Chris@0: /**
Chris@0:  * @file
Chris@0:  *
Chris@0:  * Watch changes to *.es6.js files and compile them to ES5 during development.
Chris@0:  *
Chris@0:  * @internal This file is part of the core javascript build process and is only
Chris@0:  * meant to be used in that context.
Chris@0:  */
Chris@0: 
Chris@0: 'use strict';
Chris@0: 
Chris@0: const fs = require('fs');
Chris@0: const path = require('path');
Chris@0: const chokidar = require('chokidar');
Chris@0: 
Chris@0: const changeOrAdded = require('./changeOrAdded');
Chris@0: const log = require('./log');
Chris@0: 
Chris@0: // Match only on .es6.js files.
Chris@0: const fileMatch = './**/*.es6.js';
Chris@0: // Ignore everything in node_modules
Chris@0: const watcher = chokidar.watch(fileMatch, {
Chris@0:   ignoreInitial: true,
Chris@0:   ignored: './node_modules/**'
Chris@0: });
Chris@0: 
Chris@0: const unlinkHandler = (err) => {
Chris@0:   if (err) {
Chris@0:     log(err);
Chris@0:   }
Chris@0: };
Chris@0: 
Chris@0: // Watch for filesystem changes.
Chris@0: watcher
Chris@0:   .on('add', changeOrAdded)
Chris@0:   .on('change', changeOrAdded)
Chris@0:   .on('unlink', (filePath) => {
Chris@0:     const fileName = filePath.slice(0, -7);
Chris@0:     fs.stat(`${fileName}.js`, () => {
Chris@0:       fs.unlink(`${fileName}.js`, unlinkHandler);
Chris@0:     });
Chris@0:   })
Chris@0:   .on('ready', () => log(`Watching '${fileMatch}' for changes.`));