mh-two-thousand-and-two
2024-04-12 7fc6dbf547b8899d949b67cdec36b96a7d1701c7
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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
};