Files
lodash/lodash._baseassign/index.js
2018-02-03 19:13:27 -08:00

120 lines
3.6 KiB
JavaScript

/**
* lodash 3.1.0 (Custom Build) <https://lodash.com/>
* Build: `lodash modern modularize exports="npm" -o ./`
* Copyright 2012-2015 The Dojo Foundation <http://dojofoundation.org/>
* Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
* Copyright 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
* Available under MIT license <https://lodash.com/license>
*/
var baseCopy = require('lodash._basecopy'),
isNative = require('lodash.isnative'),
keys = require('lodash.keys');
/** Native method references. */
var getOwnPropertySymbols = isNative(getOwnPropertySymbols = Object.getOwnPropertySymbols) && getOwnPropertySymbols,
preventExtensions = isNative(Object.preventExtensions = Object.preventExtensions) && preventExtensions;
/** Used as `baseAssign`. */
var nativeAssign = (function() {
// Avoid `Object.assign` in Firefox 34-37 which have an early implementation
// with a now defunct try/catch behavior. See https://bugzilla.mozilla.org/show_bug.cgi?id=1103344
// for more details.
//
// Use `Object.preventExtensions` on a plain object instead of simply using
// `Object('x')` because Chrome and IE fail to throw an error when attempting
// to assign values to readonly indexes of strings in strict mode.
var object = { '1': 0 },
func = preventExtensions && isNative(func = Object.assign) && func;
try { func(preventExtensions(object), 'xo'); } catch(e) {}
return !object[1] && func;
}());
/**
* The base implementation of `_.assign` without support for argument juggling,
* multiple sources, and `customizer` functions.
*
* @private
* @param {Object} object The destination object.
* @param {Object} source The source object.
* @returns {Object} Returns `object`.
*/
var baseAssign = nativeAssign || function(object, source) {
return source == null
? object
: baseCopy(source, getSymbols(source), baseCopy(source, keys(source), object));
};
/**
* Creates an array of the own symbols of `object`.
*
* @private
* @param {Object} object The object to query.
* @returns {Array} Returns the array of symbols.
*/
var getSymbols = !getOwnPropertySymbols ? constant([]) : function(object) {
return getOwnPropertySymbols(toObject(object));
};
/**
* Converts `value` to an object if it is not one.
*
* @private
* @param {*} value The value to process.
* @returns {Object} Returns the object.
*/
function toObject(value) {
return isObject(value) ? value : Object(value);
}
/**
* Checks if `value` is the [language type](https://es5.github.io/#x8) of `Object`.
* (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is an object, else `false`.
* @example
*
* _.isObject({});
* // => true
*
* _.isObject([1, 2, 3]);
* // => true
*
* _.isObject(1);
* // => false
*/
function isObject(value) {
// Avoid a V8 JIT bug in Chrome 19-20.
// See https://code.google.com/p/v8/issues/detail?id=2291 for more details.
var type = typeof value;
return type == 'function' || (!!value && type == 'object');
}
/**
* Creates a function that returns `value`.
*
* @static
* @memberOf _
* @category Utility
* @param {*} value The value to return from the new function.
* @returns {Function} Returns the new function.
* @example
*
* var object = { 'user': 'fred' };
* var getter = _.constant(object);
*
* getter() === object;
* // => true
*/
function constant(value) {
return function() {
return value;
};
}
module.exports = baseAssign;