time-to-botec

Benchmark sampling in different programming languages
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main.js (2061B)

      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 getOwnPropertyDescriptor = require( './../../property-descriptor' );
     24 var getPrototypeOf = require( './../../get-prototype-of' );
     25 
     26 
     27 // MAIN //
     28 
     29 /**
     30 * Returns a property descriptor for an object's own or inherited property.
     31 *
     32 * ## Notes
     33 *
     34 * -   In contrast to the built-in `Object.getOwnPropertyDescriptor()`, this function returns `null` if provided `undefined` or `null`, rather than throwing an error.
     35 * -   In contrast to the built-in `Object.getOwnPropertyDescriptor()`, this function returns `null` if an object does not have a provided property, rather than `undefined`.
     36 *
     37 * @private
     38 * @param {*} value - input object
     39 * @param {(string|symbol)} property - property
     40 * @returns {(Object|null)} property descriptor or null
     41 *
     42 * @example
     43 * var obj = {
     44 *     'beep': 'boop',
     45 *     'foo': 3.14
     46 * };
     47 *
     48 * var desc = propertyDescriptorIn( obj, 'foo' );
     49 * // returns {'configurable':true,'enumerable':true,'writable':true,'value':3.14}
     50 */
     51 function propertyDescriptorIn( value, property ) {
     52 	var desc;
     53 	var obj;
     54 
     55 	if ( value === null || value === void 0 ) {
     56 		return null;
     57 	}
     58 	// Cast the value to an object:
     59 	obj = Object( value );
     60 
     61 	// Walk the prototype chain in search of a specified property...
     62 	do {
     63 		desc = getOwnPropertyDescriptor( obj, property );
     64 		if ( desc ) {
     65 			return desc;
     66 		}
     67 		obj = getPrototypeOf( obj );
     68 	} while ( obj );
     69 
     70 	return null;
     71 }
     72 
     73 
     74 // EXPORTS //
     75 
     76 module.exports = propertyDescriptorIn;