[BREAKING] ES2015ify and require Node.js 4

.gitattributes

@@ -1 +1,2 @@
 * text=auto
+*.js text eol=lf

gruntfile.js

@@ -1,7 +1,7 @@
 'use strict';
-module.exports = function (grunt) {
+module.exports = grunt => {
 	function log(err, stdout, stderr, cb) {
-		console.log('Directory listing:\n' + stdout);
+		console.log(`Directory listing:\n${stdout}`);
 		cb();
 	}
 
@@ -17,13 +17,13 @@ module.exports = function (grunt) {
 				}
 			},
 			fnCmd: {
-				command: function (version) {
+				command(version) {
 					// `this` is scoped to the grunt instance
 					if (version) {
-						return 'echo grunt-shell version: ' + version;
+						return `echo grunt-shell version: ${version}`;
 					}
 
-					return 'echo grunt version: ' + this.version;
+					return `echo grunt version: ${this.version}`;
 				}
 			},
 			callback: {

package.json

@@ -10,7 +10,7 @@
     "url": "sindresorhus.com"
   },
   "engines": {
-    "node": ">=0.10.0"
+    "node": ">=4"
   },
   "scripts": {
     "test": "xo && grunt"
@@ -31,8 +31,7 @@
   ],
   "dependencies": {
     "chalk": "^1.0.0",
-    "npm-run-path": "^2.0.0",
-    "object-assign": "^4.0.0"
+    "npm-run-path": "^2.0.0"
   },
   "devDependencies": {
     "grunt": "^1.0.1",
@@ -41,5 +40,8 @@
   },
   "peerDependencies": {
     "grunt": ">=0.4.0"
+  },
+  "xo": {
+    "esnext": true
   }
 }

readme.md

@@ -183,7 +183,7 @@ grunt.initConfig({
 ### command
 
 *Required*<br>
-Type: `String` `Function`
+Type: `string` `Function`
 
 Command to run or a function which returns the command. Supports underscore templates.
 
@@ -193,35 +193,35 @@ Command to run or a function which returns the command. Supports underscore temp
 
 ### stdout
 
-Type: `Boolean`<br>
+Type: `boolean`<br>
 Default: `true`
 
 Show stdout in the terminal.
 
 ### stderr
 
-Type: `Boolean`<br>
+Type: `boolean`<br>
 Default: `true`
 
 Show stderr in the terminal.
 
 ### stdin
 
-Type: `Boolean`<br>
+Type: `boolean`<br>
 Default: `true`
 
 Forward the terminal's stdin to the command.
 
 ### failOnError
 
-Type: `Boolean`<br>
+Type: `boolean`<br>
 Default: `true`
 
 Fail task if it encounters an error. Doesn't apply if you specify a `callback`.
 
 ### stdinRawMode
 
-Type: `Boolean`<br>
+Type: `boolean`<br>
 Default: `false`
 
 Set `stdin` to [act as a raw device](http://nodejs.org/api/tty.html#tty_rs_setrawmode_mode).
@@ -236,24 +236,24 @@ Lets you override the default callback with your own.
 
 ### preferLocal
 
-Type: `Boolean`<br>
+Type: `boolean`<br>
 Default: `false`
 
-Execute local binaries by name like [npm run-script](http://blog.keithcirkel.co.uk/how-to-use-npm-as-a-build-tool/).
+Execute local binaries by name like [`$ npm run-script`](http://blog.keithcirkel.co.uk/how-to-use-npm-as-a-build-tool/).
 
 ### execOptions
 
 Type: `Object`
 
-Specify some options to be passed to the [.exec()](http://nodejs.org/api/child_process.html#child_process_child_process_exec_command_options_callback) method:
+Specify some options to be passed to the [.exec()](https://nodejs.org/api/child_process.html#child_process_child_process_exec_command_options_callback) method:
 
-- `cwd` String *Current working directory of the child process*
+- `cwd` string *Current working directory of the child process*
 - `env` Object *Environment key-value pairs*
-- `setsid` Boolean
-- `encoding` String *(Default: 'utf8')*
-- `timeout` Number *(Default: 0)*
-- `maxBuffer` Number *(Default: 200\*1024)*
-- `killSignal` String *(Default: 'SIGTERM')*
+- `setsid` boolean
+- `encoding` string *(Default: `'utf8'`)*
+- `timeout` number *(Default: `0`)*
+- `maxBuffer` number *(Default: `200 * 1024`)*
+- `killSignal` string *(Default: `'SIGTERM'`)*
 
 
 ## License

tasks/shell.js

@@ -1,12 +1,12 @@
 'use strict';
-var exec = require('child_process').exec;
-var chalk = require('chalk');
-var npmRunPath = require('npm-run-path');
+const exec = require('child_process').exec;
+const chalk = require('chalk');
+const npmRunPath = require('npm-run-path');
 
-module.exports = function (grunt) {
+module.exports = grunt => {
 	grunt.registerMultiTask('shell', 'Run shell commands', function () {
-		var cb = this.async();
-		var opts = this.options({
+		const cb = this.async();
+		const opts = this.options({
 			stdout: true,
 			stderr: true,
 			stdin: true,
@@ -18,7 +18,7 @@ module.exports = function (grunt) {
 			}
 		});
 
-		var cmd = typeof this.data === 'string' ? this.data : this.data.command;
+		let cmd = typeof this.data === 'string' ? this.data : this.data.command;
 
 		if (cmd === undefined) {
 			throw new Error('`command` required');
@@ -30,7 +30,7 @@ module.exports = function (grunt) {
 			opts.execOptions.env = npmRunPath.env({env: opts.execOptions.env || process.env});
 		}
 
-		var cp = exec(cmd, opts.execOptions, function (err, stdout, stderr) {
+		const cp = exec(cmd, opts.execOptions, (err, stdout, stderr) => {
 			if (typeof opts.callback === 'function') {
 				opts.callback.call(this, err, stdout, stderr, cb);
 			} else {
@@ -39,11 +39,11 @@ module.exports = function (grunt) {
 				}
 				cb();
 			}
-		}.bind(this));
+		});
 
-		var captureOutput = function (child, output) {
+		const captureOutput = (child, output) => {
 			if (grunt.option('color') === false) {
-				child.on('data', function (data) {
+				child.on('data', data => {
 					output.write(chalk.stripColor(data));
 				});
 			} else {