/**
* Supplies object inheritance and manipulation utilities. This adds
* additional functionaity to what is provided in yui-base, and the
* methods are applied directly to the YUI instance. This module
* is required for most YUI components.
* @module oop
*/
/**
* The following methods are added to the YUI instance
* @class YUI~oop
*/
var L = Y.Lang,
A = Y.Array,
OP = Object.prototype,
CLONE_MARKER = '_~yuim~_',
EACH = 'each',
SOME = 'some',
dispatch = function(o, f, c, proto, action) {
if (o && o[action] && o !== Y) {
return o[action].call(o, f, c);
} else {
switch (A.test(o)) {
case 1:
return A[action](o, f, c);
case 2:
return A[action](Y.Array(o, 0, true), f, c);
default:
return Y.Object[action](o, f, c, proto);
}
}
};
/**
* Applies prototype properties from the supplier to the receiver.
* The receiver can be a constructor or an instance.
* @method augment
* @param {function} r the object to receive the augmentation.
* @param {function} s the object that supplies the properties to augment.
* @param {boolean} ov if true, properties already on the receiver
* will be overwritten if found on the supplier.
* @param {string[]} wl a whitelist. If supplied, only properties in
* this list will be applied to the receiver.
* @param {Array | Any} args arg or arguments to apply to the supplier
* constructor when initializing.
* @return {object} the augmented object.
*
* @todo constructor optional?
* @todo understanding what an instance is augmented with
* @todo best practices for overriding sequestered methods.
*/
Y.augment = function(r, s, ov, wl, args) {
var sProto = s.prototype,
newProto = null,
construct = s,
a = (args) ? Y.Array(args) : [],
rProto = r.prototype,
target = rProto || r,
applyConstructor = false,
sequestered, replacements;
// working on a class, so apply constructor infrastructure
if (rProto && construct) {
sequestered = {};
replacements = {};
newProto = {};
// sequester all of the functions in the supplier and replace with
// one that will restore all of them.
Y.Object.each(sProto, function(v, k) {
replacements[k] = function() {
// Y.log('sequestered function "' + k +
// '" executed. Initializing EventTarget');
// overwrite the prototype with all of the sequestered functions,
// but only if it hasn't been overridden
for (var i in sequestered) {
if (sequestered.hasOwnProperty(i) &&
(this[i] === replacements[i])) {
// Y.log('... restoring ' + k);
this[i] = sequestered[i];
}
}
// apply the constructor
construct.apply(this, a);
// apply the original sequestered function
return sequestered[k].apply(this, arguments);
};
if ((!wl || (k in wl)) && (ov || !(k in this))) {
// Y.log('augment: ' + k);
if (L.isFunction(v)) {
// sequester the function
sequestered[k] = v;
// replace the sequestered function with a function that will
// restore all sequestered functions and exectue the constructor.
this[k] = replacements[k];
} else {
// Y.log('augment() applying non-function: ' + k);
this[k] = v;
}
}
}, newProto, true);
// augmenting an instance, so apply the constructor immediately
} else {
applyConstructor = true;
}
Y.mix(target, newProto || sProto, ov, wl);
if (applyConstructor) {
s.apply(target, a);
}
return r;
};
/**
* Applies object properties from the supplier to the receiver. If
* the target has the property, and the property is an object, the target
* object will be augmented with the supplier's value. If the property
* is an array, the suppliers value will be appended to the target.
* @method aggregate
* @param {function} r the object to receive the augmentation.
* @param {function} s the object that supplies the properties to augment.
* @param {boolean} ov if true, properties already on the receiver
* will be overwritten if found on the supplier.
* @param {string[]} wl a whitelist. If supplied, only properties in
* this list will be applied to the receiver.
* @return {object} the extended object.
*/
Y.aggregate = function(r, s, ov, wl) {
return Y.mix(r, s, ov, wl, 0, true);
};
/**
* Utility to set up the prototype, constructor and superclass properties to
* support an inheritance strategy that can chain constructors and methods.
* Static members will not be inherited.
*
* @method extend
* @param {function} r the object to modify.
* @param {function} s the object to inherit.
* @param {object} px prototype properties to add/override.
* @param {object} sx static properties to add/override.
* @return {object} the extended object.
*/
Y.extend = function(r, s, px, sx) {
if (!s || !r) {
Y.error('extend failed, verify dependencies');
}
var sp = s.prototype, rp = Y.Object(sp);
r.prototype = rp;
rp.constructor = r;
r.superclass = sp;
// assign constructor property
if (s != Object && sp.constructor == OP.constructor) {
sp.constructor = s;
}
// add prototype overrides
if (px) {
Y.mix(rp, px, true);
}
// add object overrides
if (sx) {
Y.mix(r, sx, true);
}
return r;
};
/**
* Executes the supplied function for each item in
* a collection. Supports arrays, objects, and
* Y.NodeLists
* @method each
* @param {object} o the object to iterate.
* @param {function} f the function to execute. This function
* receives the value, key, and object as parameters.
* @param {object} c the execution context for the function.
* @param {boolean} proto if true, prototype properties are
* iterated on objects.
* @return {YUI} the YUI instance.
*/
Y.each = function(o, f, c, proto) {
return dispatch(o, f, c, proto, EACH);
};
/**
* Executes the supplied function for each item in
* a collection. The operation stops if the function
* returns true. Supports arrays, objects, and
* Y.NodeLists.
* @method some
* @param {object} o the object to iterate.
* @param {function} f the function to execute. This function
* receives the value, key, and object as parameters.
* @param {object} c the execution context for the function.
* @param {boolean} proto if true, prototype properties are
* iterated on objects.
* @return {boolean} true if the function ever returns true,
* false otherwise.
*/
Y.some = function(o, f, c, proto) {
return dispatch(o, f, c, proto, SOME);
};
/**
* Deep obj/array copy. Function clones are actually
* wrappers around the original function.
* Array-like objects are treated as arrays.
* Primitives are returned untouched. Optionally, a
* function can be provided to handle other data types,
* filter keys, validate values, etc.
*
* @method clone
* @param {object} o what to clone.
* @param {boolean} safe if true, objects will not have prototype
* items from the source. If false, they will. In this case, the
* original is initially protected, but the clone is not completely
* immune from changes to the source object prototype. Also, cloned
* prototype items that are deleted from the clone will result
* in the value of the source prototype being exposed. If operating
* on a non-safe clone, items should be nulled out rather than deleted.
* @param {function} f optional function to apply to each item in a
* collection; it will be executed prior to applying the value to
* the new object. Return false to prevent the copy.
* @param {object} c optional execution context for f.
* @param {object} owner Owner object passed when clone is iterating
* an object. Used to set up context for cloned functions.
* @param {object} cloned hash of previously cloned objects to avoid
* multiple clones.
* @return {Array|Object} the cloned object.
*/
Y.clone = function(o, safe, f, c, owner, cloned) {
if (!L.isObject(o)) {
return o;
}
// @todo cloning YUI instances doesn't currently work
if (Y.instanceOf(o, YUI)) {
return o;
}
var o2, marked = cloned || {}, stamp,
yeach = Y.each;
switch (L.type(o)) {
case 'date':
return new Date(o);
case 'regexp':
// if we do this we need to set the flags too
// return new RegExp(o.source);
return o;
case 'function':
// o2 = Y.bind(o, owner);
// break;
return o;
case 'array':
o2 = [];
break;
default:
// #2528250 only one clone of a given object should be created.
if (o[CLONE_MARKER]) {
return marked[o[CLONE_MARKER]];
}
stamp = Y.guid();
o2 = (safe) ? {} : Y.Object(o);
o[CLONE_MARKER] = stamp;
marked[stamp] = o;
}
// #2528250 don't try to clone element properties
if (!o.addEventListener && !o.attachEvent) {
yeach(o, function(v, k) {
if ((k || k === 0) && (!f || (f.call(c || this, v, k, this, o) !== false))) {
if (k !== CLONE_MARKER) {
if (k == 'prototype') {
// skip the prototype
// } else if (o[k] === o) {
// this[k] = this;
} else {
this[k] =
Y.clone(v, safe, f, c, owner || o, marked);
}
}
}
}, o2);
}
if (!cloned) {
Y.Object.each(marked, function(v, k) {
if (v[CLONE_MARKER]) {
try {
delete v[CLONE_MARKER];
} catch (e) {
v[CLONE_MARKER] = null;
}
}
}, this);
marked = null;
}
return o2;
};
/**
* Returns a function that will execute the supplied function in the
* supplied object's context, optionally adding any additional
* supplied parameters to the beginning of the arguments collection the
* supplied to the function.
*
* @method bind
* @param {Function|String} f the function to bind, or a function name
* to execute on the context object.
* @param {object} c the execution context.
* @param {any} args* 0..n arguments to include before the arguments the
* function is executed with.
* @return {function} the wrapped function.
*/
Y.bind = function(f, c) {
var xargs = arguments.length > 2 ?
Y.Array(arguments, 2, true) : null;
return function() {
var fn = L.isString(f) ? c[f] : f,
args = (xargs) ?
xargs.concat(Y.Array(arguments, 0, true)) : arguments;
return fn.apply(c || fn, args);
};
};
/**
* Returns a function that will execute the supplied function in the
* supplied object's context, optionally adding any additional
* supplied parameters to the end of the arguments the function
* is executed with.
*
* @method rbind
* @param {Function|String} f the function to bind, or a function name
* to execute on the context object.
* @param {object} c the execution context.
* @param {any} args* 0..n arguments to append to the end of
* arguments collection supplied to the function.
* @return {function} the wrapped function.
*/
Y.rbind = function(f, c) {
var xargs = arguments.length > 2 ? Y.Array(arguments, 2, true) : null;
return function() {
var fn = L.isString(f) ? c[f] : f,
args = (xargs) ?
Y.Array(arguments, 0, true).concat(xargs) : arguments;
return fn.apply(c || fn, args);
};
};