time-to-botec/squiggle/node_modules/@stdlib/utils/inherited-property-descriptor/lib/main.js
NunoSempere b6addc7f05 feat: add the node modules
Necessary in order to clearly see the squiggle hotwiring.
2022-12-03 12:44:49 +00:00

86 lines
2.5 KiB
JavaScript

/**
* @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 MAX_SAFE_INTEGER = require( '@stdlib/constants/float64/max-safe-integer' );
var isPositiveInteger = require( '@stdlib/assert/is-positive-integer' ).isPrimitive;
var getOwnPropertyDescriptor = require( './../../property-descriptor' );
var getPrototypeOf = require( './../../get-prototype-of' );
// MAIN //
/**
* Returns a property descriptor for an object's inherited property.
*
* ## Notes
*
* - In contrast to the built-in `Object.getOwnPropertyDescriptor()`, this function returns `null` if provided `undefined` or `null`, rather than throwing an error.
* - In contrast to the built-in `Object.getOwnPropertyDescriptor()`, this function returns `null` if an object does not have an inherited provided property, rather than `undefined`.
*
* @private
* @param {*} value - input object
* @param {(string|symbol)} property - property
* @param {PositiveInteger} [level] - inheritance level
* @throws {TypeError} third argument must be a positive integer
* @returns {(Object|null)} property descriptor or null
*
* @example
* var desc = inheritedPropertyDescriptor( {}, 'toString' );
* // returns {...}
*/
function inheritedPropertyDescriptor( value, property, level ) { // eslint-disable-line id-length
var desc;
var obj;
var N;
var n;
if ( arguments.length > 2 ) {
if ( !isPositiveInteger( level ) ) {
throw new TypeError( 'invalid argument. Third argument must be a positive integer. Value: `' + level + '`.' );
}
N = level;
} else {
N = MAX_SAFE_INTEGER;
}
if ( value === null || value === void 0 ) {
return null;
}
// Get the value's prototype:
obj = getPrototypeOf( value );
// Walk the prototype chain in search of a specified property...
n = 1;
while ( obj && n <= N ) {
desc = getOwnPropertyDescriptor( obj, property );
if ( desc ) {
return desc;
}
obj = getPrototypeOf( obj );
n += 1;
}
return null;
}
// EXPORTS //
module.exports = inheritedPropertyDescriptor;