45 lines
1.2 KiB
JavaScript
45 lines
1.2 KiB
JavaScript
// Taken from: https://github.com/paulmillr/es6-shim/
|
|
|
|
"use strict";
|
|
|
|
var toInteger = require("../../../number/to-integer")
|
|
, toPosInt = require("../../../number/to-pos-integer")
|
|
, validValue = require("../../../object/valid-value")
|
|
, objHasOwnProperty = Object.prototype.hasOwnProperty
|
|
, max = Math.max
|
|
, min = Math.min;
|
|
|
|
module.exports = function (target, start /*, end*/) {
|
|
var arr = validValue(this)
|
|
, end = arguments[2]
|
|
, length = toPosInt(arr.length)
|
|
, to
|
|
, from
|
|
, fin
|
|
, count
|
|
, direction;
|
|
|
|
target = toInteger(target);
|
|
start = toInteger(start);
|
|
end = end === undefined ? length : toInteger(end);
|
|
|
|
to = target < 0 ? max(length + target, 0) : min(target, length);
|
|
from = start < 0 ? max(length + start, 0) : min(start, length);
|
|
fin = end < 0 ? max(length + end, 0) : min(end, length);
|
|
count = min(fin - from, length - to);
|
|
direction = 1;
|
|
|
|
if (from < to && to < from + count) {
|
|
direction = -1;
|
|
from += count - 1;
|
|
to += count - 1;
|
|
}
|
|
while (count > 0) {
|
|
if (objHasOwnProperty.call(arr, from)) arr[to] = arr[from];
|
|
else delete arr[from];
|
|
from += direction;
|
|
to += direction;
|
|
count -= 1;
|
|
}
|
|
return arr;
|
|
};
|