Use next generation JavaScript, today, with Babel

Issues with the output should be reported on the Babel issue tracker.

$ npm install --save-dev grunt-babel babel-preset-es2015

require('load-grunt-tasks')(grunt); // npm install --save-dev load-grunt-tasks

grunt.initConfig({
	babel: {
		options: {
			sourceMap: true,
			presets: ['es2015']
		},
		dist: {
			files: {
				'dist/app.js': 'src/app.js'
			}
		}
	}
});

grunt.registerTask('default', ['babel']);

See the Babel options, except for filename which is handled for you and inputSourceMap (see below).

inputSourceMap option should be a function which takes two arguments and returns path to the existing source map.

grunt.initConfig({
	babel: {
		options: {
			inputSourceMap: function (el, sourceFileName) {
				return return el.src[0].replace(/\.js$/, '.js.map');
			}
		}
	}
});

MIT © Sindre Sorhus