wikimedia/mediawiki-extensions-MobileFrontend

/**
 * Class for managing modules
 *
 * A module in this context is essentially a Javascript class (not to be confused with
 * ResourceLoader modules).
 *
 * @class ModuleLoader
 */
function ModuleLoader() {
    /**
     * @property {Object} register of defined modules
     * @private
     */
    this._register = {};
}

ModuleLoader.prototype = {
    /**
     * Require (import) a module previously defined using define().
     * Searches core module registry using ResourceLoader require before consulting
     * its own local registry. This method is deprecated, please do not use.
     *
     * @memberof ModuleLoader
     * @instance
     * @param {string} id Required module id.
     * @return {Object} Required module, can be any JavaScript object.
     */
    require( id ) {
        const registry = this._register;

        /**
         * @return {Object} Module
         */
        function localRequire() {
            if ( !Object.hasOwnProperty.call( registry, id ) ) {
                throw new Error( 'MobileFrontend Module not found: ' + id );
            }
            return registry[id];
        }

        const args = id.split( '/' );
        try {
            const module = __non_webpack_require__( args[0] );
            if ( module[args[1]] ) {
                return module[args[1]];
            } else {
                return localRequire();
            }
        } catch ( e ) {
            return localRequire();
        }
    },

    /**
     * Define a module which can be later required (imported) using require().
     *
     * @memberof ModuleLoader
     * @instance
     * @param {string} id Defined module id.
     * @param {Object} obj Defined module body, can be any JavaScript object.
     * @return {Object}
     */
    define( id, obj ) {
        const self = this;

        if ( Object.hasOwnProperty.call( this._register, id ) ) {
            throw new Error( 'Module already exists: ' + id );
        }
        this._register[id] = obj;
        // return an object of additionally functions to do with the registered module
        return {
            /**
             * @see ModuleLoader#deprecate
             * @param {string} deprecatedId Defined module id, which is deprecated.
             * @ignore
             */
            deprecate( deprecatedId ) {
                self.deprecate( deprecatedId, obj, id );
            }
        };
    },

    /**
     * Deprecate a module and give an replacement (if there is any).
     *
     * @memberof ModuleLoader
     * @instance
     * @param {string} id Defined module id, which is deprecated.
     * @param {Object} obj Defined module body, can be any JavaScript object.
     * @param {string} [replacement] Give an optional replacement for this module (which
     * needs to be already defined!)
     */
    deprecate( id, obj, replacement ) {
        let msg;
        if ( replacement ) {
            // add an alternative for this module, if any given
            msg = 'Use ' + replacement + ' instead.';
        }
        // register it as a deprecated one
        mw.log.deprecate( this._register, id, obj, msg );
    }
};

module.exports = ModuleLoader;