Fixes #3168: Improved the performance of yii\rbac\DbManager::checkAccess() by caching mechanism

tests/unit/framework/rbac/MySQLManagerCacheTest.php

@@ -0,0 +1,24 @@
+<?php
+namespace yiiunit\framework\rbac;
+
+use yii\caching\FileCache;
+use yii\rbac\DbManager;
+
+/**
+ * MySQLManagerCacheTest
+ * @group db
+ * @group rbac
+ */
+class MySQLManagerCacheTest extends MySQLManagerTest
+{
+    /**
+     * @return \yii\rbac\ManagerInterface
+     */
+    protected function createManager()
+    {
+        return new DbManager([
+            'db' => $this->getConnection(),
+            'cache' => new FileCache(['cachePath' => '@yiiunit/runtime/cache']),
+        ]);
+    }
+}