Internet-programming_PIbd-2.../Library/node_modules/es-abstract/2021/ValidateAtomicAccess.js

60 lines
1.5 KiB
JavaScript

'use strict';
var GetIntrinsic = require('get-intrinsic');
var $RangeError = GetIntrinsic('%RangeError%');
var $TypeError = GetIntrinsic('%TypeError%');
var ToIndex = require('./ToIndex');
var isTypedArray = require('is-typed-array');
var typedArrayByteOffset = require('typed-array-byte-offset');
var typedArrayLength = require('typed-array-length');
var whichTypedArray = require('which-typed-array');
var table60 = {
__proto__: null,
$Int8Array: 1,
$Uint8Array: 1,
$Uint8ClampedArray: 1,
$Int16Array: 2,
$Uint16Array: 2,
$Int32Array: 4,
$Uint32Array: 4,
$BigInt64Array: 8,
$BigUint64Array: 8,
$Float32Array: 4,
$Float64Array: 8
};
// https://262.ecma-international.org/12.0/#sec-validateatomicaccess
module.exports = function ValidateAtomicAccess(typedArray, requestIndex) {
if (!isTypedArray(typedArray)) {
throw new $TypeError('Assertion failed: `typedArray` must be a TypedArray'); // step 1
}
var length = typedArrayLength(typedArray); // step 2
var accessIndex = ToIndex(requestIndex); // step 3
/*
// this assertion can never be reached
if (!(accessIndex >= 0)) {
throw new $TypeError('Assertion failed: accessIndex >= 0'); // step 4
}
*/
if (accessIndex >= length) {
throw new $RangeError('index out of range'); // step 5
}
var arrayTypeName = whichTypedArray(typedArray); // step 6
var elementSize = table60['$' + arrayTypeName]; // step 7
var offset = typedArrayByteOffset(typedArray); // step 8
return (accessIndex * elementSize) + offset; // step 9
};