Add vendor and .env to make usable

vendor/symfony/var-dumper/Tests/Fixtures/GeneratorDemo.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace Symfony\Component\VarDumper\Tests\Fixtures;
+
+class GeneratorDemo
+{
+    public static function foo()
+    {
+        yield 1;
+    }
+
+    public function baz()
+    {
+        yield from bar();
+    }
+}
+
+function bar()
+{
+    yield from GeneratorDemo::foo();
+}