wikimedia/mediawiki-extensions-Wikibase

/**
 * @license GPL-2.0-or-later
 * @author Adrian Heine <adrian.heine@wikimedia.de>
 */
( function () {
    'use strict';

    var EntityStore = require( './store.EntityStore.js' );

    /**
     * An `EntityStore` decorator, adding a cache.
     *
     * @constructor
     * @extends EntityStore
     *
     * @param {EntityStore} store
     */
    module.exports = util.inherit(
        'WbCachingEntityStore',
        EntityStore,
        function ( store ) {
            this._deferreds = {};
            this._store = store;
        },
        {
            /**
             * @type {Object}
             */
            _deferreds: null,

            /**
             * @type {EntityStore}
             */
            _store: null,

            /**
             * @see EntityStore.get
             */
            get: function ( entityId ) {
                if ( !Object.prototype.hasOwnProperty.call( this._deferreds, entityId ) ) {
                    this._deferreds[ entityId ] = this._store.get( entityId );
                }
                return this._deferreds[ entityId ];
            }
        } );
}() );