main.js (1727B)
1 /** 2 * @license Apache-2.0 3 * 4 * Copyright (c) 2018 The Stdlib Authors. 5 * 6 * Licensed under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 'use strict'; 20 21 // MODULES // 22 23 var isUint8ClampedArray = require( './../../is-uint8clampedarray' ); 24 var GlobalUint8ClampedArray = require( './uint8clampedarray.js' ); 25 26 27 // MAIN // 28 29 /** 30 * Tests for native `Uint8ClampedArray` support. 31 * 32 * @returns {boolean} boolean indicating if an environment has `Uint8ClampedArray` support 33 * 34 * @example 35 * var bool = hasUint8ClampedArraySupport(); 36 * // returns <boolean> 37 */ 38 function hasUint8ClampedArraySupport() { // eslint-disable-line id-length 39 var bool; 40 var arr; 41 42 if ( typeof GlobalUint8ClampedArray !== 'function' ) { 43 return false; 44 } 45 // Test basic support... 46 try { 47 arr = new GlobalUint8ClampedArray( [ -1, 0, 1, 3.14, 4.99, 255, 256 ] ); 48 bool = ( 49 isUint8ClampedArray( arr ) && 50 arr[ 0 ] === 0 && // clamped 51 arr[ 1 ] === 0 && 52 arr[ 2 ] === 1 && 53 arr[ 3 ] === 3 && // round to nearest 54 arr[ 4 ] === 5 && // round to nearest 55 arr[ 5 ] === 255 && 56 arr[ 6 ] === 255 // clamped 57 ); 58 } catch ( err ) { // eslint-disable-line no-unused-vars 59 bool = false; 60 } 61 return bool; 62 } 63 64 65 // EXPORTS // 66 67 module.exports = hasUint8ClampedArraySupport;