securityos/node_modules/es-abstract/2015/IntegerIndexedElementSet.js

59 lines
1.7 KiB
JavaScript

'use strict';
var $TypeError = require('es-errors/type');
var IsDetachedBuffer = require('./IsDetachedBuffer');
var IsInteger = require('./IsInteger');
var SetValueInBuffer = require('./SetValueInBuffer');
var ToNumber = require('./ToNumber');
var isNegativeZero = require('is-negative-zero');
var typedArrayBuffer = require('typed-array-buffer');
var typedArrayByteOffset = require('typed-array-byte-offset');
var typedArrayLength = require('typed-array-length');
var whichTypedArray = require('which-typed-array');
var tableTAO = require('./tables/typed-array-objects');
// https://262.ecma-international.org/6.0/#sec-integerindexedelementset
module.exports = function IntegerIndexedElementSet(O, index, value) {
if (typeof index !== 'number') {
throw new $TypeError('`index` must be a Number'); // step 1
}
var arrayTypeName = whichTypedArray(O); // step 12
if (!arrayTypeName) {
throw new $TypeError('`O` must be a TypedArray'); // step 2
}
var numValue = ToNumber(value); // step 3
var buffer = typedArrayBuffer(O); // step 5
if (IsDetachedBuffer(buffer)) {
throw new $TypeError('`O` has a detached buffer'); // step 6
}
if (!IsInteger(index) || isNegativeZero(index)) {
return false; // steps 7 - 8
}
var length = typedArrayLength(O); // step 9
if (index < 0 || index >= length) {
return false; // step 10
}
var offset = typedArrayByteOffset(O); // step 11
var elementType = tableTAO.name['$' + arrayTypeName]; // step 15
var elementSize = tableTAO.size['$' + elementType]; // step 13
var indexedPosition = (index * elementSize) + offset; // step 14
SetValueInBuffer(buffer, indexedPosition, elementType, numValue); // step 16
return true; // step 17
};