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- 'use strict';
- var $TypeError = require('es-errors/type');
- var IsFixedLengthArrayBuffer = require('./IsFixedLengthArrayBuffer');
- var IsViewOutOfBounds = require('./IsViewOutOfBounds');
- var isDataViewWithBufferWitnessRecord = require('../helpers/records/data-view-with-buffer-witness-record');
- var dataViewBuffer = require('data-view-buffer');
- var dataViewByteLength = require('data-view-byte-length');
- var dataViewByteOffset = require('data-view-byte-offset');
- // https://262.ecma-international.org/15.0/#sec-getviewbytelength
- module.exports = function GetViewByteLength(viewRecord) {
- if (!isDataViewWithBufferWitnessRecord(viewRecord)) {
- throw new $TypeError('Assertion failed: `viewRecord` must be a DataView with Buffer Witness Record');
- }
- if (IsViewOutOfBounds(viewRecord)) {
- throw new $TypeError('Assertion failed: `viewRecord` is out of bounds'); // step 1
- }
- var view = viewRecord['[[Object]]']; // step 2
- var viewByteLength = dataViewByteLength(view); // view.[[ByteLength]]
- if (viewByteLength !== 'AUTO') {
- return viewByteLength; // step 3
- }
- if (IsFixedLengthArrayBuffer(dataViewBuffer(view))) {
- throw new $TypeError('Assertion failed: DataView’s ArrayBuffer is not fixed length'); // step 4
- }
- var byteOffset = dataViewByteOffset(view); // step 5
- var byteLength = viewRecord['[[CachedBufferByteLength]]']; // step 6
- if (byteLength === 'DETACHED') {
- throw new $TypeError('Assertion failed: DataView’s ArrayBuffer is detached'); // step 7
- }
- return byteLength - byteOffset; // step 8
- };
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