85 lines
2.6 KiB
Plaintext
85 lines
2.6 KiB
Plaintext
'use strict';
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var GetIntrinsic = require('get-intrinsic');
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var $ArrayBuffer = GetIntrinsic('%ArrayBuffer%', true);
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var $Uint8Array = GetIntrinsic('%Uint8Array%', true);
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var IsDetachedBuffer = require('es-abstract/2023/IsDetachedBuffer');
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var IsSharedArrayBuffer = require('es-abstract/2023/IsSharedArrayBuffer');
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var max = require('es-abstract/2023/max');
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var min = require('es-abstract/2023/min');
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var SpeciesConstructor = require('es-abstract/2023/SpeciesConstructor');
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var ToIntegerOrInfinity = require('es-abstract/2023/ToIntegerOrInfinity');
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var arrayBufferByteLength = require('array-buffer-byte-length');
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var isArrayBuffer = require('is-array-buffer');
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var $TypeError = require('es-errors/type');
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module.exports = function slice(start, end) {
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var O = this; // step 1
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if (!isArrayBuffer(O) || IsSharedArrayBuffer(O) || IsDetachedBuffer(O)) {
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throw new $TypeError('receiver must be a non-detached, non-shared ArrayBuffer'); // steps 2-4
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}
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var len = arrayBufferByteLength(O); // step 5
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var relativeStart = ToIntegerOrInfinity(start); // step 6
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var first;
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if (relativeStart === -Infinity) {
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first = 0; // step 7
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} else if (relativeStart < 0) {
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first = max(len + relativeStart, 0); // step 8
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} else {
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first = min(relativeStart, len); // step 9
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}
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var relativeEnd = typeof end === 'undefined' ? len : ToIntegerOrInfinity(end); // step 10
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var final;
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if (relativeEnd === -Infinity) {
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final = 0; // step 11
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} else if (relativeEnd < 0) {
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final = max(len + relativeEnd, 0); // step 12
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} else {
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final = min(relativeEnd, len); // step 13
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}
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var newLen = max(final - first, 0); // step 14
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var Ctor = SpeciesConstructor(O, $ArrayBuffer); // step 15
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var new$ = new Ctor(newLen); // step 16
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if (!isArrayBuffer(new$) || IsSharedArrayBuffer(new$) || IsDetachedBuffer(new$)) {
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throw new $TypeError('Species constructor must produce a non-detached, non-shared Array Buffer'); // steps 17-19
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}
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if (new$ === O) {
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throw new $TypeError('new ArrayBuffer should not have been the same as the receiver'); // step 20
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}
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if (arrayBufferByteLength(new$) < newLen) {
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throw new $TypeError('new ArrayBuffer\'s byteLength must be at least the requested length'); // step 21
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}
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if (IsDetachedBuffer(O)) {
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throw new $TypeError('receiver became an detached ArrayBuffer'); // step 23
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}
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/*
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24. Let fromBuf be O.[[ArrayBufferData]].
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25. Let toBuf be new.[[ArrayBufferData]].
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26. Perform CopyDataBlockBytes(toBuf, 0, fromBuf, first, newLen).
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*/
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var sourceArr = new $Uint8Array(O);
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var destArr = new $Uint8Array(new$);
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for (var i = start, ii = 0; i < end; i++, ii++) {
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destArr[ii] = sourceArr[i];
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}
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return new$; // step 27
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};
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