lepu-test-platform-web/node_modules/es5-ext/array/#/slice/shim.js

37 lines
1.0 KiB
JavaScript

"use strict";
var toInteger = require("../../../number/to-integer")
, toPosInt = require("../../../number/to-pos-integer")
, isPlainArray = require("../../is-plain-array")
, isArray = Array.isArray
, slice = Array.prototype.slice
, objHasOwnProperty = Object.prototype.hasOwnProperty
, max = Math.max;
module.exports = function (start, end) {
var length, result, i;
if (!this || !isArray(this) || isPlainArray(this)) {
return slice.apply(this, arguments);
}
length = toPosInt(this.length);
start = toInteger(start);
if (start < 0) start = max(length + start, 0);
else if (start > length) start = length;
if (end === undefined) {
end = length;
} else {
end = toInteger(end);
if (end < 0) end = max(length + end, 0);
else if (end > length) end = length;
}
if (start > end) start = end;
result = new this.constructor(end - start);
i = 0;
while (start !== end) {
if (objHasOwnProperty.call(this, start)) result[i] = this[start];
++i;
++start;
}
return result;
};