diff --git a/tests/unit/MysqlTestCase.php b/tests/unit/MysqlTestCase.php
deleted file mode 100644
index 3c16e03..0000000
--- a/tests/unit/MysqlTestCase.php
+++ /dev/null
@@ -1,37 +0,0 @@
-<?php
-
-namespace yiiunit;
-
-class MysqlTestCase extends TestCase
-{
-	protected function setUp()
-	{
-		parent::setUp();
-		if (!extension_loaded('pdo') || !extension_loaded('pdo_mysql')) {
-			$this->markTestSkipped('pdo and pdo_mysql extensions are required.');
-		}
-	}
-
-	/**
-	 * @param bool $reset whether to clean up the test database
-	 * @return \yii\db\Connection
-	 */
-	public function getConnection($reset = true)
-	{
-		$params = $this->getParam('mysql');
-		$db = new \yii\db\Connection;
-		$db->dsn = $params['dsn'];
-		$db->username = $params['username'];
-		$db->password = $params['password'];
-		if ($reset) {
-			$db->open();
-			$lines = explode(';', file_get_contents($params['fixture']));
-			foreach ($lines as $line) {
-				if (trim($line) !== '') {
-					$db->pdo->exec($line);
-				}
-			}
-		}
-		return $db;
-	}
-}
diff --git a/tests/unit/TestCase.php b/tests/unit/TestCase.php
index 44cb238..479f85d 100644
--- a/tests/unit/TestCase.php
+++ b/tests/unit/TestCase.php
@@ -5,7 +5,7 @@ namespace yiiunit;
 /**
  * This is the base class for all yii framework unit tests.
  */
-class TestCase extends \yii\test\TestCase
+abstract class TestCase extends \yii\test\TestCase
 {
 	public static $params;
 
diff --git a/tests/unit/framework/caching/ApcCacheTest.php b/tests/unit/framework/caching/ApcCacheTest.php
index c059554..17bcb6e 100644
--- a/tests/unit/framework/caching/ApcCacheTest.php
+++ b/tests/unit/framework/caching/ApcCacheTest.php
@@ -1,12 +1,11 @@
 <?php
 namespace yiiunit\framework\caching;
 use yii\caching\ApcCache;
-use yiiunit\TestCase;
 
 /**
  * Class for testing APC cache backend
  */
-class ApcCacheTest extends CacheTest
+class ApcCacheTest extends CacheTestCase
 {
 	private $_cacheInstance = null;
 
diff --git a/tests/unit/framework/caching/CacheTest.php b/tests/unit/framework/caching/CacheTestCase.php
similarity index 97%
rename from tests/unit/framework/caching/CacheTest.php
rename to tests/unit/framework/caching/CacheTestCase.php
index 4b34de0..5808fa0 100644
--- a/tests/unit/framework/caching/CacheTest.php
+++ b/tests/unit/framework/caching/CacheTestCase.php
@@ -7,7 +7,7 @@ namespace yii\caching;
  * @return int
  */
 function time() {
-	return \yiiunit\framework\caching\CacheTest::$time ?: \time();
+	return \yiiunit\framework\caching\CacheTestCase::$time ?: \time();
 }
 
 namespace yiiunit\framework\caching;
@@ -18,7 +18,7 @@ use yii\caching\Cache;
 /**
  * Base class for testing cache backends
  */
-abstract class CacheTest extends TestCase
+abstract class CacheTestCase extends TestCase
 {
 	/**
 	 * @var int virtual time to be returned by mocked time() function.
diff --git a/tests/unit/framework/caching/DbCacheTest.php b/tests/unit/framework/caching/DbCacheTest.php
index f5bbba5..3a26595 100644
--- a/tests/unit/framework/caching/DbCacheTest.php
+++ b/tests/unit/framework/caching/DbCacheTest.php
@@ -3,12 +3,11 @@
 namespace yiiunit\framework\caching;
 
 use yii\caching\DbCache;
-use yiiunit\TestCase;
 
 /**
  * Class for testing file cache backend
  */
-class DbCacheTest extends CacheTest
+class DbCacheTest extends CacheTestCase
 {
 	private $_cacheInstance;
 	private $_connection;
diff --git a/tests/unit/framework/caching/FileCacheTest.php b/tests/unit/framework/caching/FileCacheTest.php
index b3ac8b7..62f8637 100644
--- a/tests/unit/framework/caching/FileCacheTest.php
+++ b/tests/unit/framework/caching/FileCacheTest.php
@@ -1,12 +1,11 @@
 <?php
 namespace yiiunit\framework\caching;
 use yii\caching\FileCache;
-use yiiunit\TestCase;
 
 /**
  * Class for testing file cache backend
  */
-class FileCacheTest extends CacheTest
+class FileCacheTest extends CacheTestCase
 {
 	private $_cacheInstance = null;
 
diff --git a/tests/unit/framework/caching/MemCacheTest.php b/tests/unit/framework/caching/MemCacheTest.php
index 2855e2c..d110d26 100644
--- a/tests/unit/framework/caching/MemCacheTest.php
+++ b/tests/unit/framework/caching/MemCacheTest.php
@@ -1,12 +1,11 @@
 <?php
 namespace yiiunit\framework\caching;
 use yii\caching\MemCache;
-use yiiunit\TestCase;
 
 /**
  * Class for testing memcache cache backend
  */
-class MemCacheTest extends CacheTest
+class MemCacheTest extends CacheTestCase
 {
 	private $_cacheInstance = null;
 
diff --git a/tests/unit/framework/caching/MemCachedTest.php b/tests/unit/framework/caching/MemCachedTest.php
index bce23ba..8eb8466 100644
--- a/tests/unit/framework/caching/MemCachedTest.php
+++ b/tests/unit/framework/caching/MemCachedTest.php
@@ -1,12 +1,11 @@
 <?php
 namespace yiiunit\framework\caching;
 use yii\caching\MemCache;
-use yiiunit\TestCase;
 
 /**
  * Class for testing memcached cache backend
  */
-class MemCachedTest extends CacheTest
+class MemCachedTest extends CacheTestCase
 {
 	private $_cacheInstance = null;
 
diff --git a/tests/unit/framework/caching/WinCacheTest.php b/tests/unit/framework/caching/WinCacheTest.php
index 1b3399c..373145d 100644
--- a/tests/unit/framework/caching/WinCacheTest.php
+++ b/tests/unit/framework/caching/WinCacheTest.php
@@ -1,12 +1,11 @@
 <?php
 namespace yiiunit\framework\caching;
-use yii\caching\FileCache;
-use yiiunit\TestCase;
+use yii\caching\WinCache;
 
 /**
  * Class for testing wincache backend
  */
-class WinCacheTest extends CacheTest
+class WinCacheTest extends CacheTestCase
 {
 	private $_cacheInstance = null;
 
diff --git a/tests/unit/framework/caching/XCacheTest.php b/tests/unit/framework/caching/XCacheTest.php
index 5e952af..2749295 100644
--- a/tests/unit/framework/caching/XCacheTest.php
+++ b/tests/unit/framework/caching/XCacheTest.php
@@ -1,12 +1,11 @@
 <?php
 namespace yiiunit\framework\caching;
 use yii\caching\XCache;
-use yiiunit\TestCase;
 
 /**
  * Class for testing xcache backend
  */
-class XCacheTest extends CacheTest
+class XCacheTest extends CacheTestCase
 {
 	private $_cacheInstance = null;
 
diff --git a/tests/unit/framework/caching/ZendDataCacheTest.php b/tests/unit/framework/caching/ZendDataCacheTest.php
index 20aa3fc..f630e05 100644
--- a/tests/unit/framework/caching/ZendDataCacheTest.php
+++ b/tests/unit/framework/caching/ZendDataCacheTest.php
@@ -1,12 +1,12 @@
 <?php
 namespace yiiunit\framework\caching;
+use yii\caching\Cache;
 use yii\caching\ZendDataCache;
-use yiiunit\TestCase;
 
 /**
  * Class for testing Zend cache backend
  */
-class ZendDataCacheTest extends CacheTest
+class ZendDataCacheTest extends CacheTestCase
 {
 	private $_cacheInstance = null;
 
diff --git a/tests/unit/framework/db/ActiveRecordTest.php b/tests/unit/framework/db/ActiveRecordTest.php
index f86ca8e..c510cb0 100644
--- a/tests/unit/framework/db/ActiveRecordTest.php
+++ b/tests/unit/framework/db/ActiveRecordTest.php
@@ -1,5 +1,4 @@
 <?php
-
 namespace yiiunit\framework\db;
 
 use yii\db\Query;
@@ -10,7 +9,7 @@ use yiiunit\data\ar\OrderItem;
 use yiiunit\data\ar\Order;
 use yiiunit\data\ar\Item;
 
-class ActiveRecordTest extends \yiiunit\DatabaseTestCase
+class ActiveRecordTest extends DatabaseTestCase
 {
 	protected function setUp()
 	{
diff --git a/tests/unit/framework/db/CommandTest.php b/tests/unit/framework/db/CommandTest.php
index 498df2a..946c31f 100644
--- a/tests/unit/framework/db/CommandTest.php
+++ b/tests/unit/framework/db/CommandTest.php
@@ -7,7 +7,7 @@ use yii\db\Command;
 use yii\db\Query;
 use yii\db\DataReader;
 
-class CommandTest extends \yiiunit\DatabaseTestCase
+class CommandTest extends DatabaseTestCase
 {
 	function testConstruct()
 	{
diff --git a/tests/unit/framework/db/ConnectionTest.php b/tests/unit/framework/db/ConnectionTest.php
index c837b95..d5aa26a 100644
--- a/tests/unit/framework/db/ConnectionTest.php
+++ b/tests/unit/framework/db/ConnectionTest.php
@@ -4,7 +4,7 @@ namespace yiiunit\framework\db;
 
 use yii\db\Connection;
 
-class ConnectionTest extends \yiiunit\DatabaseTestCase
+class ConnectionTest extends DatabaseTestCase
 {
 	function testConstruct()
 	{
diff --git a/tests/unit/DatabaseTestCase.php b/tests/unit/framework/db/DatabaseTestCase.php
similarity index 91%
rename from tests/unit/DatabaseTestCase.php
rename to tests/unit/framework/db/DatabaseTestCase.php
index 9d54173..429d961 100644
--- a/tests/unit/DatabaseTestCase.php
+++ b/tests/unit/framework/db/DatabaseTestCase.php
@@ -1,8 +1,9 @@
 <?php
+namespace yiiunit\framework\db;
 
-namespace yiiunit;
+use yiiunit\TestCase as TestCase;
 
-class DatabaseTestCase extends TestCase
+abstract class DatabaseTestCase extends TestCase
 {
 	protected $database;
 	protected $driverName = 'mysql';
diff --git a/tests/unit/framework/db/QueryTest.php b/tests/unit/framework/db/QueryTest.php
index 9486acb..8362906 100644
--- a/tests/unit/framework/db/QueryTest.php
+++ b/tests/unit/framework/db/QueryTest.php
@@ -7,7 +7,7 @@ use yii\db\Command;
 use yii\db\Query;
 use yii\db\DataReader;
 
-class QueryTest extends \yiiunit\DatabaseTestCase
+class QueryTest extends DatabaseTestCase
 {
 	function testSelect()
 	{
diff --git a/tests/unit/framework/db/mssql/MssqlActiveRecordTest.php b/tests/unit/framework/db/mssql/MssqlActiveRecordTest.php
index 2cf0b01..76c30b9 100644
--- a/tests/unit/framework/db/mssql/MssqlActiveRecordTest.php
+++ b/tests/unit/framework/db/mssql/MssqlActiveRecordTest.php
@@ -2,7 +2,9 @@
 
 namespace yiiunit\framework\db\mssql;
 
-class MssqlActiveRecordTest extends \yiiunit\framework\db\ActiveRecordTest
+use yiiunit\framework\db\ActiveRecordTest;
+
+class MssqlActiveRecordTest extends ActiveRecordTest
 {
     protected function setUp()
     {
diff --git a/tests/unit/framework/db/mssql/MssqlCommandTest.php b/tests/unit/framework/db/mssql/MssqlCommandTest.php
index 11d7565..f3c66c1 100644
--- a/tests/unit/framework/db/mssql/MssqlCommandTest.php
+++ b/tests/unit/framework/db/mssql/MssqlCommandTest.php
@@ -2,7 +2,9 @@
 
 namespace yiiunit\framework\db\mssql;
 
-class MssqlCommandTest extends \yiiunit\framework\db\CommandTest
+use yiiunit\framework\db\CommandTest;
+
+class MssqlCommandTest extends CommandTest
 {
     public function setUp()
     {
diff --git a/tests/unit/framework/db/mssql/MssqlConnectionTest.php b/tests/unit/framework/db/mssql/MssqlConnectionTest.php
index 870af0a..42ac380 100644
--- a/tests/unit/framework/db/mssql/MssqlConnectionTest.php
+++ b/tests/unit/framework/db/mssql/MssqlConnectionTest.php
@@ -2,7 +2,9 @@
 
 namespace yiiunit\framework\db\mssql;
 
-class MssqlConnectionTest extends \yiiunit\framework\db\ConnectionTest
+use yiiunit\framework\db\ConnectionTest;
+
+class MssqlConnectionTest extends ConnectionTest
 {
     public function setUp()
     {
diff --git a/tests/unit/framework/db/mssql/MssqlQueryTest.php b/tests/unit/framework/db/mssql/MssqlQueryTest.php
index 17d6681..08af19d 100644
--- a/tests/unit/framework/db/mssql/MssqlQueryTest.php
+++ b/tests/unit/framework/db/mssql/MssqlQueryTest.php
@@ -2,7 +2,9 @@
 
 namespace yiiunit\framework\db\mssql;
 
-class MssqlQueryTest extends \yiiunit\framework\db\QueryTest
+use yiiunit\framework\db\QueryTest;
+
+class MssqlQueryTest extends QueryTest
 {
     public function setUp()
     {
diff --git a/tests/unit/framework/db/sqlite/SqliteActiveRecordTest.php b/tests/unit/framework/db/sqlite/SqliteActiveRecordTest.php
index 4779f85..573108e 100644
--- a/tests/unit/framework/db/sqlite/SqliteActiveRecordTest.php
+++ b/tests/unit/framework/db/sqlite/SqliteActiveRecordTest.php
@@ -1,8 +1,9 @@
 <?php
-
 namespace yiiunit\framework\db\sqlite;
 
-class SqliteActiveRecordTest extends \yiiunit\framework\db\ActiveRecordTest
+use yiiunit\framework\db\ActiveRecordTest;
+
+class SqliteActiveRecordTest extends ActiveRecordTest
 {
     protected function setUp()
     {
diff --git a/tests/unit/framework/db/sqlite/SqliteCommandTest.php b/tests/unit/framework/db/sqlite/SqliteCommandTest.php
index 3898aa2..750ea11 100644
--- a/tests/unit/framework/db/sqlite/SqliteCommandTest.php
+++ b/tests/unit/framework/db/sqlite/SqliteCommandTest.php
@@ -1,8 +1,9 @@
 <?php
-
 namespace yiiunit\framework\db\sqlite;
 
-class SqliteCommandTest extends \yiiunit\framework\db\CommandTest
+use yiiunit\framework\db\CommandTest;
+
+class SqliteCommandTest extends CommandTest
 {
     protected function setUp()
     {
diff --git a/tests/unit/framework/db/sqlite/SqliteConnectionTest.php b/tests/unit/framework/db/sqlite/SqliteConnectionTest.php
index 5685137..e33c5ad 100644
--- a/tests/unit/framework/db/sqlite/SqliteConnectionTest.php
+++ b/tests/unit/framework/db/sqlite/SqliteConnectionTest.php
@@ -1,8 +1,9 @@
 <?php
-
 namespace yiiunit\framework\db\sqlite;
 
-class SqliteConnectionTest extends \yiiunit\framework\db\ConnectionTest
+use yiiunit\framework\db\ConnectionTest;
+
+class SqliteConnectionTest extends ConnectionTest
 {
     protected function setUp()
     {
diff --git a/tests/unit/framework/db/sqlite/SqliteQueryTest.php b/tests/unit/framework/db/sqlite/SqliteQueryTest.php
index 2a3a831..66068d2 100644
--- a/tests/unit/framework/db/sqlite/SqliteQueryTest.php
+++ b/tests/unit/framework/db/sqlite/SqliteQueryTest.php
@@ -1,16 +1,9 @@
 <?php
-/**
- * Created by JetBrains PhpStorm.
- * User: RusMaxim
- * Date: 09.05.13
- * Time: 21:41
- * To change this template use File | Settings | File Templates.
- */
-
 namespace yiiunit\framework\db\sqlite;
 
+use yiiunit\framework\db\QueryTest;
 
-class SqliteQueryTest extends \yiiunit\framework\db\QueryTest
+class SqliteQueryTest extends QueryTest
 {
     protected function setUp()
     {
diff --git a/tests/unit/framework/helpers/ArrayHelperTest.php b/tests/unit/framework/helpers/ArrayHelperTest.php
index 60a129f..84277d6 100644
--- a/tests/unit/framework/helpers/ArrayHelperTest.php
+++ b/tests/unit/framework/helpers/ArrayHelperTest.php
@@ -3,10 +3,10 @@
 namespace yiiunit\framework\helpers;
 
 use yii\helpers\ArrayHelper;
-use yii\helpers\VarDumper;
+use yii\test\TestCase;
 use yii\web\Sort;
 
-class ArrayHelperTest extends \yii\test\TestCase
+class ArrayHelperTest extends TestCase
 {
 	public function testMerge()
 	{
diff --git a/tests/unit/framework/helpers/JsonTest.php b/tests/unit/framework/helpers/JsonTest.php
index 1795ce6..5504985 100644
--- a/tests/unit/framework/helpers/JsonTest.php
+++ b/tests/unit/framework/helpers/JsonTest.php
@@ -4,9 +4,10 @@
 namespace yiiunit\framework\helpers;
 
 use yii\helpers\Json;
+use yii\test\TestCase;
 use yii\web\JsExpression;
 
-class JsonTest extends \yii\test\TestCase
+class JsonTest extends TestCase
 {
 	public function testEncode()
 	{
diff --git a/tests/unit/framework/helpers/StringHelperTest.php b/tests/unit/framework/helpers/StringHelperTest.php
index ac6ff34..b7f422a 100644
--- a/tests/unit/framework/helpers/StringHelperTest.php
+++ b/tests/unit/framework/helpers/StringHelperTest.php
@@ -1,11 +1,12 @@
 <?php
 namespace yiiunit\framework\helpers;
 use \yii\helpers\StringHelper as StringHelper;
+use yii\test\TestCase;
 
 /**
  * StringHelperTest
  */
-class StringHelperTest extends \yii\test\TestCase
+class StringHelperTest extends TestCase
 {
 	public function testStrlen()
 	{
diff --git a/tests/unit/framework/helpers/VarDumperTest.php b/tests/unit/framework/helpers/VarDumperTest.php
index e734863..7cd04a5 100644
--- a/tests/unit/framework/helpers/VarDumperTest.php
+++ b/tests/unit/framework/helpers/VarDumperTest.php
@@ -1,8 +1,9 @@
 <?php
 namespace yiiunit\framework\helpers;
 use \yii\helpers\VarDumper;
+use yii\test\TestCase;
 
-class VarDumperTest extends \yii\test\TestCase
+class VarDumperTest extends TestCase
 {
 	public function testDumpObject()
 	{
diff --git a/tests/unit/framework/rbac/ManagerTestBase.php b/tests/unit/framework/rbac/ManagerTestCase.php
similarity index 99%
rename from tests/unit/framework/rbac/ManagerTestBase.php
rename to tests/unit/framework/rbac/ManagerTestCase.php
index 1476f9d..7cb4941 100644
--- a/tests/unit/framework/rbac/ManagerTestBase.php
+++ b/tests/unit/framework/rbac/ManagerTestCase.php
@@ -6,7 +6,7 @@ use yii\rbac\Assignment;
 use yii\rbac\Item;
 use yiiunit\TestCase;
 
-abstract class ManagerTestBase extends TestCase
+abstract class ManagerTestCase extends TestCase
 {
 	/** @var \yii\rbac\PhpManager|\yii\rbac\DbManager */
 	protected $auth;
diff --git a/tests/unit/framework/rbac/PhpManagerTest.php b/tests/unit/framework/rbac/PhpManagerTest.php
index d5ab41b..b3b7c4f 100644
--- a/tests/unit/framework/rbac/PhpManagerTest.php
+++ b/tests/unit/framework/rbac/PhpManagerTest.php
@@ -5,9 +5,7 @@ namespace yiiunit\framework\rbac;
 use Yii;
 use yii\rbac\PhpManager;
 
-//require_once(__DIR__ . '/ManagerTestBase.php');
-
-class PhpManagerTest extends ManagerTestBase
+class PhpManagerTest extends ManagerTestCase
 {
 	protected function setUp()
 	{
diff --git a/tests/unit/framework/web/UrlManagerTest.php b/tests/unit/framework/web/UrlManagerTest.php
index 553b163..0f08790 100644
--- a/tests/unit/framework/web/UrlManagerTest.php
+++ b/tests/unit/framework/web/UrlManagerTest.php
@@ -3,8 +3,9 @@ namespace yiiunit\framework\web;
 
 use yii\web\Request;
 use yii\web\UrlManager;
+use yiiunit\TestCase;
 
-class UrlManagerTest extends \yiiunit\TestCase
+class UrlManagerTest extends TestCase
 {
 	public function testCreateUrl()
 	{
diff --git a/tests/unit/framework/web/UrlRuleTest.php b/tests/unit/framework/web/UrlRuleTest.php
index e0761ba..f697805 100644
--- a/tests/unit/framework/web/UrlRuleTest.php
+++ b/tests/unit/framework/web/UrlRuleTest.php
@@ -5,8 +5,9 @@ namespace yiiunit\framework\web;
 use yii\web\UrlManager;
 use yii\web\UrlRule;
 use yii\web\Request;
+use yiiunit\TestCase;
 
-class UrlRuleTest extends \yiiunit\TestCase
+class UrlRuleTest extends TestCase
 {
 	public function testCreateUrl()
 	{