| var baseRest = require('./_baseRest'), |
| eq = require('./eq'), |
| isIterateeCall = require('./_isIterateeCall'), |
| keysIn = require('./keysIn'); |
| |
| /** Used for built-in method references. */ |
| var objectProto = Object.prototype; |
| |
| /** Used to check objects for own properties. */ |
| var hasOwnProperty = objectProto.hasOwnProperty; |
| |
| /** |
| * Assigns own and inherited enumerable string keyed properties of source |
| * objects to the destination object for all destination properties that |
| * resolve to `undefined`. Source objects are applied from left to right. |
| * Once a property is set, additional values of the same property are ignored. |
| * |
| * **Note:** This method mutates `object`. |
| * |
| * @static |
| * @since 0.1.0 |
| * @memberOf _ |
| * @category Object |
| * @param {Object} object The destination object. |
| * @param {...Object} [sources] The source objects. |
| * @returns {Object} Returns `object`. |
| * @see _.defaultsDeep |
| * @example |
| * |
| * _.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 }); |
| * // => { 'a': 1, 'b': 2 } |
| */ |
| var defaults = baseRest(function(object, sources) { |
| object = Object(object); |
| |
| var index = -1; |
| var length = sources.length; |
| var guard = length > 2 ? sources[2] : undefined; |
| |
| if (guard && isIterateeCall(sources[0], sources[1], guard)) { |
| length = 1; |
| } |
| |
| while (++index < length) { |
| var source = sources[index]; |
| var props = keysIn(source); |
| var propsIndex = -1; |
| var propsLength = props.length; |
| |
| while (++propsIndex < propsLength) { |
| var key = props[propsIndex]; |
| var value = object[key]; |
| |
| if (value === undefined || |
| (eq(value, objectProto[key]) && !hasOwnProperty.call(object, key))) { |
| object[key] = source[key]; |
| } |
| } |
| } |
| |
| return object; |
| }); |
| |
| module.exports = defaults; |