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- 'use strict';
- var $TypeError = require('es-errors/type');
- var IsDetachedBuffer = require('./IsDetachedBuffer');
- 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-isviewoutofbounds
- module.exports = function IsViewOutOfBounds(viewRecord) {
- if (!isDataViewWithBufferWitnessRecord(viewRecord)) {
- throw new $TypeError('Assertion failed: `viewRecord` must be a DataView With Buffer Witness Record');
- }
- var view = viewRecord['[[Object]]']; // step 1
- var bufferByteLength = viewRecord['[[CachedBufferByteLength]]']; // step 2
- if (IsDetachedBuffer(dataViewBuffer(view)) !== (bufferByteLength === 'DETACHED')) {
- // step 3
- throw new $TypeError('Assertion failed: `IsDetachedBuffer(dataViewBuffer(view))` must be true if and only if `bufferByteLength === ~DETACHED~');
- }
- if (bufferByteLength === 'DETACHED') {
- return true; // step 4
- }
- var byteOffsetStart = dataViewByteOffset(view); // step 5
- var dvByteLength = dataViewByteLength(view);
- var byteOffsetEnd = dvByteLength === 'AUTO' ? bufferByteLength : byteOffsetStart + dvByteLength; // steps 6 - 7
- if (byteOffsetStart > bufferByteLength || byteOffsetEnd > bufferByteLength) {
- return true; // step 8
- }
- // 9. NOTE: 0-length DataViews are not considered out-of-bounds.
- return false; // step 10
- };
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