| 1 | 'use strict';
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| 2 |
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| 3 | var $TypeError = require('es-errors/type');
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| 4 |
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| 5 | // https://262.ecma-international.org/15.0/#sec-arraybufferbytelength
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| 6 |
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| 7 | var IsDetachedBuffer = require('./IsDetachedBuffer');
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| 8 |
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| 9 | var isArrayBuffer = require('is-array-buffer');
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| 10 | var isSharedArrayBuffer = require('is-shared-array-buffer');
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| 11 | var arrayBufferByteLength = require('array-buffer-byte-length');
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| 12 |
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| 13 | var callBound = require('call-bound');
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| 14 | var $sabByteLength = callBound('SharedArrayBuffer.prototype.byteLength', true);
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| 15 |
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| 16 | var isGrowable = false; // TODO: support this
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| 17 |
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| 18 | module.exports = function ArrayBufferByteLength(arrayBuffer, order) {
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| 19 | var isSAB = isSharedArrayBuffer(arrayBuffer);
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| 20 | if (!isArrayBuffer(arrayBuffer) && !isSAB) {
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| 21 | throw new $TypeError('Assertion failed: `arrayBuffer` must be an ArrayBuffer or a SharedArrayBuffer');
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| 22 | }
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| 23 | if (order !== 'SEQ-CST' && order !== 'UNORDERED') {
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| 24 | throw new $TypeError('Assertion failed: `order` must be ~SEQ-CST~ or ~UNORDERED~');
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| 25 | }
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| 26 |
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| 27 | // 1. If IsSharedArrayBuffer(arrayBuffer) is true and arrayBuffer has an [[ArrayBufferByteLengthData]] internal slot, then
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| 28 | // TODO: see if IsFixedLengthArrayBuffer can be used here in the spec instead
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| 29 | if (isSAB && isGrowable) { // step 1
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| 30 | // a. Let bufferByteLengthBlock be arrayBuffer.[[ArrayBufferByteLengthData]].
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| 31 | // b. Let rawLength be GetRawBytesFromSharedBlock(bufferByteLengthBlock, 0, BIGUINT64, true, order).
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| 32 | // c. Let isLittleEndian be the value of the [[LittleEndian]] field of the surrounding agent's Agent Record.
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| 33 | // d. Return ℝ(RawBytesToNumeric(BIGUINT64, rawLength, isLittleEndian)).
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| 34 | }
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| 35 |
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| 36 | if (IsDetachedBuffer(arrayBuffer)) {
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| 37 | throw new $TypeError('Assertion failed: `arrayBuffer` must not be detached'); // step 2
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| 38 | }
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| 39 |
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| 40 | return isSAB ? $sabByteLength(arrayBuffer) : arrayBufferByteLength(arrayBuffer);
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| 41 | };
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