Create register.js (#79)

README.md

@@ -83,6 +83,12 @@ import browserEnv from 'browser-env';
 browserEnv();
 ```
 
+`browser-env` can also be preloaded at node startup as:
+
+```sh
+node -r browser-env/register test.js
+```
+
 ## Related
 
 - [`window`](https://github.com/lukechilds/window) - Exports a jsdom window object

register.js

@@ -0,0 +1,4 @@
+'use strict';
+const browserEnv = require('.');
+
+browserEnv();

test/register-entry-must-preload-env.js

@@ -0,0 +1,11 @@
+import { spawnSync } from 'child_process';
+import test from 'ava';
+
+test(t => {
+	const { stdout } = spawnSync('node', [
+		'-r', '../register',
+		'--eval', 'console.log(typeof window)'
+	]);
+
+	t.not(stdout.toString(), 'undefined');
+});