mediawiki-extensions-Visual.../modules/oojs/oo.js

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/*!
* Object Oriented JavaScript Library v1.0.2
* https://github.com/trevorparscal/oojs
*
* Copyright 2011-2013 OOJS Team and other contributors.
* Released under the MIT license
* http://oojs.mit-license.org
*
* Date: Thu Jul 25 04:28:57 2013 GMT+0200 (CEST)
*/
( function ( global ) {
'use strict';
var
/**
* Namespace for all classes, static methods and static properties.
* @class OO
* @singleton
*/
oo = {},
hasOwn = oo.hasOwnProperty,
toString = oo.toString;
/* Class Methods */
/**
* Assert whether a value is a plain object or not.
*
* @method
* @param {Mixed} obj
* @return {boolean}
*/
oo.isPlainObject = function ( obj ) {
// Any object or value whose internal [[Class]] property is not "[object Object]"
if ( toString.call( obj ) !== '[object Object]' ) {
return false;
}
// The try/catch suppresses exceptions thrown when attempting to access
// the "constructor" property of certain host objects suich as window.location
// in Firefox < 20 (https://bugzilla.mozilla.org/814622)
try {
if ( obj.constructor &&
!hasOwn.call( obj.constructor.prototype, 'isPrototypeOf' ) ) {
return false;
}
} catch ( e ) {
return false;
}
return true;
};
/**
* Utility for common usage of Object#create for inheriting from one
* prototype to another.
*
* Beware: This redefines the prototype, call before setting your prototypes.
* Beware: This redefines the prototype, can only be called once on a function.
* If called multiple times on the same function, the previous prototype is lost.
* This is how prototypal inheritance works, it can only be one straight chain
* (just like classical inheritance in PHP for example). If you need to work with
* multiple constructors consider storing an instance of the other constructor in a
* property instead, or perhaps use a mixin (see oo.mixinClass).
*
* function Foo() {}
* Foo.prototype.jump = function () {};
*
* function FooBar() {}
* oo.inheritClass( FooBar, Foo );
* FooBar.prop.feet = 2;
* FooBar.prototype.walk = function () {};
*
* function FooBarQuux() {}
* OO.inheritClass( FooBarQuux, FooBar );
* FooBarQuux.prototype.jump = function () {};
*
* FooBarQuux.prop.feet === 2;
* var fb = new FooBar();
* fb.jump();
* fb.walk();
* fb instanceof Foo && fb instanceof FooBar && fb instanceof FooBarQuux;
*
* @method
* @param {Function} targetFn
* @param {Function} originFn
* @throws {Error} If target already inherits from origin
*/
oo.inheritClass = function ( targetFn, originFn ) {
if ( targetFn.prototype instanceof originFn ) {
throw new Error( 'Target already inherits from origin' );
}
var targetConstructor = targetFn.prototype.constructor;
targetFn.prototype = Object.create( originFn.prototype, {
// Restore constructor property of targetFn
constructor: {
value: targetConstructor,
enumerable: false,
writable: true,
configurable: true
}
} );
// Extend static properties - always initialize both sides
originFn.static = originFn.static || {};
targetFn.static = Object.create( originFn.static );
// Copy mixin tracking
targetFn.mixins = originFn.mixins ? originFn.mixins.slice( 0 ) : [];
};
/**
* Utility to copy over *own* prototype properties of a mixin.
* The 'constructor' (whether implicit or explicit) is not copied over.
*
* This does not create inheritance to the origin. If inheritance is needed
* use oo.inheritClass instead.
*
* Beware: This can redefine a prototype property, call before setting your prototypes.
* Beware: Don't call before oo.inheritClass.
*
* function Foo() {}
* function Context() {}
*
* // Avoid repeating this code
* function ContextLazyLoad() {}
* ContextLazyLoad.prototype.getContext = function () {
* if ( !this.context ) {
* this.context = new Context();
* }
* return this.context;
* };
*
* function FooBar() {}
* OO.inheritClass( FooBar, Foo );
* OO.mixinClass( FooBar, ContextLazyLoad );
*
* @method
* @param {Function} targetFn
* @param {Function} originFn
*/
oo.mixinClass = function ( targetFn, originFn ) {
var key;
// Copy prototype properties
for ( key in originFn.prototype ) {
if ( key !== 'constructor' && hasOwn.call( originFn.prototype, key ) ) {
targetFn.prototype[key] = originFn.prototype[key];
}
}
// Copy static properties - always initialize both sides
targetFn.static = targetFn.static || {};
if ( originFn.static ) {
for ( key in originFn.static ) {
if ( hasOwn.call( originFn.static, key ) ) {
targetFn.static[key] = originFn.static[key];
}
}
} else {
originFn.static = {};
}
};
/* Object Methods */
/**
* Create a new object that is an instance of the same
* constructor as the input, inherits from the same object
* and contains the same own properties.
*
* This makes a shallow non-recursive copy of own properties.
* To create a recursive copy of plain objects, use #copy.
*
* var foo = new Person( mom, dad );
* foo.setAge( 21 );
* var foo2 = OO.cloneObject( foo );
* foo.setAge( 22 );
*
* // Then
* foo2 !== foo; // true
* foo2 instanceof Person; // true
* foo2.getAge(); // 21
* foo.getAge(); // 22
*
* @method
* @param {Object} origin
* @return {Object} Clone of origin
*/
oo.cloneObject = function ( origin ) {
var key, r;
r = Object.create( origin.constructor.prototype );
for ( key in origin ) {
if ( hasOwn.call( origin, key ) ) {
r[key] = origin[key];
}
}
return r;
};
/**
* Gets an array of all property values in an object.
*
* @method
* @param {Object} Object to get values from
* @returns {Array} List of object values
*/
oo.getObjectValues = function ( obj ) {
var key, values;
if ( obj !== Object( obj ) ) {
throw new TypeError( 'Called on non-object' );
}
values = [];
for ( key in obj ) {
if ( hasOwn.call( obj, key ) ) {
values[values.length] = obj[key];
}
}
return values;
};
/**
* Recursively compares properties between two objects.
*
* A false result may be caused by property inequality or by properties in one object missing from
* the other. An asymmetrical test may also be performed, which checks only that properties in the
* first object are present in the second object, but not the inverse.
*
* @method
* @param {Object} a First object to compare
* @param {Object} b Second object to compare
* @param {boolean} [asymmetrical] Whether to check only that b contains values from a
* @returns {boolean} If the objects contain the same values as each other
*/
oo.compare = function ( a, b, asymmetrical ) {
var aValue, bValue, aType, bType, k;
if ( a === b ) {
return true;
}
for ( k in a ) {
aValue = a[k];
bValue = b[k];
aType = typeof aValue;
bType = typeof bValue;
if ( aType !== bType ||
( ( aType === 'string' || aType === 'number' ) && aValue !== bValue ) ||
( aValue === Object( aValue ) && !oo.compare( aValue, bValue, asymmetrical ) ) ) {
return false;
}
}
// If the check is not asymmetrical, recursing with the arguments swapped will verify our result
return asymmetrical ? true : oo.compare( b, a, true );
};
/**
* Create a plain deep copy of any kind of object.
*
* Copies are deep, and will either be an object or an array depending on `source`.
*
* @method
* @param {Object} source Object to copy
* @param {Function} [callback] Applied to leaf values before they added to the clone
* @returns {Object} Copy of source object
*/
oo.copy = function ( source, callback ) {
var key, sourceValue, sourceType, destination;
if ( typeof source.clone === 'function' ) {
return source.clone();
}
destination = Array.isArray( source ) ? new Array( source.length ) : {};
for ( key in source ) {
sourceValue = source[key];
sourceType = typeof sourceValue;
if ( Array.isArray( sourceValue ) ) {
// Array
destination[key] = oo.copy( sourceValue, callback );
} else if ( sourceValue && typeof sourceValue.clone === 'function' ) {
// Duck type object with custom clone method
destination[key] = callback ?
callback( sourceValue.clone() ) : sourceValue.clone();
} else if ( sourceValue && typeof sourceValue.cloneNode === 'function' ) {
// DOM Node
destination[key] = callback ?
callback( sourceValue.cloneNode( true ) ) : sourceValue.cloneNode( true );
} else if ( oo.isPlainObject( sourceValue ) ) {
// Plain objects
destination[key] = oo.copy( sourceValue, callback );
} else {
// Non-plain objects (incl. functions) and primitive values
destination[key] = callback ? callback( sourceValue ) : sourceValue;
}
}
return destination;
};
/**
* Event emitter.
*
* @class OO.EventEmitter
* @constructor
* @property {Object} bindings
*/
oo.EventEmitter = function OoEventEmitter() {
// Properties
this.bindings = {};
};
/* Methods */
/**
* Add a listener to events of a specific event.
*
* @method
* @param {string} event Type of event to listen to
* @param {Function} callback Function to call when event occurs
* @param {Array} [args] Arguments to pass to listener, will be prepended to emitted arguments
* @param {Object} [context=null] Object to use as context for callback function or call method on
* @throws {Error} Listener argument is not a function or method name
* @chainable
*/
oo.EventEmitter.prototype.on = function ( event, callback, args, context ) {
// Validate callback
if ( typeof callback !== 'function' ) {
throw new Error( 'Invalid callback. Function or method name expected.' );
}
// Auto-initialize binding
if ( !( event in this.bindings ) ) {
this.bindings[event] = [];
}
// Add binding
this.bindings[event].push( {
'callback': callback,
'args': args,
'context': context || null
} );
return this;
};
/**
* Adds a one-time listener to a specific event.
*
* @method
* @param {string} event Type of event to listen to
* @param {Function} listener Listener to call when event occurs
* @chainable
*/
oo.EventEmitter.prototype.once = function ( event, listener ) {
var eventEmitter = this;
return this.on( event, function listenerWrapper() {
eventEmitter.off( event, listenerWrapper );
listener.apply( eventEmitter, Array.prototype.slice.call( arguments, 0 ) );
} );
};
/**
* Remove a specific listener from a specific event.
*
* @method
* @param {string} event Type of event to remove listener from
* @param {Function} [callback] Listener to remove, omit to remove all
* @chainable
* @throws {Error} Listener argument is not a function
*/
oo.EventEmitter.prototype.off = function ( event, callback ) {
var i, bindings;
if ( arguments.length === 1 ) {
// Remove all bindings for event
if ( event in this.bindings ) {
delete this.bindings[event];
}
} else {
if ( typeof callback !== 'function' ) {
throw new Error( 'Invalid callback. Function expected.' );
}
if ( !( event in this.bindings ) || !this.bindings[event].length ) {
// No matching bindings
return this;
}
// Remove matching handlers
bindings = this.bindings[event];
i = bindings.length;
while ( i-- ) {
if ( bindings[i].callback === callback ) {
bindings.splice( i, 1 );
}
}
// Cleanup if now empty
if ( bindings.length === 0 ) {
delete this.bindings[event];
}
}
return this;
};
/**
* Emit an event.
* TODO: Should this be chainable? What is the usefulness of the boolean
* return value here?
*
* @method
* @param {string} event Type of event
* @param {Mixed} args First in a list of variadic arguments passed to event handler (optional)
* @returns {boolean} If event was handled by at least one listener
*/
oo.EventEmitter.prototype.emit = function ( event ) {
var i, len, binding, bindings, args;
if ( event in this.bindings ) {
// Slicing ensures that we don't get tripped up by event handlers that add/remove bindings
bindings = this.bindings[event].slice();
args = Array.prototype.slice.call( arguments, 1 );
for ( i = 0, len = bindings.length; i < len; i++ ) {
binding = bindings[i];
binding.callback.apply(
binding.context,
binding.args ? binding.args.concat( args ) : args
);
}
return true;
}
return false;
};
/**
* Connect event handlers to an object.
*
* @method
* @param {Object} context Object to call methods on when events occur
* @param {Object.<string,string>|Object.<string,Function>|Object.<string,Array>} methods List of
* event bindings keyed by event name containing either method names, functions or arrays containing
* method name or function followed by a list of arguments to be passed to callback before emitted
* arguments
* @chainable
*/
oo.EventEmitter.prototype.connect = function ( context, methods ) {
var method, callback, args, event;
for ( event in methods ) {
method = methods[event];
// Allow providing additional args
if ( Array.isArray( method ) ) {
args = method.slice( 1 );
method = method[0];
} else {
args = [];
}
// Allow callback to be a method name
if ( typeof method === 'string' ) {
// Validate method
if ( !context[method] || typeof context[method] !== 'function' ) {
throw new Error( 'Method not found: ' + method );
}
// Resolve to function
callback = context[method];
} else {
callback = method;
}
// Add binding
this.on.apply( this, [ event, callback, args, context ] );
}
return this;
};
/**
* Disconnect event handlers from an object.
*
* @method
* @param {Object} context Object to disconnect methods from
* @param {Object.<string,string>|Object.<string,Function>|Object.<string,Array>} [methods] List of
* event bindings keyed by event name containing either method names or functions
* @chainable
*/
oo.EventEmitter.prototype.disconnect = function ( context, methods ) {
var i, method, callback, event, bindings;
if ( methods ) {
for ( event in methods ) {
method = methods[event];
if ( typeof method === 'string' ) {
// Validate method
if ( !context[method] || typeof context[method] !== 'function' ) {
throw new Error( 'Method not found: ' + method );
}
// Resolve to function
callback = context[method];
} else {
callback = method;
}
bindings = this.bindings[event];
i = bindings.length;
while ( i-- ) {
if ( bindings[i].context === context && bindings[i].callback === callback ) {
bindings.splice( i, 1 );
}
}
if ( bindings.length === 0 ) {
delete this.bindings[event];
}
}
} else {
for ( event in this.bindings ) {
bindings = this.bindings[event];
i = bindings.length;
while ( i-- ) {
if ( bindings[i].context === context ) {
bindings.splice( i, 1 );
}
}
if ( bindings.length === 0 ) {
delete this.bindings[event];
}
}
}
return this;
};
/*jshint node:true */
if ( typeof module !== 'undefined' && module.exports ) {
module.exports = oo;
} else {
global.OO = oo;
}
}( this ) );