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- 'use strict';
- var GetIntrinsic = require('get-intrinsic');
- var $floor = GetIntrinsic('%Math.floor%');
- var $log = GetIntrinsic('%Math.log%');
- var $log2E = GetIntrinsic('%Math.LOG2E%');
- var $log2 = GetIntrinsic('%Math.log2%', true) || function log2(x) {
- return $log(x) * $log2E;
- };
- var $parseInt = GetIntrinsic('%parseInt%');
- var $pow = GetIntrinsic('%Math.pow%');
- var $Number = GetIntrinsic('%Number%');
- var $TypeError = GetIntrinsic('%TypeError%');
- var $BigInt = GetIntrinsic('%BigInt%', true);
- var callBound = require('call-bind/callBound');
- var $reverse = callBound('Array.prototype.reverse');
- var $numberToString = callBound('Number.prototype.toString');
- var $strSlice = callBound('String.prototype.slice');
- var abs = require('./abs');
- var hasOwnProperty = require('./HasOwnProperty');
- var ToBigInt64 = require('./ToBigInt64');
- var ToBigUint64 = require('./ToBigUint64');
- var ToInt16 = require('./ToInt16');
- var ToInt32 = require('./ToInt32');
- var ToInt8 = require('./ToInt8');
- var ToUint16 = require('./ToUint16');
- var ToUint32 = require('./ToUint32');
- var ToUint8 = require('./ToUint8');
- var ToUint8Clamp = require('./ToUint8Clamp');
- var Type = require('./Type');
- var isNaN = require('../helpers/isNaN');
- var isFinite = require('../helpers/isFinite');
- var keys = require('object-keys');
- // https://262.ecma-international.org/11.0/#table-the-typedarray-constructors
- var TypeToSizes = {
- __proto__: null,
- Int8: 1,
- Uint8: 1,
- Uint8C: 1,
- Int16: 2,
- Uint16: 2,
- Int32: 4,
- Uint32: 4,
- BigInt64: 8,
- BigUint64: 8,
- Float32: 4,
- Float64: 8
- };
- var TypeToAO = {
- __proto__: null,
- Int8: ToInt8,
- Uint8: ToUint8,
- Uint8C: ToUint8Clamp,
- Int16: ToInt16,
- Uint16: ToUint16,
- Int32: ToInt32,
- Uint32: ToUint32,
- BigInt64: ToBigInt64,
- BigUint64: ToBigUint64
- };
- // https://262.ecma-international.org/11.0/#sec-numerictorawbytes
- module.exports = function NumericToRawBytes(type, value, isLittleEndian) {
- if (typeof type !== 'string' || !hasOwnProperty(TypeToSizes, type)) {
- throw new $TypeError('Assertion failed: `type` must be a TypedArray element type: ' + keys(TypeToSizes));
- }
- if (Type(value) !== 'Number' && Type(value) !== 'BigInt') {
- throw new $TypeError('Assertion failed: `value` must be a Number or a BigInt');
- }
- if (Type(isLittleEndian) !== 'Boolean') {
- throw new $TypeError('Assertion failed: `isLittleEndian` must be a Boolean');
- }
- var rawBytes = [];
- var exponent;
- if (type === 'Float32') { // step 1
- if (isNaN(value)) {
- return isLittleEndian ? [0, 0, 192, 127] : [127, 192, 0, 0]; // hardcoded
- }
- var leastSig;
- if (value === 0) {
- leastSig = Object.is(value, -0) ? 0x80 : 0;
- return isLittleEndian ? [0, 0, 0, leastSig] : [leastSig, 0, 0, 0];
- }
- if (!isFinite(value)) {
- leastSig = value < 0 ? 255 : 127;
- return isLittleEndian ? [0, 0, 128, leastSig] : [leastSig, 128, 0, 0];
- }
- var sign = value < 0 ? 1 : 0;
- value = abs(value); // eslint-disable-line no-param-reassign
- exponent = 0;
- while (value >= 2) {
- exponent += 1;
- value /= 2; // eslint-disable-line no-param-reassign
- }
- while (value < 1) {
- exponent -= 1;
- value *= 2; // eslint-disable-line no-param-reassign
- }
- var mantissa = value - 1;
- mantissa *= $pow(2, 23);
- mantissa = $floor(mantissa);
- exponent += 127;
- exponent = exponent << 23;
- var result = sign << 31;
- result |= exponent;
- result |= mantissa;
- var byte0 = result & 255;
- result = result >> 8;
- var byte1 = result & 255;
- result = result >> 8;
- var byte2 = result & 255;
- result = result >> 8;
- var byte3 = result & 255;
- if (isLittleEndian) {
- return [byte0, byte1, byte2, byte3];
- }
- return [byte3, byte2, byte1, byte0];
- } else if (type === 'Float64') { // step 2
- if (value === 0) {
- leastSig = Object.is(value, -0) ? 0x80 : 0;
- return isLittleEndian ? [0, 0, 0, 0, 0, 0, 0, leastSig] : [leastSig, 0, 0, 0, 0, 0, 0, 0];
- }
- if (isNaN(value)) {
- return isLittleEndian ? [0, 0, 0, 0, 0, 0, 248, 127] : [127, 248, 0, 0, 0, 0, 0, 0];
- }
- if (!isFinite(value)) {
- var infBytes = value < 0 ? [0, 0, 0, 0, 0, 0, 240, 255] : [0, 0, 0, 0, 0, 0, 240, 127];
- return isLittleEndian ? infBytes : $reverse(infBytes);
- }
- var isNegative = value < 0;
- if (isNegative) { value = -value; } // eslint-disable-line no-param-reassign
- exponent = $floor($log2(value));
- var significand = (value / $pow(2, exponent)) - 1;
- var bitString = '';
- for (var i = 0; i < 52; i++) {
- significand *= 2;
- if (significand >= 1) {
- bitString += '1';
- significand -= 1;
- } else {
- bitString += '0';
- }
- }
- exponent += 1023;
- var exponentBits = $numberToString(exponent, 2);
- while (exponentBits.length < 11) { exponentBits = '0' + exponentBits; }
- var fullBitString = (isNegative ? '1' : '0') + exponentBits + bitString;
- while (fullBitString.length < 64) { fullBitString = '0' + fullBitString; }
- for (i = 0; i < 8; i++) {
- rawBytes[i] = $parseInt($strSlice(fullBitString, i * 8, (i + 1) * 8), 2);
- }
- return isLittleEndian ? $reverse(rawBytes) : rawBytes;
- } // step 3
- var n = TypeToSizes[type]; // step 3.a
- var convOp = TypeToAO[type]; // step 3.b
- var intValue = convOp(value); // step 3.c
- var isBigInt = type === 'BigInt64' || type === 'BigUint64';
- /*
- if (intValue >= 0) { // step 3.d
- // Let rawBytes be a List containing the n-byte binary encoding of intValue. If isLittleEndian is false, the bytes are ordered in big endian order. Otherwise, the bytes are ordered in little endian order.
- } else { // step 3.e
- // Let rawBytes be a List containing the n-byte binary 2's complement encoding of intValue. If isLittleEndian is false, the bytes are ordered in big endian order. Otherwise, the bytes are ordered in little endian order.
- }
- */
- if (intValue < 0) {
- intValue = intValue >>> 0;
- }
- var OxFF = isBigInt ? $BigInt(0xFF) : 0xFF;
- var eight = isBigInt ? $BigInt(8) : 8;
- for (i = 0; i < n; i++) {
- rawBytes[isLittleEndian ? i : n - 1 - i] = $Number(intValue & OxFF);
- intValue = intValue >> eight;
- }
- return rawBytes; // step 4
- };
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