check.js

/**
* @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 RE = require( './fixtures/re.js' );
var nodeList = require( './fixtures/nodelist.js' );
var typedarray = require( './fixtures/typedarray.js' );


// MAIN //

/**
* Checks whether a polyfill is needed when using the `typeof` operator.
*
* @private
* @returns {boolean} boolean indicating whether a polyfill is needed
*/
function check() {
	if (
		// Chrome 1-12 returns 'function' for regular expression instances (see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/typeof):
		typeof RE === 'function' ||

		// Safari 8 returns 'object' for typed array and weak map constructors (underscore #1929):
		typeof typedarray === 'object' ||

		// PhantomJS 1.9 returns 'function' for `NodeList` instances (underscore #2236):
		typeof nodeList === 'function'
	) {
		return true;
	}
	return false;
}


// EXPORTS //

module.exports = check;