Added a new Session/ArrayHandler that can be used during testing.

system/Session/Handlers/ArrayHandler.php

@@ -0,0 +1,152 @@
+<?php
+
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2014-2019 British Columbia Institute of Technology
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @package    CodeIgniter
+ * @author     CodeIgniter Dev Team
+ * @copyright  2014-2019 British Columbia Institute of Technology (https://bcit.ca/)
+ * @license    https://opensource.org/licenses/MIT	MIT License
+ * @link       https://codeigniter.com
+ * @since      Version 4.0.0
+ * @filesource
+ */
+
+namespace CodeIgniter\Session\Handlers;
+
+use CodeIgniter\Session\Exceptions\SessionException;
+use CodeIgniter\Config\BaseConfig;
+use CodeIgniter\Database\BaseConnection;
+use Config\Database;
+
+/**
+ * Session handler using static array for storage.
+ * Intended only for use during testing.
+ */
+class ArrayHandler extends BaseHandler implements \SessionHandlerInterface
+{
+	protected static $cache = [];
+
+	//--------------------------------------------------------------------
+
+	/**
+	 * Open
+	 *
+	 * Ensures we have an initialized database connection.
+	 *
+	 * @param string $savePath Path to session files' directory
+	 * @param string $name     Session cookie name
+	 *
+	 * @return boolean
+	 * @throws \Exception
+	 */
+	public function open($savePath, $name): bool
+	{
+		return true;
+	}
+
+	//--------------------------------------------------------------------
+
+	/**
+	 * Read
+	 *
+	 * Reads session data and acquires a lock
+	 *
+	 * @param string $sessionID Session ID
+	 *
+	 * @return string    Serialized session data
+	 */
+	public function read($sessionID): string
+	{
+		return '';
+	}
+
+	//--------------------------------------------------------------------
+
+	/**
+	 * Write
+	 *
+	 * Writes (create / update) session data
+	 *
+	 * @param string $sessionID   Session ID
+	 * @param string $sessionData Serialized session data
+	 *
+	 * @return boolean
+	 */
+	public function write($sessionID, $sessionData): bool
+	{
+		return true;
+	}
+
+	//--------------------------------------------------------------------
+
+	/**
+	 * Close
+	 *
+	 * Releases locks and closes file descriptor.
+	 *
+	 * @return boolean
+	 */
+	public function close(): bool
+	{
+		return true;
+	}
+
+	//--------------------------------------------------------------------
+
+	/**
+	 * Destroy
+	 *
+	 * Destroys the current session.
+	 *
+	 * @param string $sessionID
+	 *
+	 * @return boolean
+	 */
+	public function destroy($sessionID): bool
+	{
+		return true;
+	}
+
+	//--------------------------------------------------------------------
+
+	/**
+	 * Garbage Collector
+	 *
+	 * Deletes expired sessions
+	 *
+	 * @param integer $maxlifetime Maximum lifetime of sessions
+	 *
+	 * @return boolean
+	 */
+	public function gc($maxlifetime): bool
+	{
+		return true;
+	}
+
+	//--------------------------------------------------------------------
+}

user_guide_src/source/libraries/sessions.rst

@@ -441,6 +441,7 @@ Preference                     Default                                   Options
                                                                          CodeIgniter\Session\Handlers\DatabaseHandler
                                                                          CodeIgniter\Session\Handlers\MemcachedHandler
                                                                          CodeIgniter\Session\Handlers\RedisHandler
+                                                                         CodeIgniter\Session\Handlers\ArrayHandler
 **sessionCookieName**          ci_session                                [A-Za-z\_-] characters only                    The name used for the session cookie.
 **sessionExpiration**          7200 (2 hours)                            Time in seconds (integer)                      The number of seconds you would like the session to last.
                                                                                                                         If you would like a non-expiring session (until browser is closed) set the value to zero: 0
@@ -488,6 +489,7 @@ engines, that you can use:
   - CodeIgniter\Session\Handlers\DatabaseHandler
   - CodeIgniter\Session\Handlers\MemcachedHandler
   - CodeIgniter\Session\Handlers\RedisHandler
+  - CodeIgniter\Session\Handlers\ArrayHandler
 
 By default, the ``FileHandler`` Driver will be used when a session is initialized,
 because it is the safest choice and is expected to work everywhere
@@ -498,6 +500,9 @@ line in your **app/Config/App.php** file, if you chose to do so.
 Have it in mind though, every driver has different caveats, so be sure to
 get yourself familiar with them (below) before you make that choice.
 
+.. note:: The ArrayHandler is used during testing and stores all data within
+    a PHP array, while preventing the data from being persisted.
+
 FileHandler Driver (the default)
 ==================================================================