securityos/node_modules/es-abstract/2018/NumberToRawBytes.js

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2024-09-06 15:32:35 +00:00
'use strict';
var $TypeError = require('es-errors/type');
var hasOwnProperty = require('./HasOwnProperty');
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 valueToFloat32Bytes = require('../helpers/valueToFloat32Bytes');
var valueToFloat64Bytes = require('../helpers/valueToFloat64Bytes');
var integerToNBytes = require('../helpers/integerToNBytes');
var keys = require('object-keys');
// https://262.ecma-international.org/8.0/#table-50
var TypeToSizes = {
__proto__: null,
Int8: 1,
Uint8: 1,
Uint8C: 1,
Int16: 2,
Uint16: 2,
Int32: 4,
Uint32: 4,
Float32: 4,
Float64: 8
};
var TypeToAO = {
__proto__: null,
Int8: ToInt8,
Uint8: ToUint8,
Uint8C: ToUint8Clamp,
Int16: ToInt16,
Uint16: ToUint16,
Int32: ToInt32,
Uint32: ToUint32
};
// https://262.ecma-international.org/8.0/#sec-numbertorawbytes
module.exports = function NumberToRawBytes(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 (typeof value !== 'number') {
throw new $TypeError('Assertion failed: `value` must be a Number');
}
if (typeof isLittleEndian !== 'boolean') {
throw new $TypeError('Assertion failed: `isLittleEndian` must be a Boolean');
}
if (type === 'Float32') { // step 1
return valueToFloat32Bytes(value, isLittleEndian);
} else if (type === 'Float64') { // step 2
return valueToFloat64Bytes(value, isLittleEndian);
} // step 3
var n = TypeToSizes[type]; // step 3.a
var convOp = TypeToAO[type]; // step 3.b
var intValue = convOp(value); // step 3.c
return integerToNBytes(intValue, n, isLittleEndian); // step 3.d, 3.e, 4
};