Pibd-21_Ievlewa_M.D._Intern.../node_modules/es-abstract/2022/CloneArrayBuffer.js

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2023-12-03 19:52:09 +04:00
'use strict';
var GetIntrinsic = require('get-intrinsic');
var $TypeError = GetIntrinsic('%TypeError%');
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
};