79 lines
1.8 KiB
JavaScript
79 lines
1.8 KiB
JavaScript
/**
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* @license Apache-2.0
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*
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* Copyright (c) 2018 The Stdlib Authors.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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'use strict';
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// MODULES //
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var getOwnPropertySymbols = require( './../../property-symbols' );
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var getPrototypeOf = require( './../../get-prototype-of' );
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var isWritableProperty = require( '@stdlib/assert/is-writable-property' );
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var hasOwnProp = require( '@stdlib/assert/has-own-property' );
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// MAIN //
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/**
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* Returns an array of an object's own and inherited writable symbol properties.
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*
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* @param {*} value - input object
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* @returns {Array} a list of own and inherited writable symbol properties
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*
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* @example
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* var symbols = writablePropertySymbolsIn( {} );
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*/
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function writablePropertySymbolsIn( value ) {
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var symbols;
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var cache;
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var obj;
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var tmp;
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var k;
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var i;
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if ( value === null || value === void 0 ) {
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return [];
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}
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// Cast the value to an object:
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obj = Object( value );
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// Walk the prototype chain collecting all writable symbol properties...
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symbols = [];
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cache = {};
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do {
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tmp = getOwnPropertySymbols( obj );
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for ( i = 0; i < tmp.length; i++ ) {
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k = tmp[ i ];
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if (
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hasOwnProp( cache, k ) === false &&
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isWritableProperty( obj, k )
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) {
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symbols.push( k );
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}
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cache[ k ] = true;
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}
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obj = getPrototypeOf( obj );
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} while ( obj );
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return symbols;
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}
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// EXPORTS //
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module.exports = writablePropertySymbolsIn;
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