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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