joplin/packages/app-mobile/metro.config.js

/**
 * Metro configuration for React Native
 * https://github.com/facebook/react-native
 *
 * @format
 */

// The technique below to get the symlinked packages to work with the Metro
// bundler comes from this comment:
//
// https://github.com/facebook/metro/issues/1#issuecomment-501143843
//
// Perhaps also investigate this technique as it's specifically for Lerna:
//
// https://github.com/facebook/metro/issues/1#issuecomment-511228599

const path = require('path');

module.exports = {
	transformer: {
		getTransformOptions: async () => ({
			transform: {
				experimentalImportSupport: false,
				inlineRequires: true,
			},
		}),
	},
	resolver: {
		// This configuration allows you to build React-Native modules and
		//     * test them without having to publish the module. Any exports provided
		//     * by your source should be added to the "target" parameter. Any import
		//     * not matched by a key in target will have to be located in the embedded
		//     * app's node_modules directory.
		//
		extraNodeModules: new Proxy(
			// The first argument to the Proxy constructor is passed as
			//        * "target" to the "get" method below.
			//        * Put the names of the libraries included in your reusable
			//        * module as they would be imported when the module is actually used.
			//
			{
				'@joplin/lib': path.resolve(__dirname, '../lib/'),
				'@joplin/renderer': path.resolve(__dirname, '../renderer/'),
				'@joplin/tools': path.resolve(__dirname, '../tools/'),
				'@joplin/fork-htmlparser2': path.resolve(__dirname, '../fork-htmlparser2/'),
			},
			{
				get: (target, name) => {
					if (target.hasOwnProperty(name)) {
						return target[name];
					}
					return path.join(process.cwd(), `node_modules/${name}`);
				},
			}
		),
	},
	projectRoot: path.resolve(__dirname),
	watchFolders: [
		path.resolve(__dirname, '../lib'),
		path.resolve(__dirname, '../renderer'),
		path.resolve(__dirname, '../tools'),
		path.resolve(__dirname, '../fork-htmlparser2'),
	],
};