Merge pull request #622 from MyIgel/controllers

AuthController (login, logout), use templating, replaced gettext, input validation

29 files changed, 971 insertions, 156 deletions

diff --git a/tests/Unit/Controllers/AuthControllerTest.php b/tests/Unit/Controllers/AuthControllerTest.php
index c5349cda..c3d9659c 100644
--- a/tests/Unit/Controllers/AuthControllerTest.php
+++ b/tests/Unit/Controllers/AuthControllerTest.php
@@ -3,40 +3,166 @@
 namespace Engelsystem\Test\Unit\Controllers;
 
 use Engelsystem\Controllers\AuthController;
+use Engelsystem\Helpers\Authenticator;
+use Engelsystem\Http\Exceptions\ValidationException;
+use Engelsystem\Http\Request;
 use Engelsystem\Http\Response;
 use Engelsystem\Http\UrlGeneratorInterface;
+use Engelsystem\Http\Validation\Validator;
+use Engelsystem\Models\User\Settings;
+use Engelsystem\Models\User\User;
+use Engelsystem\Test\Unit\HasDatabase;
+use Illuminate\Support\Collection;
 use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
+use Symfony\Component\HttpFoundation\Session\Session;
 use Symfony\Component\HttpFoundation\Session\SessionInterface;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 class AuthControllerTest extends TestCase
 {
+    use HasDatabase;
+
     /**
      * @covers \Engelsystem\Controllers\AuthController::__construct
-     * @covers \Engelsystem\Controllers\AuthController::logout
+     * @covers \Engelsystem\Controllers\AuthController::login
+     * @covers \Engelsystem\Controllers\AuthController::showLogin
      */
-    public function testLogout()
+    public function testLogin()
     {
         /** @var Response|MockObject $response */
         $response = $this->createMock(Response::class);
         /** @var SessionInterface|MockObject $session */
-        $session = $this->getMockForAbstractClass(SessionInterface::class);
         /** @var UrlGeneratorInterface|MockObject $url */
-        $url = $this->getMockForAbstractClass(UrlGeneratorInterface::class);
+        /** @var Authenticator|MockObject $auth */
+        list(, $session, $url, $auth) = $this->getMocks();
 
         $session->expects($this->once())
-            ->method('invalidate');
+            ->method('get')
+            ->with('errors', [])
+            ->willReturn(['foo' => 'bar']);
+        $response->expects($this->once())
+            ->method('withView')
+            ->with('pages/login')
+            ->willReturn($response);
+
+        $controller = new AuthController($response, $session, $url, $auth);
+        $controller->login();
+    }
+
+    /**
+     * @covers \Engelsystem\Controllers\AuthController::postLogin
+     */
+    public function testPostLogin()
+    {
+        $this->initDatabase();
 
+        $request = new Request();
+        /** @var Response|MockObject $response */
+        $response = $this->createMock(Response::class);
+        /** @var UrlGeneratorInterface|MockObject $url */
+        /** @var Authenticator|MockObject $auth */
+        list(, , $url, $auth) = $this->getMocks();
+        $session = new Session(new MockArraySessionStorage());
+        /** @var Validator|MockObject $validator */
+        $validator = new Validator();
+
+        $user = new User([
+            'name'          => 'foo',
+            'password'      => '',
+            'email'         => '',
+            'api_key'       => '',
+            'last_login_at' => null,
+        ]);
+        $user->forceFill(['id' => 42]);
+        $user->save();
+
+        $settings = new Settings(['language' => 'de_DE', 'theme' => '']);
+        $settings->user()
+            ->associate($user)
+            ->save();
+
+        $auth->expects($this->exactly(2))
+            ->method('authenticate')
+            ->with('foo', 'bar')
+            ->willReturnOnConsecutiveCalls(null, $user);
+
+        $response->expects($this->once())
+            ->method('withView')
+            ->with('pages/login', ['errors' => Collection::make(['auth.not-found']), 'show_password_recovery' => true])
+            ->willReturn($response);
         $response->expects($this->once())
             ->method('redirectTo')
-            ->with('https://foo.bar/');
+            ->with('news')
+            ->willReturn($response);
+
+        // No credentials
+        $controller = new AuthController($response, $session, $url, $auth);
+        $controller->setValidator($validator);
+        try {
+            $controller->postLogin($request);
+            $this->fail('Login without credentials possible');
+        } catch (ValidationException $e) {
+        }
+
+        // Missing password
+        $request = new Request([], ['login' => 'foo']);
+        try {
+            $controller->postLogin($request);
+            $this->fail('Login without password possible');
+        } catch (ValidationException $e) {
+        }
+
+        // No user found
+        $request = new Request([], ['login' => 'foo', 'password' => 'bar']);
+        $controller->postLogin($request);
+        $this->assertEquals([], $session->all());
+
+        // Authenticated user
+        $controller->postLogin($request);
+
+        $this->assertNotNull($user->last_login_at);
+        $this->assertEquals(['user_id' => 42, 'locale' => 'de_DE'], $session->all());
+    }
+
+    /**
+     * @covers \Engelsystem\Controllers\AuthController::logout
+     */
+    public function testLogout()
+    {
+        /** @var Response $response */
+        /** @var SessionInterface|MockObject $session */
+        /** @var UrlGeneratorInterface|MockObject $url */
+        /** @var Authenticator|MockObject $auth */
+        list($response, $session, $url, $auth) = $this->getMocks();
+
+        $session->expects($this->once())
+            ->method('invalidate');
 
         $url->expects($this->once())
             ->method('to')
             ->with('/')
             ->willReturn('https://foo.bar/');
 
-        $controller = new AuthController($response, $session, $url);
-        $controller->logout();
+        $controller = new AuthController($response, $session, $url, $auth);
+        $return = $controller->logout();
+
+        $this->assertEquals(['https://foo.bar/'], $return->getHeader('location'));
+    }
+
+    /**
+     * @return array
+     */
+    protected function getMocks()
+    {
+        $response = new Response();
+        /** @var SessionInterface|MockObject $session */
+        $session = $this->getMockForAbstractClass(SessionInterface::class);
+        /** @var UrlGeneratorInterface|MockObject $url */
+        $url = $this->getMockForAbstractClass(UrlGeneratorInterface::class);
+        /** @var Authenticator|MockObject $auth */
+        $auth = $this->createMock(Authenticator::class);
+
+        return [$response, $session, $url, $auth];
     }
 }
diff --git a/tests/Unit/Controllers/BaseControllerTest.php b/tests/Unit/Controllers/BaseControllerTest.php
index 738b538f..2adc9dc7 100644
--- a/tests/Unit/Controllers/BaseControllerTest.php
+++ b/tests/Unit/Controllers/BaseControllerTest.php
@@ -21,5 +21,7 @@ class BaseControllerTest extends TestCase
                 'dolor',
             ],
         ], $controller->getPermissions());
+
+        $this->assertTrue(method_exists($controller, 'setValidator'));
     }
 }
diff --git a/tests/Unit/Controllers/Metrics/MetricsEngineTest.php b/tests/Unit/Controllers/Metrics/MetricsEngineTest.php
index 38817b36..87a7dc88 100644
--- a/tests/Unit/Controllers/Metrics/MetricsEngineTest.php
+++ b/tests/Unit/Controllers/Metrics/MetricsEngineTest.php
@@ -66,4 +66,15 @@ class MetricsEngineTest extends TestCase
         $this->assertFalse($engine->canRender('/metrics.foo'));
         $this->assertTrue($engine->canRender('/metrics'));
     }
+
+    /**
+     * @covers \Engelsystem\Controllers\Metrics\MetricsEngine::share
+     */
+    public function testShare()
+    {
+        $engine = new MetricsEngine();
+
+        $engine->share('foo', 42);
+        $this->assertEquals('', $engine->get('/metrics'));
+    }
 }
diff --git a/tests/Unit/Controllers/Stub/ControllerImplementation.php b/tests/Unit/Controllers/Stub/ControllerImplementation.php
index 01d9f250..a8bf538c 100644
--- a/tests/Unit/Controllers/Stub/ControllerImplementation.php
+++ b/tests/Unit/Controllers/Stub/ControllerImplementation.php
@@ -14,12 +14,4 @@ class ControllerImplementation extends BaseController
             'dolor',
         ],
     ];
-
-    /**
-     * @param array $permissions
-     */
-    public function setPermissions(array $permissions)
-    {
-        $this->permissions = $permissions;
-    }
 }
diff --git a/tests/Unit/Helpers/AuthenticatorServiceProviderTest.php b/tests/Unit/Helpers/AuthenticatorServiceProviderTest.php
index b1767ebc..ab9b23ec 100644
--- a/tests/Unit/Helpers/AuthenticatorServiceProviderTest.php
+++ b/tests/Unit/Helpers/AuthenticatorServiceProviderTest.php
@@ -3,6 +3,7 @@
 namespace Engelsystem\Test\Unit\Helpers;
 
 use Engelsystem\Application;
+use Engelsystem\Config\Config;
 use Engelsystem\Helpers\Authenticator;
 use Engelsystem\Helpers\AuthenticatorServiceProvider;
 use Engelsystem\Http\Request;
@@ -19,11 +20,19 @@ class AuthenticatorServiceProviderTest extends ServiceProviderTest
         $app = new Application();
         $app->bind(ServerRequestInterface::class, Request::class);
 
+        $config = new Config();
+        $config->set('password_algorithm', PASSWORD_DEFAULT);
+        $app->instance('config', $config);
+
         $serviceProvider = new AuthenticatorServiceProvider($app);
         $serviceProvider->register();
 
         $this->assertInstanceOf(Authenticator::class, $app->get(Authenticator::class));
         $this->assertInstanceOf(Authenticator::class, $app->get('authenticator'));
         $this->assertInstanceOf(Authenticator::class, $app->get('auth'));
+
+        /** @var Authenticator $auth */
+        $auth = $app->get(Authenticator::class);
+        $this->assertEquals(PASSWORD_DEFAULT, $auth->getPasswordAlgorithm());
     }
 }
diff --git a/tests/Unit/Helpers/AuthenticatorTest.php b/tests/Unit/Helpers/AuthenticatorTest.php
index 400278f2..83dc72ad 100644
--- a/tests/Unit/Helpers/AuthenticatorTest.php
+++ b/tests/Unit/Helpers/AuthenticatorTest.php
@@ -4,6 +4,7 @@ namespace Engelsystem\Test\Unit\Helpers;
 
 use Engelsystem\Helpers\Authenticator;
 use Engelsystem\Models\User\User;
+use Engelsystem\Test\Unit\HasDatabase;
 use Engelsystem\Test\Unit\Helpers\Stub\UserModelImplementation;
 use Engelsystem\Test\Unit\ServiceProviderTest;
 use PHPUnit\Framework\MockObject\MockObject;
@@ -12,6 +13,8 @@ use Symfony\Component\HttpFoundation\Session\Session;
 
 class AuthenticatorTest extends ServiceProviderTest
 {
+    use HasDatabase;
+
     /**
      * @covers \Engelsystem\Helpers\Authenticator::__construct(
      * @covers \Engelsystem\Helpers\Authenticator::user
@@ -29,7 +32,7 @@ class AuthenticatorTest extends ServiceProviderTest
 
         $session->expects($this->exactly(3))
             ->method('get')
-            ->with('uid')
+            ->with('user_id')
             ->willReturnOnConsecutiveCalls(
                 null,
                 42,
@@ -114,16 +117,13 @@ class AuthenticatorTest extends ServiceProviderTest
         /** @var User|MockObject $user */
         $user = $this->createMock(User::class);
 
-        $user->expects($this->once())
-            ->method('save');
-
-        $session->expects($this->exactly(2))
+        $session->expects($this->once())
             ->method('get')
-            ->with('uid')
+            ->with('user_id')
             ->willReturn(42);
         $session->expects($this->once())
             ->method('remove')
-            ->with('uid');
+            ->with('user_id');
 
         /** @var Authenticator|MockObject $auth */
         $auth = $this->getMockBuilder(Authenticator::class)
@@ -151,4 +151,115 @@ class AuthenticatorTest extends ServiceProviderTest
         // Permissions cached
         $this->assertTrue($auth->can('bar'));
     }
+
+    /**
+     * @covers \Engelsystem\Helpers\Authenticator::authenticate
+     */
+    public function testAuthenticate()
+    {
+        $this->initDatabase();
+
+        /** @var ServerRequestInterface|MockObject $request */
+        $request = $this->getMockForAbstractClass(ServerRequestInterface::class);
+        /** @var Session|MockObject $session */
+        $session = $this->createMock(Session::class);
+        $userRepository = new User();
+
+        (new User([
+            'name'     => 'lorem',
+            'password' => password_hash('testing', PASSWORD_DEFAULT),
+            'email'    => 'lorem@foo.bar',
+            'api_key'  => '',
+        ]))->save();
+        (new User([
+            'name'     => 'ipsum',
+            'password' => '',
+            'email'    => 'ipsum@foo.bar',
+            'api_key'  => '',
+        ]))->save();
+
+        $auth = new Authenticator($request, $session, $userRepository);
+        $this->assertNull($auth->authenticate('not-existing', 'foo'));
+        $this->assertNull($auth->authenticate('ipsum', 'wrong-password'));
+        $this->assertInstanceOf(User::class, $auth->authenticate('lorem', 'testing'));
+        $this->assertInstanceOf(User::class, $auth->authenticate('lorem@foo.bar', 'testing'));
+    }
+
+    /**
+     * @covers \Engelsystem\Helpers\Authenticator::verifyPassword
+     */
+    public function testVerifyPassword()
+    {
+        $this->initDatabase();
+        $password = password_hash('testing', PASSWORD_ARGON2I);
+        $user = new User([
+            'name'     => 'lorem',
+            'password' => $password,
+            'email'    => 'lorem@foo.bar',
+            'api_key'  => '',
+        ]);
+        $user->save();
+
+        /** @var Authenticator|MockObject $auth */
+        $auth = $this->getMockBuilder(Authenticator::class)
+            ->disableOriginalConstructor()
+            ->setMethods(['setPassword'])
+            ->getMock();
+
+        $auth->expects($this->once())
+            ->method('setPassword')
+            ->with($user, 'testing');
+        $auth->setPasswordAlgorithm(PASSWORD_BCRYPT);
+
+        $this->assertFalse($auth->verifyPassword($user, 'randomStuff'));
+        $this->assertTrue($auth->verifyPassword($user, 'testing'));
+    }
+
+    /**
+     * @covers \Engelsystem\Helpers\Authenticator::setPassword
+     */
+    public function testSetPassword()
+    {
+        $this->initDatabase();
+        $user = new User([
+            'name'     => 'ipsum',
+            'password' => '',
+            'email'    => 'ipsum@foo.bar',
+            'api_key'  => '',
+        ]);
+        $user->save();
+
+        $auth = $this->getAuthenticator();
+        $auth->setPasswordAlgorithm(PASSWORD_ARGON2I);
+
+        $auth->setPassword($user, 'FooBar');
+        $this->assertTrue($user->isClean());
+
+        $this->assertTrue(password_verify('FooBar', $user->password));
+        $this->assertFalse(password_needs_rehash($user->password, PASSWORD_ARGON2I));
+    }
+
+    /**
+     * @covers \Engelsystem\Helpers\Authenticator::setPasswordAlgorithm
+     * @covers \Engelsystem\Helpers\Authenticator::getPasswordAlgorithm
+     */
+    public function testPasswordAlgorithm()
+    {
+        $auth = $this->getAuthenticator();
+
+        $auth->setPasswordAlgorithm(PASSWORD_ARGON2I);
+        $this->assertEquals(PASSWORD_ARGON2I, $auth->getPasswordAlgorithm());
+    }
+
+    /**
+     * @return Authenticator
+     */
+    protected function getAuthenticator()
+    {
+        return new class extends Authenticator
+        {
+            /** @noinspection PhpMissingParentConstructorInspection */
+            public function __construct() { }
+        };
+    }
 }
diff --git a/tests/Unit/Helpers/Translation/Assets/fo_OO/default.mo b/tests/Unit/Helpers/Translation/Assets/fo_OO/default.mo
new file mode 100644
index 00000000..96f1f3ca
--- /dev/null
+++ b/tests/Unit/Helpers/Translation/Assets/fo_OO/default.mo
diff --git a/tests/Unit/Helpers/Translation/Assets/fo_OO/default.po b/tests/Unit/Helpers/Translation/Assets/fo_OO/default.po
new file mode 100644
index 00000000..015bc36d
--- /dev/null
+++ b/tests/Unit/Helpers/Translation/Assets/fo_OO/default.po
@@ -0,0 +1,3 @@
+# Testing content
+msgid "foo.bar"
+msgstr "Foo Bar!"
diff --git a/tests/Unit/Helpers/Translation/GettextTranslatorTest.php b/tests/Unit/Helpers/Translation/GettextTranslatorTest.php
new file mode 100644
index 00000000..825cf5b7
--- /dev/null
+++ b/tests/Unit/Helpers/Translation/GettextTranslatorTest.php
@@ -0,0 +1,67 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Helpers\Translation;
+
+use Engelsystem\Helpers\Translation\GettextTranslator;
+use Engelsystem\Helpers\Translation\TranslationNotFound;
+use Engelsystem\Test\Unit\ServiceProviderTest;
+use Gettext\Translation;
+use Gettext\Translations;
+
+class GettextTranslatorTest extends ServiceProviderTest
+{
+    /**
+     * @covers \Engelsystem\Helpers\Translation\GettextTranslator::assertHasTranslation()
+     */
+    public function testNoTranslation()
+    {
+        $translations = $this->getTranslations();
+
+        $translator = new GettextTranslator();
+        $translator->loadTranslations($translations);
+
+        $this->assertEquals('Translation!', $translator->gettext('test.value'));
+
+        $this->expectException(TranslationNotFound::class);
+        $this->expectExceptionMessage('//foo.bar');
+
+        $translator->gettext('foo.bar');
+    }
+
+    /**
+     * @covers \Engelsystem\Helpers\Translation\GettextTranslator::dpgettext()
+     */
+    public function testDpgettext()
+    {
+        $translations = $this->getTranslations();
+
+        $translator = new GettextTranslator();
+        $translator->loadTranslations($translations);
+
+        $this->assertEquals('Translation!', $translator->dpgettext(null, null, 'test.value'));
+    }
+
+    /**
+     * @covers \Engelsystem\Helpers\Translation\GettextTranslator::dnpgettext()
+     */
+    public function testDnpgettext()
+    {
+        $translations = $this->getTranslations();
+
+        $translator = new GettextTranslator();
+        $translator->loadTranslations($translations);
+
+        $this->assertEquals('Translations!', $translator->dnpgettext(null, null, 'test.value', 'test.values', 2));
+    }
+
+    protected function getTranslations(): Translations
+    {
+        $translations = new Translations();
+        $translations[] =
+            (new Translation(null, 'test.value', 'test.values'))
+                ->setTranslation('Translation!')
+                ->setPluralTranslations(['Translations!']);
+
+        return $translations;
+    }
+}
diff --git a/tests/Unit/Helpers/TranslationServiceProviderTest.php b/tests/Unit/Helpers/Translation/TranslationServiceProviderTest.php
index 41c08aa5..91307bdd 100644
--- a/tests/Unit/Helpers/TranslationServiceProviderTest.php
+++ b/tests/Unit/Helpers/Translation/TranslationServiceProviderTest.php
@@ -1,10 +1,10 @@
 <?php
 
-namespace Engelsystem\Test\Unit\Helpers;
+namespace Engelsystem\Test\Unit\Helpers\Translation;
 
 use Engelsystem\Config\Config;
-use Engelsystem\Helpers\TranslationServiceProvider;
-use Engelsystem\Helpers\Translator;
+use Engelsystem\Helpers\Translation\TranslationServiceProvider;
+use Engelsystem\Helpers\Translation\Translator;
 use Engelsystem\Test\Unit\ServiceProviderTest;
 use PHPUnit\Framework\MockObject\MockObject;
 use Symfony\Component\HttpFoundation\Session\Session;
@@ -12,13 +12,16 @@ use Symfony\Component\HttpFoundation\Session\Session;
 class TranslationServiceProviderTest extends ServiceProviderTest
 {
     /**
-     * @covers \Engelsystem\Helpers\TranslationServiceProvider::register()
+     * @covers \Engelsystem\Helpers\Translation\TranslationServiceProvider::register()
      */
-    public function testRegister()
+    public function testRegister(): void
     {
+        $defaultLocale = 'fo_OO';
+        $locale = 'te_ST.WTF-9';
+        $locales = ['fo_OO' => 'Foo', 'fo_OO.BAR' => 'Foo (Bar)', 'te_ST.WTF-9' => 'WTF\'s Testing?'];
+        $config = new Config(['locales' => $locales, 'default_locale' => $defaultLocale]);
+
         $app = $this->getApp(['make', 'instance', 'get']);
-        /** @var Config|MockObject $config */
-        $config = $this->createMock(Config::class);
         /** @var Session|MockObject $session */
         $session = $this->createMock(Session::class);
         /** @var Translator|MockObject $translator */
@@ -27,31 +30,14 @@ class TranslationServiceProviderTest extends ServiceProviderTest
         /** @var TranslationServiceProvider|MockObject $serviceProvider */
         $serviceProvider = $this->getMockBuilder(TranslationServiceProvider::class)
             ->setConstructorArgs([$app])
-            ->setMethods(['initGettext', 'setLocale'])
+            ->setMethods(['setLocale'])
             ->getMock();
 
-        $serviceProvider->expects($this->once())
-            ->method('initGettext');
-
         $app->expects($this->exactly(2))
             ->method('get')
             ->withConsecutive(['config'], ['session'])
             ->willReturnOnConsecutiveCalls($config, $session);
 
-        $defaultLocale = 'fo_OO';
-        $locale = 'te_ST.WTF-9';
-        $locales = ['fo_OO' => 'Foo', 'fo_OO.BAR' => 'Foo (Bar)', 'te_ST.WTF-9' => 'WTF\'s Testing?'];
-        $config->expects($this->exactly(2))
-            ->method('get')
-            ->withConsecutive(
-                ['locales'],
-                ['default_locale']
-            )
-            ->willReturnOnConsecutiveCalls(
-                $locales,
-                $defaultLocale
-            );
-
         $session->expects($this->once())
             ->method('get')
             ->with('locale', $defaultLocale)
@@ -65,9 +51,11 @@ class TranslationServiceProviderTest extends ServiceProviderTest
             ->with(
                 Translator::class,
                 [
-                    'locale'               => $locale,
-                    'locales'              => $locales,
-                    'localeChangeCallback' => [$serviceProvider, 'setLocale'],
+                    'locale'                => $locale,
+                    'locales'               => $locales,
+                    'fallbackLocale'        => 'en_US',
+                    'getTranslatorCallback' => [$serviceProvider, 'getTranslator'],
+                    'localeChangeCallback'  => [$serviceProvider, 'setLocale'],
                 ]
             )
             ->willReturn($translator);
@@ -81,4 +69,22 @@ class TranslationServiceProviderTest extends ServiceProviderTest
 
         $serviceProvider->register();
     }
+
+    /**
+     * @covers \Engelsystem\Helpers\Translation\TranslationServiceProvider::getTranslator()
+     */
+    public function testGetTranslator(): void
+    {
+        $app = $this->getApp(['get']);
+        $serviceProvider = new TranslationServiceProvider($app);
+
+        $this->setExpects($app, 'get', ['path.lang'], __DIR__ . '/Assets');
+
+        // Get translator
+        $translator = $serviceProvider->getTranslator('fo_OO');
+        $this->assertEquals('Foo Bar!', $translator->gettext('foo.bar'));
+
+        // Retry from cache
+        $serviceProvider->getTranslator('fo_OO');
+    }
 }
diff --git a/tests/Unit/Helpers/Translation/TranslatorTest.php b/tests/Unit/Helpers/Translation/TranslatorTest.php
new file mode 100644
index 00000000..c173209a
--- /dev/null
+++ b/tests/Unit/Helpers/Translation/TranslatorTest.php
@@ -0,0 +1,134 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Helpers\Translation;
+
+use Engelsystem\Helpers\Translation\GettextTranslator;
+use Engelsystem\Helpers\Translation\TranslationNotFound;
+use Engelsystem\Helpers\Translation\Translator;
+use Engelsystem\Test\Unit\ServiceProviderTest;
+use PHPUnit\Framework\MockObject\MockObject;
+use stdClass;
+
+class TranslatorTest extends ServiceProviderTest
+{
+    /**
+     * @covers \Engelsystem\Helpers\Translation\Translator::__construct
+     * @covers \Engelsystem\Helpers\Translation\Translator::getLocale
+     * @covers \Engelsystem\Helpers\Translation\Translator::getLocales
+     * @covers \Engelsystem\Helpers\Translation\Translator::hasLocale
+     * @covers \Engelsystem\Helpers\Translation\Translator::setLocale
+     * @covers \Engelsystem\Helpers\Translation\Translator::setLocales
+     */
+    public function testInit()
+    {
+        $locales = ['te_ST' => 'Tests', 'fo_OO' => 'SomeFOO'];
+        $locale = 'te_ST';
+
+        /** @var callable|MockObject $localeChange */
+        $localeChange = $this->getMockBuilder(stdClass::class)
+            ->setMethods(['__invoke'])
+            ->getMock();
+        $localeChange->expects($this->exactly(2))
+            ->method('__invoke')
+            ->withConsecutive(['te_ST'], ['fo_OO']);
+
+        $translator = new Translator($locale, 'fo_OO', function () { }, $locales, $localeChange);
+
+        $this->assertEquals($locales, $translator->getLocales());
+        $this->assertEquals($locale, $translator->getLocale());
+
+        $translator->setLocale('fo_OO');
+        $this->assertEquals('fo_OO', $translator->getLocale());
+
+        $newLocales = ['lo_RM' => 'Lorem', 'ip_SU-M' => 'Ipsum'];
+        $translator->setLocales($newLocales);
+        $this->assertEquals($newLocales, $translator->getLocales());
+
+        $this->assertTrue($translator->hasLocale('ip_SU-M'));
+        $this->assertFalse($translator->hasLocale('te_ST'));
+    }
+
+    /**
+     * @covers \Engelsystem\Helpers\Translation\Translator::translate
+     */
+    public function testTranslate()
+    {
+        /** @var Translator|MockObject $translator */
+        $translator = $this->getMockBuilder(Translator::class)
+            ->setConstructorArgs(['de_DE', 'en_US', function () { }, ['de_DE' => 'Deutsch']])
+            ->setMethods(['translateText'])
+            ->getMock();
+        $translator->expects($this->exactly(2))
+            ->method('translateText')
+            ->withConsecutive(['gettext', ['Hello!'], []], ['gettext', ['My favourite number is %u!'], [3]])
+            ->willReturnOnConsecutiveCalls('Hallo!', 'Meine Lieblingszahl ist die 3!');
+
+        $return = $translator->translate('Hello!');
+        $this->assertEquals('Hallo!', $return);
+
+        $return = $translator->translate('My favourite number is %u!', [3]);
+        $this->assertEquals('Meine Lieblingszahl ist die 3!', $return);
+    }
+
+    /**
+     * @covers \Engelsystem\Helpers\Translation\Translator::translatePlural
+     */
+    public function testTranslatePlural()
+    {
+        /** @var Translator|MockObject $translator */
+        $translator = $this->getMockBuilder(Translator::class)
+            ->setConstructorArgs(['de_DE', 'en_US', function () { }, ['de_DE' => 'Deutsch']])
+            ->setMethods(['translateText'])
+            ->getMock();
+        $translator->expects($this->once())
+            ->method('translateText')
+            ->with('ngettext', ['%s apple', '%s apples', 2], [2])
+            ->willReturn('2 Äpfel');
+
+        $return = $translator->translatePlural('%s apple', '%s apples', 2, [2]);
+        $this->assertEquals('2 Äpfel', $return);
+    }
+
+    /**
+     * @covers \Engelsystem\Helpers\Translation\Translator::translatePlural
+     * @covers \Engelsystem\Helpers\Translation\Translator::translateText
+     * @covers \Engelsystem\Helpers\Translation\Translator::replaceText
+     */
+    public function testReplaceText()
+    {
+        /** @var GettextTranslator|MockObject $gtt */
+        $gtt = $this->createMock(GettextTranslator::class);
+        /** @var callable|MockObject $getTranslator */
+        $getTranslator = $this->getMockBuilder(stdClass::class)
+            ->setMethods(['__invoke'])
+            ->getMock();
+        $getTranslator->expects($this->exactly(5))
+            ->method('__invoke')
+            ->withConsecutive(['te_ST'], ['fo_OO'], ['te_ST'], ['fo_OO'], ['te_ST'])
+            ->willReturn($gtt);
+
+        $i = 0;
+        $gtt->expects($this->exactly(4))
+            ->method('gettext')
+            ->willReturnCallback(function () use (&$i) {
+                $i++;
+                if ($i != 4) {
+                    throw new TranslationNotFound();
+                }
+
+                return 'Lorem %s???';
+            });
+        $this->setExpects($gtt, 'ngettext', ['foo.barf'], 'Lorem %s!');
+
+        $translator = new Translator('te_ST', 'fo_OO', $getTranslator, ['te_ST' => 'Test', 'fo_OO' => 'Foo']);
+
+        // No translation
+        $this->assertEquals('foo.bar', $translator->translate('foo.bar'));
+
+        // Fallback translation
+        $this->assertEquals('Lorem test2???', $translator->translate('foo.batz', ['test2']));
+
+        // Successful translation
+        $this->assertEquals('Lorem test3!', $translator->translatePlural('foo.barf', 'foo.bar2', 3, ['test3']));
+    }
+}
diff --git a/tests/Unit/Helpers/TranslatorTest.php b/tests/Unit/Helpers/TranslatorTest.php
deleted file mode 100644
index 45ca769b..00000000
--- a/tests/Unit/Helpers/TranslatorTest.php
+++ /dev/null
@@ -1,90 +0,0 @@
-<?php
-
-namespace Engelsystem\Test\Unit\Helpers;
-
-use Engelsystem\Helpers\Translator;
-use Engelsystem\Test\Unit\ServiceProviderTest;
-use PHPUnit\Framework\MockObject\MockObject;
-use stdClass;
-
-class TranslatorTest extends ServiceProviderTest
-{
-    /**
-     * @covers \Engelsystem\Helpers\Translator::__construct
-     * @covers \Engelsystem\Helpers\Translator::getLocale
-     * @covers \Engelsystem\Helpers\Translator::getLocales
-     * @covers \Engelsystem\Helpers\Translator::hasLocale
-     * @covers \Engelsystem\Helpers\Translator::setLocale
-     * @covers \Engelsystem\Helpers\Translator::setLocales
-     */
-    public function testInit()
-    {
-        $locales = ['te_ST.ER-01' => 'Tests', 'fo_OO' => 'SomeFOO'];
-        $locale = 'te_ST.ER-01';
-
-        /** @var callable|MockObject $callable */
-        $callable = $this->getMockBuilder(stdClass::class)
-            ->setMethods(['__invoke'])
-            ->getMock();
-        $callable->expects($this->exactly(2))
-            ->method('__invoke')
-            ->withConsecutive(['te_ST.ER-01'], ['fo_OO']);
-
-        $translator = new Translator($locale, $locales, $callable);
-
-        $this->assertEquals($locales, $translator->getLocales());
-        $this->assertEquals($locale, $translator->getLocale());
-
-        $translator->setLocale('fo_OO');
-        $this->assertEquals('fo_OO', $translator->getLocale());
-
-        $newLocales = ['lo_RM' => 'Lorem', 'ip_SU-M' => 'Ipsum'];
-        $translator->setLocales($newLocales);
-        $this->assertEquals($newLocales, $translator->getLocales());
-
-        $this->assertTrue($translator->hasLocale('ip_SU-M'));
-        $this->assertFalse($translator->hasLocale('te_ST.ER-01'));
-    }
-
-    /**
-     * @covers \Engelsystem\Helpers\Translator::replaceText
-     * @covers \Engelsystem\Helpers\Translator::translate
-     */
-    public function testTranslate()
-    {
-        /** @var Translator|MockObject $translator */
-        $translator = $this->getMockBuilder(Translator::class)
-            ->setConstructorArgs(['de_DE.UTF-8', ['de_DE.UTF-8' => 'Deutsch']])
-            ->setMethods(['translateGettext'])
-            ->getMock();
-        $translator->expects($this->exactly(2))
-            ->method('translateGettext')
-            ->withConsecutive(['Hello!'], ['My favourite number is %u!'])
-            ->willReturnOnConsecutiveCalls('Hallo!', 'Meine Lieblingszahl ist die %u!');
-
-        $return = $translator->translate('Hello!');
-        $this->assertEquals('Hallo!', $return);
-
-        $return = $translator->translate('My favourite number is %u!', [3]);
-        $this->assertEquals('Meine Lieblingszahl ist die 3!', $return);
-    }
-
-    /**
-     * @covers \Engelsystem\Helpers\Translator::translatePlural
-     */
-    public function testTranslatePlural()
-    {
-        /** @var Translator|MockObject $translator */
-        $translator = $this->getMockBuilder(Translator::class)
-            ->setConstructorArgs(['de_DE.UTF-8', ['de_DE.UTF-8' => 'Deutsch']])
-            ->setMethods(['translateGettextPlural'])
-            ->getMock();
-        $translator->expects($this->once())
-            ->method('translateGettextPlural')
-            ->with('%s apple', '%s apples', 2)
-            ->willReturn('2 Äpfel');
-
-        $return = $translator->translatePlural('%s apple', '%s apples', 2, [2]);
-        $this->assertEquals('2 Äpfel', $return);
-    }
-}
diff --git a/tests/Unit/HelpersTest.php b/tests/Unit/HelpersTest.php
index ad677cb3..09362a90 100644
--- a/tests/Unit/HelpersTest.php
+++ b/tests/Unit/HelpersTest.php
@@ -6,7 +6,7 @@ use Engelsystem\Application;
 use Engelsystem\Config\Config;
 use Engelsystem\Container\Container;
 use Engelsystem\Helpers\Authenticator;
-use Engelsystem\Helpers\Translator;
+use Engelsystem\Helpers\Translation\Translator;
 use Engelsystem\Http\Request;
 use Engelsystem\Http\Response;
 use Engelsystem\Http\UrlGeneratorInterface;
diff --git a/tests/Unit/Http/Exceptions/ValidationExceptionTest.php b/tests/Unit/Http/Exceptions/ValidationExceptionTest.php
new file mode 100644
index 00000000..c5a38b5a
--- /dev/null
+++ b/tests/Unit/Http/Exceptions/ValidationExceptionTest.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Http\Exceptions;
+
+use Engelsystem\Http\Exceptions\ValidationException;
+use Engelsystem\Http\Validation\Validator;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+
+class ValidationExceptionTest extends TestCase
+{
+    /**
+     * @covers \Engelsystem\Http\Exceptions\ValidationException::__construct
+     * @covers \Engelsystem\Http\Exceptions\ValidationException::getValidator
+     */
+    public function testConstruct()
+    {
+        /** @var Validator|MockObject $validator */
+        $validator = $this->createMock(Validator::class);
+
+        $exception = new ValidationException($validator);
+
+        $this->assertEquals($validator, $exception->getValidator());
+    }
+}
diff --git a/tests/Unit/Http/UrlGeneratorServiceProviderTest.php b/tests/Unit/Http/UrlGeneratorServiceProviderTest.php
index 61bf3e7c..6d18f160 100644
--- a/tests/Unit/Http/UrlGeneratorServiceProviderTest.php
+++ b/tests/Unit/Http/UrlGeneratorServiceProviderTest.php
@@ -19,7 +19,7 @@ class UrlGeneratorServiceProviderTest extends ServiceProviderTest
         $urlGenerator = $this->getMockBuilder(UrlGenerator::class)
             ->getMock();
 
-        $app = $this->getApp();
+        $app = $this->getApp(['make', 'instance', 'bind']);
 
         $this->setExpects($app, 'make', [UrlGenerator::class], $urlGenerator);
         $app->expects($this->exactly(2))
@@ -29,6 +29,9 @@ class UrlGeneratorServiceProviderTest extends ServiceProviderTest
                 ['http.urlGenerator', $urlGenerator],
                 [UrlGeneratorInterface::class, $urlGenerator]
             );
+        $app->expects($this->once())
+            ->method('bind')
+            ->with(UrlGeneratorInterface::class, UrlGenerator::class);
 
         $serviceProvider = new UrlGeneratorServiceProvider($app);
         $serviceProvider->register();
diff --git a/tests/Unit/Http/Validation/Rules/InTest.php b/tests/Unit/Http/Validation/Rules/InTest.php
new file mode 100644
index 00000000..e5688d90
--- /dev/null
+++ b/tests/Unit/Http/Validation/Rules/InTest.php
@@ -0,0 +1,19 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Http\Validation\Rules;
+
+use Engelsystem\Http\Validation\Rules\In;
+use Engelsystem\Test\Unit\TestCase;
+
+class InTest extends TestCase
+{
+    /**
+     * @covers \Engelsystem\Http\Validation\Rules\In::__construct
+     */
+    public function testConstruct()
+    {
+        $rule = new In('foo,bar');
+
+        $this->assertEquals(['foo', 'bar'], $rule->haystack);
+    }
+}
diff --git a/tests/Unit/Http/Validation/Rules/NotInTest.php b/tests/Unit/Http/Validation/Rules/NotInTest.php
new file mode 100644
index 00000000..9be12336
--- /dev/null
+++ b/tests/Unit/Http/Validation/Rules/NotInTest.php
@@ -0,0 +1,20 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Http\Validation\Rules;
+
+use Engelsystem\Http\Validation\Rules\NotIn;
+use Engelsystem\Test\Unit\TestCase;
+
+class NotInTest extends TestCase
+{
+    /**
+     * @covers \Engelsystem\Http\Validation\Rules\NotIn::validate
+     */
+    public function testConstruct()
+    {
+        $rule = new NotIn('foo,bar');
+
+        $this->assertTrue($rule->validate('lorem'));
+        $this->assertFalse($rule->validate('foo'));
+    }
+}
diff --git a/tests/Unit/Http/Validation/Stub/ValidatesRequestImplementation.php b/tests/Unit/Http/Validation/Stub/ValidatesRequestImplementation.php
new file mode 100644
index 00000000..772b1dc9
--- /dev/null
+++ b/tests/Unit/Http/Validation/Stub/ValidatesRequestImplementation.php
@@ -0,0 +1,27 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Http\Validation\Stub;
+
+use Engelsystem\Controllers\BaseController;
+use Engelsystem\Http\Request;
+
+class ValidatesRequestImplementation extends BaseController
+{
+    /**
+     * @param Request $request
+     * @param array   $rules
+     * @return array
+     */
+    public function validateData(Request $request, array $rules)
+    {
+        return $this->validate($request, $rules);
+    }
+
+    /**
+     * @return bool
+     */
+    public function hasValidator()
+    {
+        return !is_null($this->validator);
+    }
+}
diff --git a/tests/Unit/Http/Validation/ValidatesRequestTest.php b/tests/Unit/Http/Validation/ValidatesRequestTest.php
new file mode 100644
index 00000000..8011bd03
--- /dev/null
+++ b/tests/Unit/Http/Validation/ValidatesRequestTest.php
@@ -0,0 +1,46 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Http\Validation;
+
+use Engelsystem\Http\Exceptions\ValidationException;
+use Engelsystem\Http\Request;
+use Engelsystem\Http\Validation\Validator;
+use Engelsystem\Test\Unit\Http\Validation\Stub\ValidatesRequestImplementation;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+
+class ValidatesRequestTest extends TestCase
+{
+    /**
+     * @covers \Engelsystem\Http\Validation\ValidatesRequest::validate
+     * @covers \Engelsystem\Http\Validation\ValidatesRequest::setValidator
+     */
+    public function testValidate()
+    {
+        /** @var Validator|MockObject $validator */
+        $validator = $this->createMock(Validator::class);
+        $validator->expects($this->exactly(2))
+            ->method('validate')
+            ->withConsecutive(
+                [['foo' => 'bar'], ['foo' => 'required']],
+                [[], ['foo' => 'required']]
+            )
+            ->willReturnOnConsecutiveCalls(
+                true,
+                false
+            );
+        $validator->expects($this->once())
+            ->method('getData')
+            ->willReturn(['foo' => 'bar']);
+
+        $implementation = new ValidatesRequestImplementation();
+        $implementation->setValidator($validator);
+
+        $return = $implementation->validateData(new Request([], ['foo' => 'bar']), ['foo' => 'required']);
+
+        $this->assertEquals(['foo' => 'bar'], $return);
+
+        $this->expectException(ValidationException::class);
+        $implementation->validateData(new Request([], []), ['foo' => 'required']);
+    }
+}
diff --git a/tests/Unit/Http/Validation/ValidationServiceProviderTest.php b/tests/Unit/Http/Validation/ValidationServiceProviderTest.php
new file mode 100644
index 00000000..969f4351
--- /dev/null
+++ b/tests/Unit/Http/Validation/ValidationServiceProviderTest.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Http\Validation;
+
+use Engelsystem\Application;
+use Engelsystem\Http\Validation\ValidationServiceProvider;
+use Engelsystem\Http\Validation\Validator;
+use Engelsystem\Test\Unit\Http\Validation\Stub\ValidatesRequestImplementation;
+use Engelsystem\Test\Unit\ServiceProviderTest;
+use stdClass;
+
+class ValidationServiceProviderTest extends ServiceProviderTest
+{
+    /**
+     * @covers \Engelsystem\Http\Validation\ValidationServiceProvider::register
+     */
+    public function testRegister()
+    {
+        $app = new Application();
+
+        $serviceProvider = new ValidationServiceProvider($app);
+        $serviceProvider->register();
+
+        $this->assertTrue($app->has(Validator::class));
+        $this->assertTrue($app->has('validator'));
+
+        /** @var ValidatesRequestImplementation $validatesRequest */
+        $validatesRequest = $app->make(ValidatesRequestImplementation::class);
+        $this->assertTrue($validatesRequest->hasValidator());
+
+        // Test afterResolving early return
+        $app->make(stdClass::class);
+    }
+}
diff --git a/tests/Unit/Http/Validation/ValidatorTest.php b/tests/Unit/Http/Validation/ValidatorTest.php
new file mode 100644
index 00000000..450e5d4e
--- /dev/null
+++ b/tests/Unit/Http/Validation/ValidatorTest.php
@@ -0,0 +1,142 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Http\Validation;
+
+use Engelsystem\Http\Validation\Validator;
+use InvalidArgumentException;
+use PHPUnit\Framework\TestCase;
+
+class ValidatorTest extends TestCase
+{
+    /**
+     * @covers \Engelsystem\Http\Validation\Validator::validate
+     * @covers \Engelsystem\Http\Validation\Validator::getData
+     * @covers \Engelsystem\Http\Validation\Validator::getErrors
+     */
+    public function testValidate()
+    {
+        $val = new Validator();
+
+        $this->assertTrue($val->validate(
+            ['foo' => 'bar', 'lorem' => 'on', 'dolor' => 'bla'],
+            ['lorem' => 'accepted']
+        ));
+        $this->assertEquals(['lorem' => 'on'], $val->getData());
+
+        $this->assertFalse($val->validate(
+            [],
+            ['lorem' => 'required|min:3']
+        ));
+        $this->assertEquals(
+            ['lorem' => ['validation.lorem.required', 'validation.lorem.min']],
+            $val->getErrors()
+        );
+    }
+
+    /**
+     * @covers \Engelsystem\Http\Validation\Validator::validate
+     */
+    public function testValidateChaining()
+    {
+        $val = new Validator();
+
+        $this->assertTrue($val->validate(
+            ['lorem' => 10],
+            ['lorem' => 'required|min:3|max:10']
+        ));
+        $this->assertTrue($val->validate(
+            ['lorem' => 3],
+            ['lorem' => 'required|min:3|max:10']
+        ));
+
+        $this->assertFalse($val->validate(
+            ['lorem' => 2],
+            ['lorem' => 'required|min:3|max:10']
+        ));
+        $this->assertFalse($val->validate(
+            ['lorem' => 42],
+            ['lorem' => 'required|min:3|max:10']
+        ));
+    }
+
+    /**
+     * @covers \Engelsystem\Http\Validation\Validator::validate
+     */
+    public function testValidateNotImplemented()
+    {
+        $val = new Validator();
+
+        $this->expectException(InvalidArgumentException::class);
+
+        $val->validate(
+            ['lorem' => 'bar'],
+            ['foo' => 'never_implemented']
+        );
+    }
+
+    /**
+     * @covers \Engelsystem\Http\Validation\Validator::map
+     * @covers \Engelsystem\Http\Validation\Validator::mapBack
+     */
+    public function testValidateMapping()
+    {
+        $val = new Validator();
+
+        $this->assertTrue($val->validate(
+            ['foo' => 'bar'],
+            ['foo' => 'required']
+        ));
+        $this->assertTrue($val->validate(
+            ['foo' => '0'],
+            ['foo' => 'int']
+        ));
+        $this->assertTrue($val->validate(
+            ['foo' => 'on'],
+            ['foo' => 'accepted']
+        ));
+
+        $this->assertFalse($val->validate(
+            [],
+            ['lorem' => 'required']
+        ));
+        $this->assertEquals(
+            ['lorem' => ['validation.lorem.required']],
+            $val->getErrors()
+        );
+    }
+
+    /**
+     * @covers \Engelsystem\Http\Validation\Validator::validate
+     */
+    public function testValidateNesting()
+    {
+        $val = new Validator();
+
+        $this->assertTrue($val->validate(
+            [],
+            ['foo' => 'not|required']
+        ));
+
+        $this->assertTrue($val->validate(
+            ['foo' => 'foo'],
+            ['foo' => 'not|int']
+        ));
+        $this->assertFalse($val->validate(
+            ['foo' => 1],
+            ['foo' => 'not|int']
+        ));
+
+        $this->assertTrue($val->validate(
+            [],
+            ['foo' => 'optional|int']
+        ));
+        $this->assertTrue($val->validate(
+            ['foo' => '33'],
+            ['foo' => 'optional|int']
+        ));
+        $this->assertFalse($val->validate(
+            ['foo' => 'T'],
+            ['foo' => 'optional|int']
+        ));
+    }
+}
diff --git a/tests/Unit/Middleware/ErrorHandlerTest.php b/tests/Unit/Middleware/ErrorHandlerTest.php
index 6c37b651..a9fdd71a 100644
--- a/tests/Unit/Middleware/ErrorHandlerTest.php
+++ b/tests/Unit/Middleware/ErrorHandlerTest.php
@@ -2,14 +2,23 @@
 
 namespace Engelsystem\Test\Unit\Middleware;
 
+use Engelsystem\Application;
 use Engelsystem\Http\Exceptions\HttpException;
+use Engelsystem\Http\Exceptions\ValidationException;
+use Engelsystem\Http\Psr7ServiceProvider;
+use Engelsystem\Http\Request;
 use Engelsystem\Http\Response;
+use Engelsystem\Http\ResponseServiceProvider;
+use Engelsystem\Http\Validation\Validator;
 use Engelsystem\Middleware\ErrorHandler;
 use Engelsystem\Test\Unit\Middleware\Stub\ReturnResponseMiddlewareHandler;
 use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Twig_LoaderInterface as TwigLoader;
 
 class ErrorHandlerTest extends TestCase
@@ -104,7 +113,7 @@ class ErrorHandlerTest extends TestCase
     /**
      * @covers \Engelsystem\Middleware\ErrorHandler::process
      */
-    public function testProcessException()
+    public function testProcessHttpException()
     {
         /** @var ServerRequestInterface|MockObject $request */
         $request = $this->createMock(ServerRequestInterface::class);
@@ -146,6 +155,67 @@ class ErrorHandlerTest extends TestCase
 
     /**
      * @covers \Engelsystem\Middleware\ErrorHandler::process
+     * @covers \Engelsystem\Middleware\ErrorHandler::getPreviousUrl
+     */
+    public function testProcessValidationException()
+    {
+        /** @var TwigLoader|MockObject $twigLoader */
+        $twigLoader = $this->createMock(TwigLoader::class);
+        $handler = $this->getMockForAbstractClass(RequestHandlerInterface::class);
+        $validator = $this->createMock(Validator::class);
+
+        $handler->expects($this->exactly(2))
+            ->method('handle')
+            ->willReturnCallback(function () use ($validator) {
+                throw new ValidationException($validator);
+            });
+
+        $validator->expects($this->exactly(2))
+            ->method('getErrors')
+            ->willReturn(['foo' => ['validation.foo.numeric']]);
+
+        $session = new Session(new MockArraySessionStorage());
+        $session->set('errors', ['validation' => ['foo' => ['validation.foo.required']]]);
+        $request = Request::create(
+            '/foo/bar',
+            'POST',
+            ['foo' => 'bar', 'password' => 'Test123', 'password_confirmation' => 'Test1234']
+        );
+        $request->setSession($session);
+
+        /** @var Application $app */
+        $app = app();
+        (new ResponseServiceProvider($app))->register();
+        (new Psr7ServiceProvider($app))->register();
+
+        $errorHandler = new ErrorHandler($twigLoader);
+
+        $return = $errorHandler->process($request, $handler);
+
+        $this->assertEquals(302, $return->getStatusCode());
+        $this->assertEquals('/', $return->getHeaderLine('location'));
+        $this->assertEquals([
+            'errors'    => [
+                'validation' => [
+                    'foo' => [
+                        'validation.foo.required',
+                        'validation.foo.numeric',
+                    ],
+                ],
+            ],
+            'form-data' => [
+                'foo' => 'bar',
+            ],
+        ], $session->all());
+
+        $request = $request->withAddedHeader('referer', '/foo/batz');
+        $return = $errorHandler->process($request, $handler);
+
+        $this->assertEquals('/foo/batz', $return->getHeaderLine('location'));
+    }
+
+    /**
+     * @covers \Engelsystem\Middleware\ErrorHandler::process
      */
     public function testProcessContentTypeSniffer()
     {
@@ -153,7 +223,7 @@ class ErrorHandlerTest extends TestCase
         $request = $this->createMock(ServerRequestInterface::class);
         /** @var TwigLoader|MockObject $twigLoader */
         $twigLoader = $this->createMock(TwigLoader::class);
-        $response = new Response('<!DOCTYPE html><html><body><h1>Hi!</h1></body></html>', 500);
+        $response = new Response('<!DOCTYPE html><html lang="en"><body><h1>Hi!</h1></body></html>', 500);
         $returnResponseHandler = new ReturnResponseMiddlewareHandler($response);
 
         /** @var ErrorHandler|MockObject $errorHandler */
diff --git a/tests/Unit/Middleware/LegacyMiddlewareTest.php b/tests/Unit/Middleware/LegacyMiddlewareTest.php
index f14a38ed..cce7371a 100644
--- a/tests/Unit/Middleware/LegacyMiddlewareTest.php
+++ b/tests/Unit/Middleware/LegacyMiddlewareTest.php
@@ -3,7 +3,7 @@
 namespace Engelsystem\Test\Unit\Middleware;
 
 use Engelsystem\Helpers\Authenticator;
-use Engelsystem\Helpers\Translator;
+use Engelsystem\Helpers\Translation\Translator;
 use Engelsystem\Http\Request;
 use Engelsystem\Middleware\LegacyMiddleware;
 use PHPUnit\Framework\MockObject\MockObject;
diff --git a/tests/Unit/Middleware/SetLocaleTest.php b/tests/Unit/Middleware/SetLocaleTest.php
index dc68d83a..a586f6b7 100644
--- a/tests/Unit/Middleware/SetLocaleTest.php
+++ b/tests/Unit/Middleware/SetLocaleTest.php
@@ -2,7 +2,7 @@
 
 namespace Engelsystem\Test\Unit\Middleware;
 
-use Engelsystem\Helpers\Translator;
+use Engelsystem\Helpers\Translation\Translator;
 use Engelsystem\Middleware\SetLocale;
 use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
diff --git a/tests/Unit/Renderer/EngineTest.php b/tests/Unit/Renderer/EngineTest.php
new file mode 100644
index 00000000..659d85c5
--- /dev/null
+++ b/tests/Unit/Renderer/EngineTest.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Renderer;
+
+use Engelsystem\Test\Unit\Renderer\Stub\EngineImplementation;
+use PHPUnit\Framework\TestCase;
+
+class EngineTest extends TestCase
+{
+    /**
+     * @covers \Engelsystem\Renderer\Engine::share
+     */
+    public function testShare()
+    {
+        $engine = new EngineImplementation();
+        $engine->share(['foo' => ['bar' => 'baz', 'lorem' => 'ipsum']]);
+        $engine->share(['foo' => ['lorem' => 'dolor']]);
+        $engine->share('key', 'value');
+
+        $this->assertEquals(
+            ['foo' => ['bar' => 'baz', 'lorem' => 'dolor'], 'key' => 'value'],
+            $engine->getSharedData()
+        );
+    }
+}
diff --git a/tests/Unit/Renderer/HtmlEngineTest.php b/tests/Unit/Renderer/HtmlEngineTest.php
index 4a31e4bc..f76e7528 100644
--- a/tests/Unit/Renderer/HtmlEngineTest.php
+++ b/tests/Unit/Renderer/HtmlEngineTest.php
@@ -16,11 +16,12 @@ class HtmlEngineTest extends TestCase
     public function testGet()
     {
         $engine = new HtmlEngine();
+        $engine->share('shared_data', 'tester');
 
-        $file = $this->createTempFile('<div>%main_content%</div>');
+        $file = $this->createTempFile('<div>%main_content% is a %shared_data%</div>');
 
         $data = $engine->get($file, ['main_content' => 'Lorem ipsum dolor sit']);
-        $this->assertEquals('<div>Lorem ipsum dolor sit</div>', $data);
+        $this->assertEquals('<div>Lorem ipsum dolor sit is a tester</div>', $data);
     }
 
     /**
diff --git a/tests/Unit/Renderer/Stub/EngineImplementation.php b/tests/Unit/Renderer/Stub/EngineImplementation.php
new file mode 100644
index 00000000..fc436569
--- /dev/null
+++ b/tests/Unit/Renderer/Stub/EngineImplementation.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace Engelsystem\Test\Unit\Renderer\Stub;
+
+use Engelsystem\Renderer\Engine;
+
+class EngineImplementation extends Engine
+{
+    /**
+     * @inheritdoc
+     */
+    public function get(string $path, array $data = []): string
+    {
+        return '';
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function canRender(string $path): bool
+    {
+        return true;
+    }
+
+    /**
+     * @return array
+     */
+    public function getSharedData(): array
+    {
+        return $this->sharedData;
+    }
+}
diff --git a/tests/Unit/Renderer/Twig/Extensions/TranslationTest.php b/tests/Unit/Renderer/Twig/Extensions/TranslationTest.php
index 18705683..0b055c44 100644
--- a/tests/Unit/Renderer/Twig/Extensions/TranslationTest.php
+++ b/tests/Unit/Renderer/Twig/Extensions/TranslationTest.php
@@ -2,7 +2,7 @@
 
 namespace Engelsystem\Test\Unit\Renderer\Twig\Extensions;
 
-use Engelsystem\Helpers\Translator;
+use Engelsystem\Helpers\Translation\Translator;
 use Engelsystem\Renderer\Twig\Extensions\Translation;
 use PHPUnit\Framework\MockObject\MockObject;
 use Twig_Extensions_TokenParser_Trans as TranslationTokenParser;
diff --git a/tests/Unit/Renderer/TwigEngineTest.php b/tests/Unit/Renderer/TwigEngineTest.php
index 9d0618f1..5e5e59d9 100644
--- a/tests/Unit/Renderer/TwigEngineTest.php
+++ b/tests/Unit/Renderer/TwigEngineTest.php
@@ -20,16 +20,16 @@ class TwigEngineTest extends TestCase
         $twig = $this->createMock(Twig::class);
 
         $path = 'foo.twig';
-        $data = ['lorem' => 'ipsum'];
-
         $twig->expects($this->once())
             ->method('render')
-            ->with($path, $data)
-            ->willReturn('LoremIpsum!');
+            ->with($path, ['lorem' => 'ipsum', 'shared' => 'data'])
+            ->willReturn('LoremIpsum data!');
 
         $engine = new TwigEngine($twig);
-        $return = $engine->get($path, $data);
-        $this->assertEquals('LoremIpsum!', $return);
+        $engine->share('shared', 'data');
+
+        $return = $engine->get($path, ['lorem' => 'ipsum']);
+        $this->assertEquals('LoremIpsum data!', $return);
     }