Add functional test

Author: clue

tests/FunctionalResolverTest.php

@@ -0,0 +1,59 @@
+<?php
+
+namespace React\Tests\Dns;
+
+use React\EventLoop\Factory as LoopFactory;
+use React\Dns\Resolver\Resolver;
+use React\Dns\Resolver\Factory;
+
+class FunctionalTest extends \PHPUnit_Framework_TestCase
+{
+    public function setUp()
+    {
+        $this->loop = LoopFactory::create();
+
+        $factory = new Factory();
+        $this->resolver = $factory->create('8.8.8.8', $this->loop);
+    }
+
+    public function testResolveGoogleResolves()
+    {
+        $promise = $this->resolver->resolve('google.com');
+        $promise->then($this->expectCallableOnce(), $this->expectCallableNever());
+
+        $this->loop->run();
+    }
+
+    public function testResolveInvalidRejects()
+    {
+        $promise = $this->resolver->resolve('example.invalid');
+        $promise->then($this->expectCallableNever(), $this->expectCallableOnce());
+
+        $this->loop->run();
+    }
+
+    protected function expectCallableOnce()
+    {
+        $mock = $this->createCallableMock();
+        $mock
+            ->expects($this->once())
+            ->method('__invoke');
+
+        return $mock;
+    }
+
+    protected function expectCallableNever()
+    {
+        $mock = $this->createCallableMock();
+        $mock
+            ->expects($this->never())
+            ->method('__invoke');
+
+        return $mock;
+    }
+
+    protected function createCallableMock()
+    {
+        return $this->getMock('React\Tests\Dns\CallableStub');
+    }
+}