import isArguments from './isArguments.js' import isBuffer from './isBuffer.js' import isIndex from './isIndex.js' import isTypedArray from './isTypedArray.js' /** Used to check objects for own properties. */ /** 用于检查对象的自身属性。 */ const hasOwnProperty = Object.prototype.hasOwnProperty /** * Creates an array of the enumerable property names of the array-like `value`. * 创建类似数组的“值”的可枚举属性名的数组。 * @private * @param {*} value 要查询的值. * @param {boolean} inherited 指定返回继承的属性名. * @returns {Array} 返回属性名数组. */ function arrayLikeKeys(value, inherited) { const isArr = Array.isArray(value) const isArg = !isArr && isArguments(value) const isBuff = !isArr && !isArg && isBuffer(value) const isType = !isArr && !isArg && !isBuff && isTypedArray(value) const skipIndexes = isArr || isArg || isBuff || isType const length = value.length const result = new Array(skipIndexes ? length : 0) let index = skipIndexes ? -1 : length while (++index < length) { result[index] = `${index}` } for (const key in value) { if ((inherited || hasOwnProperty.call(value, key)) && !(skipIndexes && ( // Safari 9 has enumerable `arguments.length` in strict mode. (key === 'length' || // Skip index properties. isIndex(key, length)) ))) { result.push(key) } } return result } export default arrayLikeKeys