lix-website/themes/lix/assets/bootstrap/node_modules/es-abstract/2021/CloneArrayBuffer.js
2024-04-26 22:49:34 -06:00

48 lines
1.8 KiB
JavaScript

'use strict';
var $TypeError = require('es-errors/type');
var GetPrototypeFromConstructor = require('./GetPrototypeFromConstructor');
var IsConstructor = require('./IsConstructor');
var IsDetachedBuffer = require('./IsDetachedBuffer');
var OrdinarySetPrototypeOf = require('./OrdinarySetPrototypeOf');
var isInteger = require('../helpers/isInteger');
var isArrayBuffer = require('is-array-buffer');
var arrayBufferSlice = require('arraybuffer.prototype.slice');
// https://262.ecma-international.org/12.0/#sec-clonearraybuffer
module.exports = function CloneArrayBuffer(srcBuffer, srcByteOffset, srcLength, cloneConstructor) {
if (!isArrayBuffer(srcBuffer)) {
throw new $TypeError('Assertion failed: `srcBuffer` must be an ArrayBuffer instance');
}
if (!isInteger(srcByteOffset) || srcByteOffset < 0) {
throw new $TypeError('Assertion failed: `srcByteOffset` must be a non-negative integer');
}
if (!isInteger(srcLength) || srcLength < 0) {
throw new $TypeError('Assertion failed: `srcLength` must be a non-negative integer');
}
if (!IsConstructor(cloneConstructor)) {
throw new $TypeError('Assertion failed: `cloneConstructor` must be a constructor');
}
// 3. Let targetBuffer be ? AllocateArrayBuffer(cloneConstructor, srcLength).
var proto = GetPrototypeFromConstructor(cloneConstructor, '%ArrayBufferPrototype%'); // step 3, kinda
if (IsDetachedBuffer(srcBuffer)) {
throw new $TypeError('`srcBuffer` must not be a detached ArrayBuffer'); // step 4
}
/*
5. Let srcBlock be srcBuffer.[[ArrayBufferData]].
6. Let targetBlock be targetBuffer.[[ArrayBufferData]].
7. Perform CopyDataBlockBytes(targetBlock, 0, srcBlock, srcByteOffset, srcLength).
*/
var targetBuffer = arrayBufferSlice(srcBuffer, srcByteOffset, srcByteOffset + srcLength); // steps 5-7
OrdinarySetPrototypeOf(targetBuffer, proto); // step 3
return targetBuffer; // step 8
};