.key = key;
+		this.parameters = parameters === undefined ? [] : slice.call( parameters );
+		return this;
+	}
+
+	Message.prototype = {
+		/**
+		 * Get parsed contents of the message.
+		 *
+		 * The default parser does simple $N replacements and nothing else.
+		 * This may be overridden to provide a more complex message parser.
+		 * The primary override is in the mediawiki.jqueryMsg module.
+		 *
+		 * This function will not be called for nonexistent messages.
+		 *
+		 * @return {string} Parsed message
+		 */
+		parser: function () {
+			return mw.format.apply( null, [ this.map.get( this.key ) ].concat( this.parameters ) );
+		},
+
+		// eslint-disable-next-line valid-jsdoc
+		/**
+		 * Add (does not replace) parameters for `$N` placeholder values.
+		 *
+		 * @param {Array} parameters
+		 * @chainable
+		 */
+		params: function ( parameters ) {
+			var i;
+			for ( i = 0; i < parameters.length; i++ ) {
+				this.parameters.push( parameters[ i ] );
+			}
+			return this;
+		},
+
+		/**
+		 * Convert message object to its string form based on current format.
+		 *
+		 * @return {string} Message as a string in the current form, or `<key>` if key
+		 *  does not exist.
+		 */
+		toString: function () {
+			var text;
+
+			if ( !this.exists() ) {
+				// Use ⧼key⧽ as text if key does not exist
+				// Err on the side of safety, ensure that the output
+				// is always html safe in the event the message key is
+				// missing, since in that case its highly likely the
+				// message key is user-controlled.
+				// '⧼' is used instead of '<' to side-step any
+				// double-escaping issues.
+				// (Keep synchronised with Message::toString() in PHP.)
+				return '⧼' + mw.html.escape( this.key ) + '⧽';
+			}
+
+			if ( this.format === 'plain' || this.format === 'text' || this.format === 'parse' ) {
+				text = this.parser();
+			}
+
+			if ( this.format === 'escaped' ) {
+				text = this.parser();
+				text = mw.html.escape( text );
+			}
+
+			return text;
+		},
+
+		/**
+		 * Change format to 'parse' and convert message to string
+		 *
+		 * If jqueryMsg is loaded, this parses the message text from wikitext
+		 * (where supported) to HTML
+		 *
+		 * Otherwise, it is equivalent to plain.
+		 *
+		 * @return {string} String form of parsed message
+		 */
+		parse: function () {
+			this.format = 'parse';
+			return this.toString();
+		},
+
+		/**
+		 * Change format to 'plain' and convert message to string
+		 *
+		 * This substitutes parameters, but otherwise does not change the
+		 * message text.
+		 *
+		 * @return {string} String form of plain message
+		 */
+		plain: function () {
+			this.format = 'plain';
+			return this.toString();
+		},
+
+		/**
+		 * Change format to 'text' and convert message to string
+		 *
+		 * If jqueryMsg is loaded, {{-transformation is done where supported
+		 * (such as {{plural:}}, {{gender:}}, {{int:}}).
+		 *
+		 * Otherwise, it is equivalent to plain
+		 *
+		 * @return {string} String form of text message
+		 */
+		text: function () {
+			this.format = 'text';
+			return this.toString();
+		},
+
+		/**
+		 * Change the format to 'escaped' and convert message to string
+		 *
+		 * This is equivalent to using the 'text' format (see #text), then
+		 * HTML-escaping the output.
+		 *
+		 * @return {string} String form of html escaped message
+		 */
+		escaped: function () {
+			this.format = 'escaped';
+			return this.toString();
+		},
+
+		/**
+		 * Check if a message exists
+		 *
+		 * @see mw.Map#exists
+		 * @return {boolean}
+		 */
+		exists: function () {
+			return this.map.exists( this.key );
+		}
+	};
+
+	defineFallbacks();
+
+	/* eslint-disable no-console */
+	log = ( function () {
+		/**
+		 * Write a verbose message to the browser's console in debug mode.
+		 *
+		 * This method is mainly intended for verbose logging. It is a no-op in production mode.
+		 * In ResourceLoader debug mode, it will use the browser's console if available, with
+		 * fallback to creating a console interface in the DOM and logging messages there.
+		 *
+		 * See {@link mw.log} for other logging methods.
+		 *
+		 * @member mw
+		 * @param {...string} msg Messages to output to console.
+		 */
+		var log = function () {},
+			console = window.console;
+
+		// Note: Keep list of methods in sync with restoration in mediawiki.log.js
+		// when adding or removing mw.log methods below!
+
+		/**
+		 * Collection of methods to help log messages to the console.
+		 *
+		 * @class mw.log
+		 * @singleton
+		 */
+
+		/**
+		 * Write a message to the browser console's warning channel.
+		 *
+		 * This method is a no-op in browsers that don't implement the Console API.
+		 *
+		 * @param {...string} msg Messages to output to console
+		 */
+		log.warn = console && console.warn && Function.prototype.bind ?
+			Function.prototype.bind.call( console.warn, console ) :
+			$.noop;
+
+		/**
+		 * Write a message to the browser console's error channel.
+		 *
+		 * Most browsers also print a stacktrace when calling this method if the
+		 * argument is an Error object.
+		 *
+		 * This method is a no-op in browsers that don't implement the Console API.
+		 *
+		 * @since 1.26
+		 * @param {Error|...string} msg Messages to output to console
+		 */
+		log.error = console && console.error && Function.prototype.bind ?
+			Function.prototype.bind.call( console.error, console ) :
+			$.noop;
+
+		/**
+		 * Create a property on a host object that, when accessed, will produce
+		 * a deprecation warning in the console.
+		 *
+		 * @param {Object} obj Host object of deprecated property
+		 * @param {string} key Name of property to create in `obj`
+		 * @param {Mixed} val The value this property should return when accessed
+		 * @param {string} [msg] Optional text to include in the deprecation message
+		 * @param {string} [logName=key] Optional custom name for the feature.
+		 *  This is used instead of `key` in the message and `mw.deprecate` tracking.
+		 */
+		log.deprecate = !Object.defineProperty ? function ( obj, key, val ) {
+			obj[ key ] = val;
+		} : function ( obj, key, val, msg, logName ) {
+			var logged = new StringSet();
+			logName = logName || key;
+			msg = 'Use of "' + logName + '" is deprecated.' + ( msg ? ( ' ' + msg ) : '' );
+			function uniqueTrace() {
+				var trace = new Error().stack;
+				if ( logged.has( trace ) ) {
+					return false;
+				}
+				logged.add( trace );
+				return true;
+			}
+			// Support: Safari 5.0
+			// Throws "not supported on DOM Objects" for Node or Element objects (incl. document)
+			// Safari 4.0 doesn't have this method, and it was fixed in Safari 5.1.
+			try {
+				Object.defineProperty( obj, key, {
+					configurable: true,
+					enumerable: true,
+					get: function () {
+						if ( uniqueTrace() ) {
+							mw.track( 'mw.deprecate', logName );
+							mw.log.warn( msg );
+						}
+						return val;
+					},
+					set: function ( newVal ) {
+						if ( uniqueTrace() ) {
+							mw.track( 'mw.deprecate', logName );
+							mw.log.warn( msg );
+						}
+						val = newVal;
+					}
+				} );
+			} catch ( err ) {
+				obj[ key ] = val;
+			}
+		};
+
+		return log;
+	}() );
+	/* eslint-enable no-console */
+
+	/**
+	 * @class mw
+	 */
+	mw = {
+		redefineFallbacksForTest: function () {
+			if ( !window.QUnit ) {
+				throw new Error( 'Reset not allowed outside unit tests' );
+			}
+			defineFallbacks();
+		},
+
+		/**
+		 * Get the current time, measured in milliseconds since January 1, 1970 (UTC).
+		 *
+		 * On browsers that implement the Navigation Timing API, this function will produce floating-point
+		 * values with microsecond precision that are guaranteed to be monotonic. On all other browsers,
+		 * it will fall back to using `Date`.
+		 *
+		 * @return {number} Current time
+		 */
+		now: mwNow,
+		// mwNow is defined in startup.js
+
+		/**
+		 * Format a string. Replace $1, $2 ... $N with positional arguments.
+		 *
+		 * Used by Message#parser().
+		 *
+		 * @since 1.25
+		 * @param {string} formatString Format string
+		 * @param {...Mixed} parameters Values for $N replacements
+		 * @return {string} Formatted string
+		 */
+		format: function ( formatString ) {
+			var parameters = slice.call( arguments, 1 );
+			return formatString.replace( /\$(\d+)/g, function ( str, match ) {
+				var index = parseInt( match, 10 ) - 1;
+				return parameters[ index ] !== undefined ? parameters[ index ] : '$' + match;
+			} );
+		},
+
+		/**
+		 * Track an analytic event.
+		 *
+		 * This method provides a generic means for MediaWiki JavaScript code to capture state
+		 * information for analysis. Each logged event specifies a string topic name that describes
+		 * the kind of event that it is. Topic names consist of dot-separated path components,
+		 * arranged from most general to most specific. Each path component should have a clear and
+		 * well-defined purpose.
+		 *
+		 * Data handlers are registered via `mw.trackSubscribe`, and receive the full set of
+		 * events that match their subcription, including those that fired before the handler was
+		 * bound.
+		 *
+		 * @param {string} topic Topic name
+		 * @param {Object} [data] Data describing the event, encoded as an object
+		 */
+		track: function ( topic, data ) {
+			trackQueue.push( { topic: topic, timeStamp: mw.now(), data: data } );
+			trackCallbacks.fire( trackQueue );
+		},
+
+		/**
+		 * Register a handler for subset of analytic events, specified by topic.
+		 *
+		 * Handlers will be called once for each tracked event, including any events that fired before the
+		 * handler was registered; 'this' is set to a plain object with a 'timeStamp' property indicating
+		 * the exact time at which the event fired, a string 'topic' property naming the event, and a
+		 * 'data' property which is an object of event-specific data. The event topic and event data are
+		 * also passed to the callback as the first and second arguments, respectively.
+		 *
+		 * @param {string} topic Handle events whose name starts with this string prefix
+		 * @param {Function} callback Handler to call for each matching tracked event
+		 * @param {string} callback.topic
+		 * @param {Object} [callback.data]
+		 */
+		trackSubscribe: function ( topic, callback ) {
+			var seen = 0;
+			function handler( trackQueue ) {
+				var event;
+				for ( ; seen < trackQueue.length; seen++ ) {
+					event = trackQueue[ seen ];
+					if ( event.topic.indexOf( topic ) === 0 ) {
+						callback.call( event, event.topic, event.data );
+					}
+				}
+			}
+
+			trackHandlers.push( [ handler, callback ] );
+
+			trackCallbacks.add( handler );
+		},
+
+		/**
+		 * Stop handling events for a particular handler
+		 *
+		 * @param {Function} callback
+		 */
+		trackUnsubscribe: function ( callback ) {
+			trackHandlers = $.grep( trackHandlers, function ( fns ) {
+				if ( fns[ 1 ] === callback ) {
+					trackCallbacks.remove( fns[ 0 ] );
+					// Ensure the tuple is removed to avoid holding on to closures
+					return false;
+				}
+				return true;
+			} );
+		},
+
+		// Expose Map constructor
+		Map: Map,
+
+		// Expose Message constructor
+		Message: Message,
+
+		/**
+		 * Map of configuration values.
+		 *
+		 * Check out [the complete list of configuration values](https://www.mediawiki.org/wiki/Manual:Interface/JavaScript#mw.config)
+		 * on mediawiki.org.
+		 *
+		 * If `$wgLegacyJavaScriptGlobals` is true, this Map will add its values to the
+		 * global `window` object.
+		 *
+		 * @property {mw.Map} config
+		 */
+		// Dummy placeholder later assigned in ResourceLoaderStartUpModule
+		config: null,
+
+		/**
+		 * Empty object for third-party libraries, for cases where you don't
+		 * want to add a new global, or the global is bad and needs containment
+		 * or wrapping.
+		 *
+		 * @property
+		 */
+		libs: {},
+
+		/**
+		 * Access container for deprecated functionality that can be moved from
+		 * from their legacy location and attached to this object (e.g. a global
+		 * function that is deprecated and as stop-gap can be exposed through here).
+		 *
+		 * This was reserved for future use but never ended up being used.
+		 *
+		 * @deprecated since 1.22 Let deprecated identifiers keep their original name
+		 *  and use mw.log#deprecate to create an access container for tracking.
+		 * @property
+		 */
+		legacy: {},
+
+		/**
+		 * Store for messages.
+		 *
+		 * @property {mw.Map}
+		 */
+		messages: new Map(),
+
+		/**
+		 * Store for templates associated with a module.
+		 *
+		 * @property {mw.Map}
+		 */
+		templates: new Map(),
+
+		/**
+		 * Get a message object.
+		 *
+		 * Shortcut for `new mw.Message( mw.messages, key, parameters )`.
+		 *
+		 * @see mw.Message
+		 * @param {string} key Key of message to get
+		 * @param {...Mixed} parameters Values for $N replacements
+		 * @return {mw.Message}
+		 */
+		message: function ( key ) {
+			var parameters = slice.call( arguments, 1 );
+			return new Message( mw.messages, key, parameters );
+		},
+
+		/**
+		 * Get a message string using the (default) 'text' format.
+		 *
+		 * Shortcut for `mw.message( key, parameters... ).text()`.
+		 *
+		 * @see mw.Message
+		 * @param {string} key Key of message to get
+		 * @param {...Mixed} parameters Values for $N replacements
+		 * @return {string}
+		 */
+		msg: function () {
+			return mw.message.apply( mw.message, arguments ).toString();
+		},
+
+		// Expose mw.log
+		log: log,
+
+		/**
+		 * Client for ResourceLoader server end point.
+		 *
+		 * This client is in charge of maintaining the module registry and state
+		 * machine, initiating network (batch) requests for loading modules, as
+		 * well as dependency resolution and execution of source code.
+		 *
+		 * For more information, refer to
+		 * <https://www.mediawiki.org/wiki/ResourceLoader/Features>
+		 *
+		 * @class mw.loader
+		 * @singleton
+		 */
+		loader: ( function () {
+
+			/**
+			 * Fired via mw.track on various resource loading errors.
+			 *
+			 * @event resourceloader_exception
+			 * @param {Error|Mixed} e The error that was thrown. Almost always an Error
+			 *   object, but in theory module code could manually throw something else, and that
+			 *   might also end up here.
+			 * @param {string} [module] Name of the module which caused the error. Omitted if the
+			 *   error is not module-related or the module cannot be easily identified due to
+			 *   batched handling.
+			 * @param {string} source Source of the error. Possible values:
+			 *
+			 *   - style: stylesheet error (only affects old IE where a special style loading method
+			 *     is used)
+			 *   - load-callback: exception thrown by user callback
+			 *   - module-execute: exception thrown by module code
+			 *   - resolve: failed to sort dependencies for a module in mw.loader.load
+			 *   - store-eval: could not evaluate module code cached in localStorage
+			 *   - store-localstorage-init: localStorage or JSON parse error in mw.loader.store.init
+			 *   - store-localstorage-json: JSON conversion error in mw.loader.store.set
+			 *   - store-localstorage-update: localStorage or JSON conversion error in mw.loader.store.update
+			 */
+
+			/**
+			 * Fired via mw.track on resource loading error conditions.
+			 *
+			 * @event resourceloader_assert
+			 * @param {string} source Source of the error. Possible values:
+			 *
+			 *   - bug-T59567: failed to cache script due to an Opera function -> string conversion
+			 *     bug; see <https://phabricator.wikimedia.org/T59567> for details
+			 */
+
+			/**
+			 * Mapping of registered modules.
+			 *
+			 * See #implement and #execute for exact details on support for script, style and messages.
+			 *
+			 * Format:
+			 *
+			 *     {
+			 *         'moduleName': {
+			 *             // From mw.loader.register()
+			 *             'version': '########' (hash)
+			 *             'dependencies': ['required.foo', 'bar.also', ...], (or) function () {}
+			 *             'group': 'somegroup', (or) null
+			 *             'source': 'local', (or) 'anotherwiki'
+			 *             'skip': 'return !!window.Example', (or) null
+			 *             'module': export Object
+			 *
+			 *             // Set from execute() or mw.loader.state()
+			 *             'state': 'registered', 'loaded', 'loading', 'ready', 'error', or 'missing'
+			 *
+			 *             // Optionally added at run-time by mw.loader.implement()
+			 *             'skipped': true
+			 *             'script': closure, array of urls, or string
+			 *             'style': { ... } (see #execute)
+			 *             'messages': { 'key': 'value', ... }
+			 *         }
+			 *     }
+			 *
+			 * State machine:
+			 *
+			 * - `registered`:
+			 *    The module is known to the system but not yet required.
+			 *    Meta data is registered via mw.loader#register. Calls to that method are
+			 *    generated server-side by the startup module.
+			 * - `loading`:
+			 *    The module was required through mw.loader (either directly or as dependency of
+			 *    another module). The client will fetch module contents from the server.
+			 *    The contents are then stashed in the registry via mw.loader#implement.
+			 * - `loaded`:
+			 *    The module has been loaded from the server and stashed via mw.loader#implement.
+			 *    If the module has no more dependencies in-flight, the module will be executed
+			 *    immediately. Otherwise execution is deferred, controlled via #handlePending.
+			 * - `executing`:
+			 *    The module is being executed.
+			 * - `ready`:
+			 *    The module has been successfully executed.
+			 * - `error`:
+			 *    The module (or one of its dependencies) produced an error during execution.
+			 * - `missing`:
+			 *    The module was registered client-side and requested, but the server denied knowledge
+			 *    of the module's existence.
+			 *
+			 * @property
+			 * @private
+			 */
+			var registry = {},
+				// Mapping of sources, keyed by source-id, values are strings.
+				//
+				// Format:
+				//
+				//     {
+				//         'sourceId': 'http://example.org/w/load.php'
+				//     }
+				//
+				sources = {},
+
+				// For queueModuleScript()
+				handlingPendingRequests = false,
+				pendingRequests = [],
+
+				// List of modules to be loaded
+				queue = [],
+
+				/**
+				 * List of callback jobs waiting for modules to be ready.
+				 *
+				 * Jobs are created by #enqueue() and run by #handlePending().
+				 *
+				 * Typically when a job is created for a module, the job's dependencies contain
+				 * both the required module and all its recursive dependencies.
+				 *
+				 * Format:
+				 *
+				 *     {
+				 *         'dependencies': [ module names ],
+				 *         'ready': Function callback
+				 *         'error': Function callback
+				 *     }
+				 *
+				 * @property {Object[]} jobs
+				 * @private
+				 */
+				jobs = [],
+
+				// For getMarker()
+				marker = null,
+
+				// For addEmbeddedCSS()
+				cssBuffer = '',
+				cssBufferTimer = null,
+				cssCallbacks = $.Callbacks(),
+				rAF = window.requestAnimationFrame || setTimeout;
+
+			function getMarker() {
+				if ( !marker ) {
+					// Cache
+					marker = document.querySelector( 'meta[name="ResourceLoaderDynamicStyles"]' );
+					if ( !marker ) {
+						mw.log( 'Create <meta name="ResourceLoaderDynamicStyles"> dynamically' );
+						marker = $( '<meta>' ).attr( 'name', 'ResourceLoaderDynamicStyles' ).appendTo( 'head' )[ 0 ];
+					}
+				}
+				return marker;
+			}
+
+			/**
+			 * Create a new style element and add it to the DOM.
+			 *
+			 * @private
+			 * @param {string} text CSS text
+			 * @param {Node} [nextNode] The element where the style tag
+			 *  should be inserted before
+			 * @return {HTMLElement} Reference to the created style element
+			 */
+			function newStyleTag( text, nextNode ) {
+				var s = document.createElement( 'style' );
+
+				s.appendChild( document.createTextNode( text ) );
+				if ( nextNode && nextNode.parentNode ) {
+					nextNode.parentNode.insertBefore( s, nextNode );
+				} else {
+					document.getElementsByTagName( 'head' )[ 0 ].appendChild( s );
+				}
+
+				return s;
+			}
+
+			/**
+			 * Add a bit of CSS text to the current browser page.
+			 *
+			 * The CSS will be appended to an existing ResourceLoader-created `<style>` tag
+			 * or create a new one based on whether the given `cssText` is safe for extension.
+			 *
+			 * @private
+			 * @param {string} [cssText=cssBuffer] If called without cssText,
+			 *  the internal buffer will be inserted instead.
+			 * @param {Function} [callback]
+			 */
+			function addEmbeddedCSS( cssText, callback ) {
+				function fireCallbacks() {
+					var oldCallbacks = cssCallbacks;
+					// Reset cssCallbacks variable so it's not polluted by any calls to
+					// addEmbeddedCSS() from one of the callbacks (T105973)
+					cssCallbacks = $.Callbacks();
+					oldCallbacks.fire().empty();
+				}
+
+				if ( callback ) {
+					cssCallbacks.add( callback );
+				}
+
+				// Yield once before creating the <style> tag. This lets multiple stylesheets
+				// accumulate into one buffer, allowing us to reduce how often new stylesheets
+				// are inserted in the browser. Appending a stylesheet and waiting for the
+				// browser to repaint is fairly expensive. (T47810)
+				if ( cssText ) {
+					// Don't extend the buffer if the item needs its own stylesheet.
+					// Keywords like `@import` are only valid at the start of a stylesheet (T37562).
+					if ( !cssBuffer || cssText.slice( 0, '@import'.length ) !== '@import' ) {
+						// Linebreak for somewhat distinguishable sections
+						cssBuffer += '\n' + cssText;
+						if ( !cssBufferTimer ) {
+							cssBufferTimer = rAF( function () {
+								// Wrap in anonymous function that takes no arguments
+								// Support: Firefox < 13
+								// Firefox 12 has non-standard behaviour of passing a number
+								// as first argument to a setTimeout callback.
+								// http://benalman.com/news/2009/07/the-mysterious-firefox-settime/
+								addEmbeddedCSS();
+							} );
+						}
+						return;
+					}
+
+				// This is a scheduled flush for the buffer
+				} else {
+					cssBufferTimer = null;
+					cssText = cssBuffer;
+					cssBuffer = '';
+				}
+
+				$( newStyleTag( cssText, getMarker() ) );
+
+				fireCallbacks();
+			}
+
+			/**
+			 * @private
+			 * @param {Array} modules List of module names
+			 * @return {string} Hash of concatenated version hashes.
+			 */
+			function getCombinedVersion( modules ) {
+				var hashes = modules.map( function ( module ) {
+					return registry[ module ].version;
+				} );
+				return fnv132( hashes.join( '' ) );
+			}
+
+			/**
+			 * Determine whether all dependencies are in state 'ready', which means we may
+			 * execute the module or job now.
+			 *
+			 * @private
+			 * @param {Array} modules Names of modules to be checked
+			 * @return {boolean} True if all modules are in state 'ready', false otherwise
+			 */
+			function allReady( modules ) {
+				var i;
+				for ( i = 0; i < modules.length; i++ ) {
+					if ( mw.loader.getState( modules[ i ] ) !== 'ready' ) {
+						return false;
+					}
+				}
+				return true;
+			}
+
+			/**
+			 * Determine whether all dependencies are in state 'ready', which means we may
+			 * execute the module or job now.
+			 *
+			 * @private
+			 * @param {Array} modules Names of modules to be checked
+			 * @return {boolean} True if no modules are in state 'error' or 'missing', false otherwise
+			 */
+			function anyFailed( modules ) {
+				var i, state;
+				for ( i = 0; i < modules.length; i++ ) {
+					state = mw.loader.getState( modules[ i ] );
+					if ( state === 'error' || state === 'missing' ) {
+						return true;
+					}
+				}
+				return false;
+			}
+
+			/**
+			 * A module has entered state 'ready', 'error', or 'missing'. Automatically update
+			 * pending jobs and modules that depend upon this module. If the given module failed,
+			 * propagate the 'error' state up the dependency tree. Otherwise, go ahead and execute
+			 * all jobs/modules now having their dependencies satisfied.
+			 *
+			 * Jobs that depend on a failed module, will have their error callback ran (if any).
+			 *
+			 * @private
+			 * @param {string} module Name of module that entered one of the states 'ready', 'error', or 'missing'.
+			 */
+			function handlePending( module ) {
+				var j, job, hasErrors, m, stateChange;
+
+				if ( registry[ module ].state === 'error' || registry[ module ].state === 'missing' ) {
+					// If the current module failed, mark all dependent modules also as failed.
+					// Iterate until steady-state to propagate the error state upwards in the
+					// dependency tree.
+					do {
+						stateChange = false;
+						for ( m in registry ) {
+							if ( registry[ m ].state !== 'error' && registry[ m ].state !== 'missing' ) {
+								if ( anyFailed( registry[ m ].dependencies ) ) {
+									registry[ m ].state = 'error';
+									stateChange = true;
+								}
+							}
+						}
+					} while ( stateChange );
+				}
+
+				// Execute all jobs whose dependencies are either all satisfied or contain at least one failed module.
+				for ( j = 0; j < jobs.length; j++ ) {
+					hasErrors = anyFailed( jobs[ j ].dependencies );
+					if ( hasErrors || allReady( jobs[ j ].dependencies ) ) {
+						// All dependencies satisfied, or some have errors
+						job = jobs[ j ];
+						jobs.splice( j, 1 );
+						j -= 1;
+						try {
+							if ( hasErrors ) {
+								if ( typeof job.error === 'function' ) {
+									job.error( new Error( 'Module ' + module + ' has failed dependencies' ), [ module ] );
+								}
+							} else {
+								if ( typeof job.ready === 'function' ) {
+									job.ready();
+								}
+							}
+						} catch ( e ) {
+							// A user-defined callback raised an exception.
+							// Swallow it to protect our state machine!
+							mw.track( 'resourceloader.exception', { exception: e, module: module, source: 'load-callback' } );
+						}
+					}
+				}
+
+				if ( registry[ module ].state === 'ready' ) {
+					// The current module became 'ready'. Set it in the module store, and recursively execute all
+					// dependent modules that are loaded and now have all dependencies satisfied.
+					mw.loader.store.set( module, registry[ module ] );
+					for ( m in registry ) {
+						if ( registry[ m ].state === 'loaded' && allReady( registry[ m ].dependencies ) ) {
+							execute( m );
+						}
+					}
+				}
+			}
+
+			/**
+			 * Resolve dependencies and detect circular references.
+			 *
+			 * @private
+			 * @param {string} module Name of the top-level module whose dependencies shall be
+			 *  resolved and sorted.
+			 * @param {Array} resolved Returns a topological sort of the given module and its
+			 *  dependencies, such that later modules depend on earlier modules. The array
+			 *  contains the module names. If the array contains already some module names,
+			 *  this function appends its result to the pre-existing array.
+			 * @param {StringSet} [unresolved] Used to track the current dependency
+			 *  chain, and to report loops in the dependency graph.
+			 * @throws {Error} If any unregistered module or a dependency loop is encountered
+			 */
+			function sortDependencies( module, resolved, unresolved ) {
+				var i, deps, skip;
+
+				if ( !hasOwn.call( registry, module ) ) {
+					throw new Error( 'Unknown dependency: ' + module );
+				}
+
+				if ( registry[ module ].skip !== null ) {
+					// eslint-disable-next-line no-new-func
+					skip = new Function( registry[ module ].skip );
+					registry[ module ].skip = null;
+					if ( skip() ) {
+						registry[ module ].skipped = true;
+						registry[ module ].dependencies = [];
+						registry[ module ].state = 'ready';
+						handlePending( module );
+						return;
+					}
+				}
+
+				// Resolves dynamic loader function and replaces it with its own results
+				if ( typeof registry[ module ].dependencies === 'function' ) {
+					registry[ module ].dependencies = registry[ module ].dependencies();
+					// Ensures the module's dependencies are always in an array
+					if ( typeof registry[ module ].dependencies !== 'object' ) {
+						registry[ module ].dependencies = [ registry[ module ].dependencies ];
+					}
+				}
+				if ( $.inArray( module, resolved ) !== -1 ) {
+					// Module already resolved; nothing to do
+					return;
+				}
+				// Create unresolved if not passed in
+				if ( !unresolved ) {
+					unresolved = new StringSet();
+				}
+				// Tracks down dependencies
+				deps = registry[ module ].dependencies;
+				for ( i = 0; i < deps.length; i++ ) {
+					if ( $.inArray( deps[ i ], resolved ) === -1 ) {
+						if ( unresolved.has( deps[ i ] ) ) {
+							throw new Error( mw.format(
+								'Circular reference detected: $1 -> $2',
+								module,
+								deps[ i ]
+							) );
+						}
+
+						unresolved.add( module );
+						sortDependencies( deps[ i ], resolved, unresolved );
+					}
+				}
+				resolved.push( module );
+			}
+
+			/**
+			 * Get names of module that a module depends on, in their proper dependency order.
+			 *
+			 * @private
+			 * @param {string[]} modules Array of string module names
+			 * @return {Array} List of dependencies, including 'module'.
+			 * @throws {Error} If an unregistered module or a dependency loop is encountered
+			 */
+			function resolve( modules ) {
+				var i, resolved = [];
+				for ( i = 0; i < modules.length; i++ ) {
+					sortDependencies( modules[ i ], resolved );
+				}
+				return resolved;
+			}
+
+			/**
+			 * Like #resolve(), except it will silently ignore modules that
+			 * are missing or have missing dependencies.
+			 *
+			 * @private
+			 * @param {string[]} modules Array of string module names
+			 * @return {Array} List of dependencies.
+			 */
+			function resolveStubbornly( modules ) {
+				var i, saved, resolved = [];
+				for ( i = 0; i < modules.length; i++ ) {
+					saved = resolved.slice();
+					try {
+						sortDependencies( modules[ i ], resolved );
+					} catch ( err ) {
+						// This module is unknown or has unknown dependencies.
+						// Undo any incomplete resolutions made and keep going.
+						resolved = saved;
+						mw.track( 'resourceloader.exception', {
+							exception: err,
+							source: 'resolve'
+						} );
+					}
+				}
+				return resolved;
+			}
+
+			/**
+			 * Load and execute a script.
+			 *
+			 * @private
+			 * @param {string} src URL to script, will be used as the src attribute in the script tag
+			 * @return {jQuery.Promise}
+			 */
+			function addScript( src ) {
+				return $.ajax( {
+					url: src,
+					dataType: 'script',
+					// Force jQuery behaviour to be for crossDomain. Otherwise jQuery would use
+					// XHR for a same domain request instead of <script>, which changes the request
+					// headers (potentially missing a cache hit), and reduces caching in general
+					// since browsers cache XHR much less (if at all). And XHR means we retrieve
+					// text, so we'd need to $.globalEval, which then messes up line numbers.
+					crossDomain: true,
+					cache: true
+				} );
+			}
+
+			/**
+			 * Queue the loading and execution of a script for a particular module.
+			 *
+			 * @private
+			 * @param {string} src URL of the script
+			 * @param {string} [moduleName] Name of currently executing module
+			 * @return {jQuery.Promise}
+			 */
+			function queueModuleScript( src, moduleName ) {
+				var r = $.Deferred();
+
+				pendingRequests.push( function () {
+					if ( moduleName && hasOwn.call( registry, moduleName ) ) {
+						// Emulate runScript() part of execute()
+						window.require = mw.loader.require;
+						window.module = registry[ moduleName ].module;
+					}
+					addScript( src ).always( function () {
+						// 'module.exports' should not persist after the file is executed to
+						// avoid leakage to unrelated code. 'require' should be kept, however,
+						// as asynchronous access to 'require' is allowed and expected. (T144879)
+						delete window.module;
+						r.resolve();
+
+						// Start the next one (if any)
+						if ( pendingRequests[ 0 ] ) {
+							pendingRequests.shift()();
+						} else {
+							handlingPendingRequests = false;
+						}
+					} );
+				} );
+				if ( !handlingPendingRequests && pendingRequests[ 0 ] ) {
+					handlingPendingRequests = true;
+					pendingRequests.shift()();
+				}
+				return r.promise();
+			}
+
+			/**
+			 * Utility function for execute()
+			 *
+			 * @ignore
+			 * @param {string} [media] Media attribute
+			 * @param {string} url URL
+			 */
+			function addLink( media, url ) {
+				var el = document.createElement( 'link' );
+
+				el.rel = 'stylesheet';
+				if ( media && media !== 'all' ) {
+					el.media = media;
+				}
+				// If you end up here from an IE exception "SCRIPT: Invalid property value.",
+				// see #addEmbeddedCSS, T33676, T43331, and T49277 for details.
+				el.href = url;
+
+				$( getMarker() ).before( el );
+			}
+
+			/**
+			 * Executes a loaded module, making it ready to use
+			 *
+			 * @private
+			 * @param {string} module Module name to execute
+			 */
+			function execute( module ) {
+				var key, value, media, i, urls, cssHandle, checkCssHandles, runScript,
+					cssHandlesRegistered = false;
+
+				if ( !hasOwn.call( registry, module ) ) {
+					throw new Error( 'Module has not been registered yet: ' + module );
+				}
+				if ( registry[ module ].state !== 'loaded' ) {
+					throw new Error( 'Module in state "' + registry[ module ].state + '" may not be executed: ' + module );
+				}
+
+				registry[ module ].state = 'executing';
+
+				runScript = function () {
+					var script, markModuleReady, nestedAddScript;
+
+					script = registry[ module ].script;
+					markModuleReady = function () {
+						registry[ module ].state = 'ready';
+						handlePending( module );
+					};
+					nestedAddScript = function ( arr, callback, i ) {
+						// Recursively call queueModuleScript() in its own callback
+						// for each element of arr.
+						if ( i >= arr.length ) {
+							// We're at the end of the array
+							callback();
+							return;
+						}
+
+						queueModuleScript( arr[ i ], module ).always( function () {
+							nestedAddScript( arr, callback, i + 1 );
+						} );
+					};
+
+					try {
+						if ( Array.isArray( script ) ) {
+							nestedAddScript( script, markModuleReady, 0 );
+						} else if ( typeof script === 'function' ) {
+							// Pass jQuery twice so that the signature of the closure which wraps
+							// the script can bind both '$' and 'jQuery'.
+							script( $, $, mw.loader.require, registry[ module ].module );
+							markModuleReady();
+
+						} else if ( typeof script === 'string' ) {
+							// Site and user modules are legacy scripts that run in the global scope.
+							// This is transported as a string instead of a function to avoid needing
+							// to use string manipulation to undo the function wrapper.
+							$.globalEval( script );
+							markModuleReady();
+
+						} else {
+							// Module without script
+							markModuleReady();
+						}
+					} catch ( e ) {
+						// Use mw.track instead of mw.log because these errors are common in production mode
+						// (e.g. undefined variable), and mw.log is only enabled in debug mode.
+						registry[ module ].state = 'error';
+						mw.track( 'resourceloader.exception', { exception: e, module: module, source: 'module-execute' } );
+						handlePending( module );
+					}
+				};
+
+				// Add localizations to message system
+				if ( registry[ module ].messages ) {
+					mw.messages.set( registry[ module ].messages );
+				}
+
+				// Initialise templates
+				if ( registry[ module ].templates ) {
+					mw.templates.set( module, registry[ module ].templates );
+				}
+
+				// Make sure we don't run the scripts until all stylesheet insertions have completed.
+				( function () {
+					var pending = 0;
+					checkCssHandles = function () {
+						// cssHandlesRegistered ensures we don't take off too soon, e.g. when
+						// one of the cssHandles is fired while we're still creating more handles.
+						if ( cssHandlesRegistered && pending === 0 && runScript ) {
+							if ( module === 'user' ) {
+								// Implicit dependency on the site module. Not real dependency because
+								// it should run after 'site' regardless of whether it succeeds or fails.
+								mw.loader.using( [ 'site' ] ).always( runScript );
+							} else {
+								runScript();
+							}
+							runScript = undefined; // Revoke
+						}
+					};
+					cssHandle = function () {
+						var check = checkCssHandles;
+						pending++;
+						return function () {
+							if ( check ) {
+								pending--;
+								check();
+								check = undefined; // Revoke
+							}
+						};
+					};
+				}() );
+
+				// Process styles (see also mw.loader.implement)
+				// * back-compat: { <media>: css }
+				// * back-compat: { <media>: [url, ..] }
+				// * { "css": [css, ..] }
+				// * { "url": { <media>: [url, ..] } }
+				if ( registry[ module ].style ) {
+					for ( key in registry[ module ].style ) {
+						value = registry[ module ].style[ key ];
+						media = undefined;
+
+						if ( key !== 'url' && key !== 'css' ) {
+							// Backwards compatibility, key is a media-type
+							if ( typeof value === 'string' ) {
+								// back-compat: { <media>: css }
+								// Ignore 'media' because it isn't supported (nor was it used).
+								// Strings are pre-wrapped in "@media". The media-type was just ""
+								// (because it had to be set to something).
+								// This is one of the reasons why this format is no longer used.
+								addEmbeddedCSS( value, cssHandle() );
+							} else {
+								// back-compat: { <media>: [url, ..] }
+								media = key;
+								key = 'bc-url';
+							}
+						}
+
+						// Array of css strings in key 'css',
+						// or back-compat array of urls from media-type
+						if ( Array.isArray( value ) ) {
+							for ( i = 0; i < value.length; i++ ) {
+								if ( key === 'bc-url' ) {
+									// back-compat: { <media>: [url, ..] }
+									addLink( media, value[ i ] );
+								} else if ( key === 'css' ) {
+									// { "css": [css, ..] }
+									addEmbeddedCSS( value[ i ], cssHandle() );
+								}
+							}
+						// Not an array, but a regular object
+						// Array of urls inside media-type key
+						} else if ( typeof value === 'object' ) {
+							// { "url": { <media>: [url, ..] } }
+							for ( media in value ) {
+								urls = value[ media ];
+								for ( i = 0; i < urls.length; i++ ) {
+									addLink( media, urls[ i ] );
+								}
+							}
+						}
+					}
+				}
+
+				// Kick off.
+				cssHandlesRegistered = true;
+				checkCssHandles();
+			}
+
+			/**
+			 * Add one or more modules to the module load queue.
+			 *
+			 * See also #work().
+			 *
+			 * @private
+			 * @param {string|string[]} dependencies Module name or array of string module names
+			 * @param {Function} [ready] Callback to execute when all dependencies are ready
+			 * @param {Function} [error] Callback to execute when any dependency fails
+			 */
+			function enqueue( dependencies, ready, error ) {
+				// Allow calling by single module name
+				if ( typeof dependencies === 'string' ) {
+					dependencies = [ dependencies ];
+				}
+
+				// Add ready and error callbacks if they were given
+				if ( ready !== undefined || error !== undefined ) {
+					jobs.push( {
+						// Narrow down the list to modules that are worth waiting for
+						dependencies: $.grep( dependencies, function ( module ) {
+							var state = mw.loader.getState( module );
+							return state === 'registered' || state === 'loaded' || state === 'loading' || state === 'executing';
+						} ),
+						ready: ready,
+						error: error
+					} );
+				}
+
+				$.each( dependencies, function ( idx, module ) {
+					var state = mw.loader.getState( module );
+					// Only queue modules that are still in the initial 'registered' state
+					// (not ones already loading, ready or error).
+					if ( state === 'registered' && $.inArray( module, queue ) === -1 ) {
+						// Private modules must be embedded in the page. Don't bother queuing
+						// these as the server will deny them anyway (T101806).
+						if ( registry[ module ].group === 'private' ) {
+							registry[ module ].state = 'error';
+							handlePending( module );
+							return;
+						}
+						queue.push( module );
+					}
+				} );
+
+				mw.loader.work();
+			}
+
+			function sortQuery( o ) {
+				var key,
+					sorted = {},
+					a = [];
+
+				for ( key in o ) {
+					a.push( key );
+				}
+				a.sort();
+				for ( key = 0; key < a.length; key++ ) {
+					sorted[ a[ key ] ] = o[ a[ key ] ];
+				}
+				return sorted;
+			}
+
+			/**
+			 * Converts a module map of the form { foo: [ 'bar', 'baz' ], bar: [ 'baz, 'quux' ] }
+			 * to a query string of the form foo.bar,baz|bar.baz,quux
+			 *
+			 * @private
+			 * @param {Object} moduleMap Module map
+			 * @return {string} Module query string
+			 */
+			function buildModulesString( moduleMap ) {
+				var p, prefix,
+					arr = [];
+
+				for ( prefix in moduleMap ) {
+					p = prefix === '' ? '' : prefix + '.';
+					arr.push( p + moduleMap[ prefix ].join( ',' ) );
+				}
+				return arr.join( '|' );
+			}
+
+			/**
+			 * Make a network request to load modules from the server.
+			 *
+			 * @private
+			 * @param {Object} moduleMap Module map, see #buildModulesString
+			 * @param {Object} currReqBase Object with other parameters (other than 'modules') to use in the request
+			 * @param {string} sourceLoadScript URL of load.php
+			 */
+			function doRequest( moduleMap, currReqBase, sourceLoadScript ) {
+				// Optimisation: Inherit (Object.create), not copy ($.extend)
+				var query = Object.create( currReqBase );
+				query.modules = buildModulesString( moduleMap );
+				query = sortQuery( query );
+				addScript( sourceLoadScript + '?' + $.param( query ) );
+			}
+
+			/**
+			 * Resolve indexed dependencies.
+			 *
+			 * ResourceLoader uses an optimization to save space which replaces module names in
+			 * dependency lists with the index of that module within the array of module
+			 * registration data if it exists. The benefit is a significant reduction in the data
+			 * size of the startup module. This function changes those dependency lists back to
+			 * arrays of strings.
+			 *
+			 * @private
+			 * @param {Array} modules Modules array
+			 */
+			function resolveIndexedDependencies( modules ) {
+				var i, j, deps;
+				function resolveIndex( dep ) {
+					return typeof dep === 'number' ? modules[ dep ][ 0 ] : dep;
+				}
+				for ( i = 0; i < modules.length; i++ ) {
+					deps = modules[ i ][ 2 ];
+					if ( deps ) {
+						for ( j = 0; j < deps.length; j++ ) {
+							deps[ j ] = resolveIndex( deps[ j ] );
+						}
+					}
+				}
+			}
+
+			/**
+			 * Create network requests for a batch of modules.
+			 *
+			 * This is an internal method for #work(). This must not be called directly
+			 * unless the modules are already registered, and no request is in progress,
+			 * and the module state has already been set to `loading`.
+			 *
+			 * @private
+			 * @param {string[]} batch
+			 */
+			function batchRequest( batch ) {
+				var reqBase, splits, maxQueryLength, b, bSource, bGroup, bSourceGroup,
+					source, group, i, modules, sourceLoadScript,
+					currReqBase, currReqBaseLength, moduleMap, l,
+					lastDotIndex, prefix, suffix, bytesAdded;
+
+				if ( !batch.length ) {
+					return;
+				}
+
+				// Always order modules alphabetically to help reduce cache
+				// misses for otherwise identical content.
+				batch.sort();
+
+				// Build a list of query parameters common to all requests
+				reqBase = {
+					skin: mw.config.get( 'skin' ),
+					lang: mw.config.get( 'wgUserLanguage' ),
+					debug: mw.config.get( 'debug' )
+				};
+				maxQueryLength = mw.config.get( 'wgResourceLoaderMaxQueryLength', 2000 );
+
+				// Split module list by source and by group.
+				splits = {};
+				for ( b = 0; b < batch.length; b++ ) {
+					bSource = registry[ batch[ b ] ].source;
+					bGroup = registry[ batch[ b ] ].group;
+					if ( !hasOwn.call( splits, bSource ) ) {
+						splits[ bSource ] = {};
+					}
+					if ( !hasOwn.call( splits[ bSource ], bGroup ) ) {
+						splits[ bSource ][ bGroup ] = [];
+					}
+					bSourceGroup = splits[ bSource ][ bGroup ];
+					bSourceGroup.push( batch[ b ] );
+				}
+
+				for ( source in splits ) {
+
+					sourceLoadScript = sources[ source ];
+
+					for ( group in splits[ source ] ) {
+
+						// Cache access to currently selected list of
+						// modules for this group from this source.
+						modules = splits[ source ][ group ];
+
+						// Optimisation: Inherit (Object.create), not copy ($.extend)
+						currReqBase = Object.create( reqBase );
+						currReqBase.version = getCombinedVersion( modules );
+
+						// For user modules append a user name to the query string.
+						if ( group === 'user' && mw.config.get( 'wgUserName' ) !== null ) {
+							currReqBase.user = mw.config.get( 'wgUserName' );
+						}
+						currReqBaseLength = $.param( currReqBase ).length;
+						// We may need to split up the request to honor the query string length limit,
+						// so build it piece by piece.
+						l = currReqBaseLength + 9; // '&modules='.length == 9
+
+						moduleMap = {}; // { prefix: [ suffixes ] }
+
+						for ( i = 0; i < modules.length; i++ ) {
+							// Determine how many bytes this module would add to the query string
+							lastDotIndex = modules[ i ].lastIndexOf( '.' );
+
+							// If lastDotIndex is -1, substr() returns an empty string
+							prefix = modules[ i ].substr( 0, lastDotIndex );
+							suffix = modules[ i ].slice( lastDotIndex + 1 );
+
+							bytesAdded = hasOwn.call( moduleMap, prefix ) ?
+								suffix.length + 3 : // '%2C'.length == 3
+								modules[ i ].length + 3; // '%7C'.length == 3
+
+							// If the url would become too long, create a new one,
+							// but don't create empty requests
+							if ( maxQueryLength > 0 && !$.isEmptyObject( moduleMap ) && l + bytesAdded > maxQueryLength ) {
+								// This url would become too long, create a new one, and start the old one
+								doRequest( moduleMap, currReqBase, sourceLoadScript );
+								moduleMap = {};
+								l = currReqBaseLength + 9;
+								mw.track( 'resourceloader.splitRequest', { maxQueryLength: maxQueryLength } );
+							}
+							if ( !hasOwn.call( moduleMap, prefix ) ) {
+								moduleMap[ prefix ] = [];
+							}
+							moduleMap[ prefix ].push( suffix );
+							l += bytesAdded;
+						}
+						// If there's anything left in moduleMap, request that too
+						if ( !$.isEmptyObject( moduleMap ) ) {
+							doRequest( moduleMap, currReqBase, sourceLoadScript );
+						}
+					}
+				}
+			}
+
+			/**
+			 * @private
+			 * @param {string[]} implementations Array containing pieces of JavaScript code in the
+			 *  form of calls to mw.loader#implement().
+			 * @param {Function} cb Callback in case of failure
+			 * @param {Error} cb.err
+			 */
+			function asyncEval( implementations, cb ) {
+				if ( !implementations.length ) {
+					return;
+				}
+				mw.requestIdleCallback( function () {
+					try {
+						$.globalEval( implementations.join( ';' ) );
+					} catch ( err ) {
+						cb( err );
+					}
+				} );
+			}
+
+			/**
+			 * Make a versioned key for a specific module.
+			 *
+			 * @private
+			 * @param {string} module Module name
+			 * @return {string|null} Module key in format '`[name]@[version]`',
+			 *  or null if the module does not exist
+			 */
+			function getModuleKey( module ) {
+				return hasOwn.call( registry, module ) ?
+					( module + '@' + registry[ module ].version ) : null;
+			}
+
+			/**
+			 * @private
+			 * @param {string} key Module name or '`[name]@[version]`'
+			 * @return {Object}
+			 */
+			function splitModuleKey( key ) {
+				var index = key.indexOf( '@' );
+				if ( index === -1 ) {
+					return { name: key };
+				}
+				return {
+					name: key.slice( 0, index ),
+					version: key.slice( index + 1 )
+				};
+			}
+
+			/* Public Members */
+			return {
+				/**
+				 * The module registry is exposed as an aid for debugging and inspecting page
+				 * state; it is not a public interface for modifying the registry.
+				 *
+				 * @see #registry
+				 * @property
+				 * @private
+				 */
+				moduleRegistry: registry,
+
+				/**
+				 * @inheritdoc #newStyleTag
+				 * @method
+				 */
+				addStyleTag: newStyleTag,
+
+				/**
+				 * Start loading of all queued module dependencies.
+				 *
+				 * @protected
+				 */
+				work: function () {
+					var q, batch, implementations, sourceModules;
+
+					batch = [];
+
+					// Appends a list of modules from the queue to the batch
+					for ( q = 0; q < queue.length; q++ ) {
+						// Only load modules which are registered
+						if ( hasOwn.call( registry, queue[ q ] ) && registry[ queue[ q ] ].state === 'registered' ) {
+							// Prevent duplicate entries
+							if ( $.inArray( queue[ q ], batch ) === -1 ) {
+								batch.push( queue[ q ] );
+								// Mark registered modules as loading
+								registry[ queue[ q ] ].state = 'loading';
+							}
+						}
+					}
+
+					// Now that the queue has been processed into a batch, clear the queue.
+					// This MUST happen before we initiate any eval or network request. Otherwise,
+					// it is possible for a cached script to instantly trigger the same work queue
+					// again; all before we've cleared it causing each request to include modules
+					// which are already loaded.
+					queue = [];
+
+					if ( !batch.length ) {
+						return;
+					}
+
+					mw.loader.store.init();
+					if ( mw.loader.store.enabled ) {
+						implementations = [];
+						sourceModules = [];
+						batch = $.grep( batch, function ( module ) {
+							var implementation = mw.loader.store.get( module );
+							if ( implementation ) {
+								implementations.push( implementation );
+								sourceModules.push( module );
+								return false;
+							}
+							return true;
+						} );
+						asyncEval( implementations, function ( err ) {
+							var failed;
+							// Not good, the cached mw.loader.implement calls failed! This should
+							// never happen, barring ResourceLoader bugs, browser bugs and PEBKACs.
+							// Depending on how corrupt the string is, it is likely that some
+							// modules' implement() succeeded while the ones after the error will
+							// never run and leave their modules in the 'loading' state forever.
+							mw.loader.store.stats.failed++;
+
+							// Since this is an error not caused by an individual module but by
+							// something that infected the implement call itself, don't take any
+							// risks and clear everything in this cache.
+							mw.loader.store.clear();
+
+							mw.track( 'resourceloader.exception', { exception: err, source: 'store-eval' } );
+							// Re-add the failed ones that are still pending back to the batch
+							failed = $.grep( sourceModules, function ( module ) {
+								return registry[ module ].state === 'loading';
+							} );
+							batchRequest( failed );
+						} );
+					}
+
+					batchRequest( batch );
+				},
+
+				/**
+				 * Register a source.
+				 *
+				 * The #work() method will use this information to split up requests by source.
+				 *
+				 *     mw.loader.addSource( 'mediawikiwiki', '//www.mediawiki.org/w/load.php' );
+				 *
+				 * @param {string|Object} id Source ID, or object mapping ids to load urls
+				 * @param {string} loadUrl Url to a load.php end point
+				 * @throws {Error} If source id is already registered
+				 */
+				addSource: function ( id, loadUrl ) {
+					var source;
+					// Allow multiple additions
+					if ( typeof id === 'object' ) {
+						for ( source in id ) {
+							mw.loader.addSource( source, id[ source ] );
+						}
+						return;
+					}
+
+					if ( hasOwn.call( sources, id ) ) {
+						throw new Error( 'source already registered: ' + id );
+					}
+
+					sources[ id ] = loadUrl;
+				},
+
+				/**
+				 * Register a module, letting the system know about it and its properties.
+				 *
+				 * The startup modules contain calls to this method.
+				 *
+				 * When using multiple module registration by passing an array, dependencies that
+				 * are specified as references to modules within the array will be resolved before
+				 * the modules are registered.
+				 *
+				 * @param {string|Array} module Module name or array of arrays, each containing
+				 *  a list of arguments compatible with this method
+				 * @param {string|number} version Module version hash (falls backs to empty string)
+				 *  Can also be a number (timestamp) for compatibility with MediaWiki 1.25 and earlier.
+				 * @param {string|Array|Function} dependencies One string or array of strings of module
+				 *  names on which this module depends, or a function that returns that array.
+				 * @param {string} [group=null] Group which the module is in
+				 * @param {string} [source='local'] Name of the source
+				 * @param {string} [skip=null] Script body of the skip function
+				 */
+				register: function ( module, version, dependencies, group, source, skip ) {
+					var i, deps;
+					// Allow multiple registration
+					if ( typeof module === 'object' ) {
+						resolveIndexedDependencies( module );
+						for ( i = 0; i < module.length; i++ ) {
+							// module is an array of module names
+							if ( typeof module[ i ] === 'string' ) {
+								mw.loader.register( module[ i ] );
+							// module is an array of arrays
+							} else if ( typeof module[ i ] === 'object' ) {
+								mw.loader.register.apply( mw.loader, module[ i ] );
+							}
+						}
+						return;
+					}
+					if ( hasOwn.call( registry, module ) ) {
+						throw new Error( 'module already registered: ' + module );
+					}
+					if ( typeof dependencies === 'string' ) {
+						// A single module name
+						deps = [ dependencies ];
+					} else if ( typeof dependencies === 'object' || typeof dependencies === 'function' ) {
+						// Array of module names or a function that returns an array
+						deps = dependencies;
+					}
+					// List the module as registered
+					registry[ module ] = {
+						// Exposed to execute() for mw.loader.implement() closures.
+						// Import happens via require().
+						module: {
+							exports: {}
+						},
+						version: version !== undefined ? String( version ) : '',
+						dependencies: deps || [],
+						group: typeof group === 'string' ? group : null,
+						source: typeof source === 'string' ? source : 'local',
+						state: 'registered',
+						skip: typeof skip === 'string' ? skip : null
+					};
+				},
+
+				/**
+				 * Implement a module given the components that make up the module.
+				 *
+				 * When #load() or #using() requests one or more modules, the server
+				 * response contain calls to this function.
+				 *
+				 * @param {string} module Name of module and current module version. Formatted
+				 *  as '`[name]@[version]`". This version should match the requested version
+				 *  (from #batchRequest and #registry). This avoids race conditions (T117587).
+				 *  For back-compat with MediaWiki 1.27 and earlier, the version may be omitted.
+				 * @param {Function|Array|string} [script] Function with module code, list of URLs
+				 *  to load via `<script src>`, or string of module code for `$.globalEval()`.
+				 * @param {Object} [style] Should follow one of the following patterns:
+				 *
+				 *     { "css": [css, ..] }
+				 *     { "url": { <media>: [url, ..] } }
+				 *
+				 * And for backwards compatibility (needs to be supported forever due to caching):
+				 *
+				 *     { <media>: css }
+				 *     { <media>: [url, ..] }
+				 *
+				 * The reason css strings are not concatenated anymore is T33676. We now check
+				 * whether it's safe to extend the stylesheet.
+				 *
+				 * @protected
+				 * @param {Object} [messages] List of key/value pairs to be added to mw#messages.
+				 * @param {Object} [templates] List of key/value pairs to be added to mw#templates.
+				 */
+				implement: function ( module, script, style, messages, templates ) {
+					var split = splitModuleKey( module ),
+						name = split.name,
+						version = split.version;
+					// Automatically register module
+					if ( !hasOwn.call( registry, name ) ) {
+						mw.loader.register( name );
+					}
+					// Check for duplicate implementation
+					if ( hasOwn.call( registry, name ) && registry[ name ].script !== undefined ) {
+						throw new Error( 'module already implemented: ' + name );
+					}
+					if ( version ) {
+						// Without this reset, if there is a version mismatch between the
+						// requested and received module version, then mw.loader.store would
+						// cache the response under the requested key. Thus poisoning the cache
+						// indefinitely with a stale value. (T117587)
+						registry[ name ].version = version;
+					}
+					// Attach components
+					registry[ name ].script = script || null;
+					registry[ name ].style = style || null;
+					registry[ name ].messages = messages || null;
+					registry[ name ].templates = templates || null;
+					// The module may already have been marked as erroneous
+					if ( $.inArray( registry[ name ].state, [ 'error', 'missing' ] ) === -1 ) {
+						registry[ name ].state = 'loaded';
+						if ( allReady( registry[ name ].dependencies ) ) {
+							execute( name );
+						}
+					}
+				},
+
+				/**
+				 * Execute a function as soon as one or more required modules are ready.
+				 *
+				 * Example of inline dependency on OOjs:
+				 *
+				 *     mw.loader.using( 'oojs', function () {
+				 *         OO.compare( [ 1 ], [ 1 ] );
+				 *     } );
+				 *
+				 * Since MediaWiki 1.23 this also returns a promise.
+				 *
+				 * Since MediaWiki 1.28 the promise is resolved with a `require` function.
+				 *
+				 * @param {string|Array} dependencies Module name or array of modules names the
+				 *  callback depends on to be ready before executing
+				 * @param {Function} [ready] Callback to execute when all dependencies are ready
+				 * @param {Function} [error] Callback to execute if one or more dependencies failed
+				 * @return {jQuery.Promise} With a `require` function
+				 */
+				using: function ( dependencies, ready, error ) {
+					var deferred = $.Deferred();
+
+					// Allow calling with a single dependency as a string
+					if ( typeof dependencies === 'string' ) {
+						dependencies = [ dependencies ];
+					}
+
+					if ( ready ) {
+						deferred.done( ready );
+					}
+					if ( error ) {
+						deferred.fail( error );
+					}
+
+					try {
+						// Resolve entire dependency map
+						dependencies = resolve( dependencies );
+					} catch ( e ) {
+						return deferred.reject( e ).promise();
+					}
+					if ( allReady( dependencies ) ) {
+						// Run ready immediately
+						deferred.resolve( mw.loader.require );
+					} else if ( anyFailed( dependencies ) ) {
+						// Execute error immediately if any dependencies have errors
+						deferred.reject(
+							new Error( 'One or more dependencies failed to load' ),
+							dependencies
+						);
+					} else {
+						// Not all dependencies are ready, add to the load queue
+						enqueue( dependencies, function () {
+							deferred.resolve( mw.loader.require );
+						}, deferred.reject );
+					}
+
+					return deferred.promise();
+				},
+
+				/**
+				 * Load an external script or one or more modules.
+				 *
+				 * This method takes a list of unrelated modules. Use cases:
+				 *
+				 * - A web page will be composed of many different widgets. These widgets independently
+				 *   queue their ResourceLoader modules (`OutputPage::addModules()`). If any of them
+				 *   have problems, or are no longer known (e.g. cached HTML), the other modules
+				 *   should still be loaded.
+				 * - This method is used for preloading, which must not throw. Later code that
+				 *   calls #using() will handle the error.
+				 *
+				 * @param {string|Array} modules Either the name of a module, array of modules,
+				 *  or a URL of an external script or style
+				 * @param {string} [type='text/javascript'] MIME type to use if calling with a URL of an
+				 *  external script or style; acceptable values are "text/css" and
+				 *  "text/javascript"; if no type is provided, text/javascript is assumed.
+				 */
+				load: function ( modules, type ) {
+					var filtered, l;
+
+					// Allow calling with a url or single dependency as a string
+					if ( typeof modules === 'string' ) {
+						// "https://example.org/x.js", "http://example.org/x.js", "//example.org/x.js", "/x.js"
+						if ( /^(https?:)?\/?\//.test( modules ) ) {
+							if ( type === 'text/css' ) {
+								l = document.createElement( 'link' );
+								l.rel = 'stylesheet';
+								l.href = modules;
+								$( 'head' ).append( l );
+								return;
+							}
+							if ( type === 'text/javascript' || type === undefined ) {
+								addScript( modules );
+								return;
+							}
+							// Unknown type
+							throw new Error( 'invalid type for external url, must be text/css or text/javascript. not ' + type );
+						}
+						// Called with single module
+						modules = [ modules ];
+					}
+
+					// Filter out top-level modules that are unknown or failed to load before.
+					filtered = $.grep( modules, function ( module ) {
+						var state = mw.loader.getState( module );
+						return state !== 'error' && state !== 'missing';
+					} );
+					// Resolve remaining list using the known dependency tree.
+					// This also filters out modules with unknown dependencies. (T36853)
+					filtered = resolveStubbornly( filtered );
+					// If all modules are ready, or if any modules have errors, nothing to be done.
+					if ( allReady( filtered ) || anyFailed( filtered ) ) {
+						return;
+					}
+					if ( filtered.length === 0 ) {
+						return;
+					}
+					// Some modules are not yet ready, add to module load queue.
+					enqueue( filtered, undefined, undefined );
+				},
+
+				/**
+				 * Change the state of one or more modules.
+				 *
+				 * @param {string|Object} module Module name or object of module name/state pairs
+				 * @param {string} state State name
+				 */
+				state: function ( module, state ) {
+					var m;
+
+					if ( typeof module === 'object' ) {
+						for ( m in module ) {
+							mw.loader.state( m, module[ m ] );
+						}
+						return;
+					}
+					if ( !hasOwn.call( registry, module ) ) {
+						mw.loader.register( module );
+					}
+					registry[ module ].state = state;
+					if ( $.inArray( state, [ 'ready', 'error', 'missing' ] ) !== -1 ) {
+						// Make sure pending modules depending on this one get executed if their
+						// dependencies are now fulfilled!
+						handlePending( module );
+					}
+				},
+
+				/**
+				 * Get the version of a module.
+				 *
+				 * @param {string} module Name of module
+				 * @return {string|null} The version, or null if the module (or its version) is not
+				 *  in the registry.
+				 */
+				getVersion: function ( module ) {
+					if ( !hasOwn.call( registry, module ) || registry[ module ].version === undefined ) {
+						return null;
+					}
+					return registry[ module ].version;
+				},
+
+				/**
+				 * Get the state of a module.
+				 *
+				 * @param {string} module Name of module
+				 * @return {string|null} The state, or null if the module (or its state) is not
+				 *  in the registry.
+				 */
+				getState: function ( module ) {
+					if ( !hasOwn.call( registry, module ) || registry[ module ].state === undefined ) {
+						return null;
+					}
+					return registry[ module ].state;
+				},
+
+				/**
+				 * Get the names of all registered modules.
+				 *
+				 * @return {Array}
+				 */
+				getModuleNames: function () {
+					return Object.keys( registry );
+				},
+
+				/**
+				 * Get the exported value of a module.
+				 *
+				 * Modules may provide this via their local `module.exports`.
+				 *
+				 * @protected
+				 * @since 1.27
+				 * @param {string} moduleName Module name
+				 * @return {Mixed} Exported value
+				 */
+				require: function ( moduleName ) {
+					var state = mw.loader.getState( moduleName );
+
+					// Only ready modules can be required
+					if ( state !== 'ready' ) {
+						// Module may've forgotten to declare a dependency
+						throw new Error( 'Module "' + moduleName + '" is not loaded.' );
+					}
+
+					return registry[ moduleName ].module.exports;
+				},
+
+				/**
+				 * @inheritdoc mw.inspect#runReports
+				 * @method
+				 */
+				inspect: function () {
+					var args = slice.call( arguments );
+					mw.loader.using( 'mediawiki.inspect', function () {
+						mw.inspect.runReports.apply( mw.inspect, args );
+					} );
+				},
+
+				/**
+				 * On browsers that implement the localStorage API, the module store serves as a
+				 * smart complement to the browser cache. Unlike the browser cache, the module store
+				 * can slice a concatenated response from ResourceLoader into its constituent
+				 * modules and cache each of them separately, using each module's versioning scheme
+				 * to determine when the cache should be invalidated.
+				 *
+				 * @singleton
+				 * @class mw.loader.store
+				 */
+				store: {
+					// Whether the store is in use on this page.
+					enabled: null,
+
+					// Modules whose string representation exceeds 100 kB are
+					// ineligible for storage. See bug T66721.
+					MODULE_SIZE_MAX: 100 * 1000,
+
+					// The contents of the store, mapping '[name]@[version]' keys
+					// to module implementations.
+					items: {},
+
+					// Cache hit stats
+					stats: { hits: 0, misses: 0, expired: 0, failed: 0 },
+
+					/**
+					 * Construct a JSON-serializable object representing the content of the store.
+					 *
+					 * @return {Object} Module store contents.
+					 */
+					toJSON: function () {
+						return { items: mw.loader.store.items, vary: mw.loader.store.getVary() };
+					},
+
+					/**
+					 * Get the localStorage key for the entire module store. The key references
+					 * $wgDBname to prevent clashes between wikis which share a common host.
+					 *
+					 * @return {string} localStorage item key
+					 */
+					getStoreKey: function () {
+						return 'MediaWikiModuleStore:' + mw.config.get( 'wgDBname' );
+					},
+
+					/**
+					 * Get a key on which to vary the module cache.
+					 *
+					 * @return {string} String of concatenated vary conditions.
+					 */
+					getVary: function () {
+						return [
+							mw.config.get( 'skin' ),
+							mw.config.get( 'wgResourceLoaderStorageVersion' ),
+							mw.config.get( 'wgUserLanguage' )
+						].join( ':' );
+					},
+
+					/**
+					 * Initialize the store.
+					 *
+					 * Retrieves store from localStorage and (if successfully retrieved) decoding
+					 * the stored JSON value to a plain object.
+					 *
+					 * The try / catch block is used for JSON & localStorage feature detection.
+					 * See the in-line documentation for Modernizr's localStorage feature detection
+					 * code for a full account of why we need a try / catch:
+					 * <https://github.com/Modernizr/Modernizr/blob/v2.7.1/modernizr.js#L771-L796>.
+					 */
+					init: function () {
+						var raw, data;
+
+						if ( mw.loader.store.enabled !== null ) {
+							// Init already ran
+							return;
+						}
+
+						if (
+							// Disabled because localStorage quotas are tight and (in Firefox's case)
+							// shared by multiple origins.
+							// See T66721, and <https://bugzilla.mozilla.org/show_bug.cgi?id=1064466>.
+							/Firefox|Opera/.test( navigator.userAgent ) ||
+
+							// Disabled by configuration.
+							!mw.config.get( 'wgResourceLoaderStorageEnabled' )
+						) {
+							// Clear any previous store to free up space. (T66721)
+							mw.loader.store.clear();
+							mw.loader.store.enabled = false;
+							return;
+						}
+						if ( mw.config.get( 'debug' ) ) {
+							// Disable module store in debug mode
+							mw.loader.store.enabled = false;
+							return;
+						}
+
+						try {
+							raw = localStorage.getItem( mw.loader.store.getStoreKey() );
+							// If we get here, localStorage is available; mark enabled
+							mw.loader.store.enabled = true;
+							data = JSON.parse( raw );
+							if ( data && typeof data.items === 'object' && data.vary === mw.loader.store.getVary() ) {
+								mw.loader.store.items = data.items;
+								return;
+							}
+						} catch ( e ) {
+							mw.track( 'resourceloader.exception', { exception: e, source: 'store-localstorage-init' } );
+						}
+
+						if ( raw === undefined ) {
+							// localStorage failed; disable store
+							mw.loader.store.enabled = false;
+						} else {
+							mw.loader.store.update();
+						}
+					},
+
+					/**
+					 * Retrieve a module from the store and update cache hit stats.
+					 *
+					 * @param {string} module Module name
+					 * @return {string|boolean} Module implementation or false if unavailable
+					 */
+					get: function ( module ) {
+						var key;
+
+						if ( !mw.loader.store.enabled ) {
+							return false;
+						}
+
+						key = getModuleKey( module );
+						if ( key in mw.loader.store.items ) {
+							mw.loader.store.stats.hits++;
+							return mw.loader.store.items[ key ];
+						}
+						mw.loader.store.stats.misses++;
+						return false;
+					},
+
+					/**
+					 * Stringify a module and queue it for storage.
+					 *
+					 * @param {string} module Module name
+					 * @param {Object} descriptor The module's descriptor as set in the registry
+					 * @return {boolean} Module was set
+					 */
+					set: function ( module, descriptor ) {
+						var args, key, src;
+
+						if ( !mw.loader.store.enabled ) {
+							return false;
+						}
+
+						key = getModuleKey( module );
+
+						if (
+							// Already stored a copy of this exact version
+							key in mw.loader.store.items ||
+							// Module failed to load
+							descriptor.state !== 'ready' ||
+							// Unversioned, private, or site-/user-specific
+							( !descriptor.version || $.inArray( descriptor.group, [ 'private', 'user' ] ) !== -1 ) ||
+							// Partial descriptor
+							// (e.g. skipped module, or style module with state=ready)
+							$.inArray( undefined, [ descriptor.script, descriptor.style,
+								descriptor.messages, descriptor.templates ] ) !== -1
+						) {
+							// Decline to store
+							return false;
+						}
+
+						try {
+							args = [
+								JSON.stringify( key ),
+								typeof descriptor.script === 'function' ?
+									String( descriptor.script ) :
+									JSON.stringify( descriptor.script ),
+								JSON.stringify( descriptor.style ),
+								JSON.stringify( descriptor.messages ),
+								JSON.stringify( descriptor.templates )
+							];
+							// Attempted workaround for a possible Opera bug (bug T59567).
+							// This regex should never match under sane conditions.
+							if ( /^\s*\(/.test( args[ 1 ] ) ) {
+								args[ 1 ] = 'function' + args[ 1 ];
+								mw.track( 'resourceloader.assert', { source: 'bug-T59567' } );
+							}
+						} catch ( e ) {
+							mw.track( 'resourceloader.exception', { exception: e, source: 'store-localstorage-json' } );
+							return false;
+						}
+
+						src = 'mw.loader.implement(' + args.join( ',' ) + ');';
+						if ( src.length > mw.loader.store.MODULE_SIZE_MAX ) {
+							return false;
+						}
+						mw.loader.store.items[ key ] = src;
+						mw.loader.store.update();
+						return true;
+					},
+
+					/**
+					 * Iterate through the module store, removing any item that does not correspond
+					 * (in name and version) to an item in the module registry.
+					 *
+					 * @return {boolean} Store was pruned
+					 */
+					prune: function () {
+						var key, module;
+
+						if ( !mw.loader.store.enabled ) {
+							return false;
+						}
+
+						for ( key in mw.loader.store.items ) {
+							module = key.slice( 0, key.indexOf( '@' ) );
+							if ( getModuleKey( module ) !== key ) {
+								mw.loader.store.stats.expired++;
+								delete mw.loader.store.items[ key ];
+							} else if ( mw.loader.store.items[ key ].length > mw.loader.store.MODULE_SIZE_MAX ) {
+								// This value predates the enforcement of a size limit on cached modules.
+								delete mw.loader.store.items[ key ];
+							}
+						}
+						return true;
+					},
+
+					/**
+					 * Clear the entire module store right now.
+					 */
+					clear: function () {
+						mw.loader.store.items = {};
+						try {
+							localStorage.removeItem( mw.loader.store.getStoreKey() );
+						} catch ( ignored ) {}
+					},
+
+					/**
+					 * Sync in-memory store back to localStorage.
+					 *
+					 * This function debounces updates. When called with a flush already pending,
+					 * the call is coalesced into the pending update. The call to
+					 * localStorage.setItem will be naturally deferred until the page is quiescent.
+					 *
+					 * Because localStorage is shared by all pages from the same origin, if multiple
+					 * pages are loaded with different module sets, the possibility exists that
+					 * modules saved by one page will be clobbered by another. But the impact would
+					 * be minor and the problem would be corrected by subsequent page views.
+					 *
+					 * @method
+					 */
+					update: ( function () {
+						var hasPendingWrite = false;
+
+						function flushWrites() {
+							var data, key;
+							if ( !hasPendingWrite || !mw.loader.store.enabled ) {
+								return;
+							}
+
+							mw.loader.store.prune();
+							key = mw.loader.store.getStoreKey();
+							try {
+								// Replacing the content of the module store might fail if the new
+								// contents would exceed the browser's localStorage size limit. To
+								// avoid clogging the browser with stale data, always remove the old
+								// value before attempting to set the new one.
+								localStorage.removeItem( key );
+								data = JSON.stringify( mw.loader.store );
+								localStorage.setItem( key, data );
+							} catch ( e ) {
+								mw.track( 'resourceloader.exception', { exception: e, source: 'store-localstorage-update' } );
+							}
+
+							hasPendingWrite = false;
+						}
+
+						return function () {
+							if ( !hasPendingWrite ) {
+								hasPendingWrite = true;
+								mw.requestIdleCallback( flushWrites );
+							}
+						};
+					}() )
+				}
+			};
+		}() ),
+
+		/**
+		 * HTML construction helper functions
+		 *
+		 *     @example
+		 *
+		 *     var Html, output;
+		 *
+		 *     Html = mw.html;
+		 *     output = Html.element( 'div', {}, new Html.Raw(
+		 *         Html.element( 'img', { src: '<' } )
+		 *     ) );
+		 *     mw.log( output ); // <div><img src="&lt;"/></div>
+		 *
+		 * @class mw.html
+		 * @singleton
+		 */
+		html: ( function () {
+			function escapeCallback( s ) {
+				switch ( s ) {
+					case '\'':
+						return '&#039;';
+					case '"':
+						return '&quot;';
+					case '<':
+						return '&lt;';
+					case '>':
+						return '&gt;';
+					case '&':
+						return '&amp;';
+				}
+			}
+
+			return {
+				/**
+				 * Escape a string for HTML.
+				 *
+				 * Converts special characters to HTML entities.
+				 *
+				 *     mw.html.escape( '< > \' & "' );
+				 *     // Returns &lt; &gt; &#039; &amp; &quot;
+				 *
+				 * @param {string} s The string to escape
+				 * @return {string} HTML
+				 */
+				escape: function ( s ) {
+					return s.replace( /['"<>&]/g, escapeCallback );
+				},
+
+				/**
+				 * Create an HTML element string, with safe escaping.
+				 *
+				 * @param {string} name The tag name.
+				 * @param {Object} [attrs] An object with members mapping element names to values
+				 * @param {string|mw.html.Raw|mw.html.Cdata|null} [contents=null] The contents of the element.
+				 *
+				 *  - string: Text to be escaped.
+				 *  - null: The element is treated as void with short closing form, e.g. `<br/>`.
+				 *  - this.Raw: The raw value is directly included.
+				 *  - this.Cdata: The raw value is directly included. An exception is
+				 *    thrown if it contains any illegal ETAGO delimiter.
+				 *    See <https://www.w3.org/TR/html401/appendix/notes.html#h-B.3.2>.
+				 * @return {string} HTML
+				 */
+				element: function ( name, attrs, contents ) {
+					var v, attrName, s = '<' + name;
+
+					if ( attrs ) {
+						for ( attrName in attrs ) {
+							v = attrs[ attrName ];
+							// Convert name=true, to name=name
+							if ( v === true ) {
+								v = attrName;
+							// Skip name=false
+							} else if ( v === false ) {
+								continue;
+							}
+							s += ' ' + attrName + '="' + this.escape( String( v ) ) + '"';
+						}
+					}
+					if ( contents === undefined || contents === null ) {
+						// Self close tag
+						s += '/>';
+						return s;
+					}
+					// Regular open tag
+					s += '>';
+					switch ( typeof contents ) {
+						case 'string':
+							// Escaped
+							s += this.escape( contents );
+							break;
+						case 'number':
+						case 'boolean':
+							// Convert to string
+							s += String( contents );
+							break;
+						default:
+							if ( contents instanceof this.Raw ) {
+								// Raw HTML inclusion
+								s += contents.value;
+							} else if ( contents instanceof this.Cdata ) {
+								// CDATA
+								if ( /<\/[a-zA-z]/.test( contents.value ) ) {
+									throw new Error( 'mw.html.element: Illegal end tag found in CDATA' );
+								}
+								s += contents.value;
+							} else {
+								throw new Error( 'mw.html.element: Invalid type of contents' );
+							}
+					}
+					s += '</' + name + '>';
+					return s;
+				},
+
+				/**
+				 * Wrapper object for raw HTML passed to mw.html.element().
+				 *
+				 * @class mw.html.Raw
+				 * @constructor
+				 * @param {string} value
+				 */
+				Raw: function ( value ) {
+					this.value = value;
+				},
+
+				/**
+				 * Wrapper object for CDATA element contents passed to mw.html.element()
+				 *
+				 * @class mw.html.Cdata
+				 * @constructor
+				 * @param {string} value
+				 */
+				Cdata: function ( value ) {
+					this.value = value;
+				}
+			};
+		}() ),
+
+		// Skeleton user object, extended by the 'mediawiki.user' module.
+		/**
+		 * @class mw.user
+		 * @singleton
+		 */
+		user: {
+			/**
+			 * @property {mw.Map}
+			 */
+			options: new Map(),
+			/**
+			 * @property {mw.Map}
+			 */
+			tokens: new Map()
+		},
+
+		// OOUI widgets specific to MediaWiki
+		widgets: {},
+
+		/**
+		 * Registry and firing of events.
+		 *
+		 * MediaWiki has various interface components that are extended, enhanced
+		 * or manipulated in some other way by extensions, gadgets and even
+		 * in core itself.
+		 *
+		 * This framework helps streamlining the timing of when these other
+		 * code paths fire their plugins (instead of using document-ready,
+		 * which can and should be limited to firing only once).
+		 *
+		 * Features like navigating to other wiki pages, previewing an edit
+		 * and editing itself – without a refresh – can then retrigger these
+		 * hooks accordingly to ensure everything still works as expected.
+		 *
+		 * Example usage:
+		 *
+		 *     mw.hook( 'wikipage.content' ).add( fn ).remove( fn );
+		 *     mw.hook( 'wikipage.content' ).fire( $content );
+		 *
+		 * Handlers can be added and fired for arbitrary event names at any time. The same
+		 * event can be fired multiple times. The last run of an event is memorized
+		 * (similar to `$(document).ready` and `$.Deferred().done`).
+		 * This means if an event is fired, and a handler added afterwards, the added
+		 * function will be fired right away with the last given event data.
+		 *
+		 * Like Deferreds and Promises, the mw.hook object is both detachable and chainable.
+		 * Thus allowing flexible use and optimal maintainability and authority control.
+		 * You can pass around the `add` and/or `fire` method to another piece of code
+		 * without it having to know the event name (or `mw.hook` for that matter).
+		 *
+		 *     var h = mw.hook( 'bar.ready' );
+		 *     new mw.Foo( .. ).fetch( { callback: h.fire } );
+		 *
+		 * Note: Events are documented with an underscore instead of a dot in the event
+		 * name due to jsduck not supporting dots in that position.
+		 *
+		 * @class mw.hook
+		 */
+		hook: ( function () {
+			var lists = {};
+
+			/**
+			 * Create an instance of mw.hook.
+			 *
+			 * @method hook
+			 * @member mw
+			 * @param {string} name Name of hook.
+			 * @return {mw.hook}
+			 */
+			return function ( name ) {
+				var list = hasOwn.call( lists, name ) ?
+					lists[ name ] :
+					lists[ name ] = $.Callbacks( 'memory' );
+
+				return {
+					/**
+					 * Register a hook handler
+					 *
+					 * @param {...Function} handler Function to bind.
+					 * @chainable
+					 */
+					add: list.add,
+
+					/**
+					 * Unregister a hook handler
+					 *
+					 * @param {...Function} handler Function to unbind.
+					 * @chainable
+					 */
+					remove: list.remove,
+
+					// eslint-disable-next-line valid-jsdoc
+					/**
+					 * Run a hook.
+					 *
+					 * @param {...Mixed} data
+					 * @chainable
+					 */
+					fire: function () {
+						return list.fireWith.call( this, null, slice.call( arguments ) );
+					}
+				};
+			};
+		}() )
+	};
+
+	// Alias $j to jQuery for backwards compatibility
+	// @deprecated since 1.23 Use $ or jQuery instead
+	mw.log.deprecate( window, '$j', $, 'Use $ or jQuery instead.' );
+
+	/**
+	 * Log a message to window.console, if possible.
+	 *
+	 * Useful to force logging of some errors that are otherwise hard to detect (i.e., this logs
+	 * also in production mode). Gets console references in each invocation instead of caching the
+	 * reference, so that debugging tools loaded later are supported (e.g. Firebug Lite in IE).
+	 *
+	 * @private
+	 * @param {string} topic Stream name passed by mw.track
+	 * @param {Object} data Data passed by mw.track
+	 * @param {Error} [data.exception]
+	 * @param {string} data.source Error source
+	 * @param {string} [data.module] Name of module which caused the error
+	 */
+	function logError( topic, data ) {
+		/* eslint-disable no-console */
+		var msg,
+			e = data.exception,
+			source = data.source,
+			module = data.module,
+			console = window.console;
+
+		if ( console && console.log ) {
+			msg = ( e ? 'Exception' : 'Error' ) + ' in ' + source;
+			if ( module ) {
+				msg += ' in module ' + module;
+			}
+			msg += ( e ? ':' : '.' );
+			console.log( msg );
+
+			// If we have an exception object, log it to the warning channel to trigger
+			// proper stacktraces in browsers that support it.
+			if ( e && console.warn ) {
+				console.warn( String( e ), e );
+			}
+		}
+		/* eslint-enable no-console */
+	}
+
+	// Subscribe to error streams
+	mw.trackSubscribe( 'resourceloader.exception', logError );
+	mw.trackSubscribe( 'resourceloader.assert', logError );
+
+	/**
+	 * Fired when all modules associated with the page have finished loading.
+	 *
+	 * @event resourceloader_loadEnd
+	 * @member mw.hook
+	 */
+	$( function () {
+		var loading, modules;
+
+		modules = $.grep( mw.loader.getModuleNames(), function ( module ) {
+			return mw.loader.getState( module ) === 'loading';
+		} );
+		// We only need a callback, not any actual module. First try a single using()
+		// for all loading modules. If one fails, fall back to tracking each module
+		// separately via $.when(), this is expensive.
+		loading = mw.loader.using( modules ).then( null, function () {
+			var all = modules.map( function ( module ) {
+				return mw.loader.using( module ).then( null, function () {
+					return $.Deferred().resolve();
+				} );
+			} );
+			return $.when.apply( $, all );
+		} );
+		loading.then( function () {
+			/* global mwPerformance */
+			mwPerformance.mark( 'mwLoadEnd' );
+			mw.hook( 'resourceloader.loadEnd' ).fire();
+		} );
+	} );
+
+	// Attach to window and globally alias
+	window.mw = window.mediaWiki = mw;
+}( jQuery ) );