time-to-botec/js/node_modules/@stdlib/assert/has-uint8array-support/lib/main.js

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/**
* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
// MODULES //
var isUint8Array = require( './../../is-uint8array' );
var UINT8_MAX = require( '@stdlib/constants/uint8/max' );
var GlobalUint8Array = require( './uint8array.js' );
// MAIN //
/**
* Tests for native `Uint8Array` support.
*
* @returns {boolean} boolean indicating if an environment has `Uint8Array` support
*
* @example
* var bool = hasUint8ArraySupport();
* // returns <boolean>
*/
function hasUint8ArraySupport() {
var bool;
var arr;
if ( typeof GlobalUint8Array !== 'function' ) {
return false;
}
// Test basic support...
try {
arr = [ 1, 3.14, -3.14, UINT8_MAX+1, UINT8_MAX+2 ];
arr = new GlobalUint8Array( arr );
bool = (
isUint8Array( arr ) &&
arr[ 0 ] === 1 &&
arr[ 1 ] === 3 && // truncation
arr[ 2 ] === UINT8_MAX-2 && // truncation and wrap around
arr[ 3 ] === 0 && // wrap around
arr[ 4 ] === 1 // wrap around
);
} catch ( err ) { // eslint-disable-line no-unused-vars
bool = false;
}
return bool;
}
// EXPORTS //
module.exports = hasUint8ArraySupport;