Added tests for resource server middleware

tests/ResourceServerTest.php

@@ -0,0 +1,28 @@
+<?php
+
+
+namespace LeagueTests;
+
+
+use League\OAuth2\Server\Exception\OAuthServerException;
+use League\OAuth2\Server\Repositories\AccessTokenRepositoryInterface;
+use League\OAuth2\Server\ResourceServer;
+use Zend\Diactoros\ServerRequestFactory;
+
+class ResourceServerTest extends \PHPUnit_Framework_TestCase
+{
+    public function testValidateAuthenticatedRequest()
+    {
+        $server = new ResourceServer(
+            $this->getMock(AccessTokenRepositoryInterface::class),
+            'file://' . __DIR__ . '/Stubs/public.key'
+        );
+
+        try {
+            $server->validateAuthenticatedRequest(ServerRequestFactory::fromGlobals());
+        } catch (OAuthServerException $e) {
+            $this->assertEquals('Missing "Authorization" header', $e->getHint());
+        }
+    }
+
+}