Plugins can be tested by creating a file called `phpunit.xml` in the base directory with the following content, for example, in a file **/plugins/acme/blog/phpunit.xml**:
Then a **tests/** directory can be created to contain the test classes. The file structure should mimic the base directory with classes having a `Test` suffix. Using a namespace for the class is also recommended.
The test class should extend the base class `PluginTestCase` and this is a special class that will set up the October database stored in memory, as part of the `setUp` method. It will also refresh the plugin being tested, along with any of the defined dependencies in the plugin registration file. This is the equivalent of running the following before each test:
> **Note:** If your plugin uses [configuration files](../plugin/settings#file-configuration), then you will need to run `System\Classes\PluginManager::instance()->registerAll(true);` in the `setUp` method of your tests. Below is an example of a base test case class that should be used if you need to test your plugin working with other plugins instead of in isolation.
use System\Classes\PluginManager;
class BaseTestCase extends PluginTestCase
{
public function setUp()
{
parent::setUp();
// Get the plugin manager
$pluginManager = PluginManager::instance();
// Register the plugins to make features like file configuration available
$pluginManager->registerAll(true);
// Boot all the plugins to test with dependencies of this plugin
$pluginManager->bootAll(true);
}
public function tearDown()
{
parent::tearDown();
// Get the plugin manager
$pluginManager = PluginManager::instance();
// Ensure that plugins are registered again for the next test
$pluginManager->unregisterAll();
}
}
#### Changing database engine for plugins tests
By default OctoberCMS uses SQLite stored in memory for the plugin testing environment. If you want to override the default behavior set the `useConfigForTesting` config to `true` in your `/config/database.php` file. When the `APP_ENV` is `testing` and the `useConfigForTesting` is `true` database parameters will be taken from `/config/database.php`.
You can override the `/config/database.php` file by creating `/config/testing/database.php`. In this case variables from the latter file will be taken.
## System testing
To perform unit testing on the core October files, you should download a development copy using composer or cloning the git repo. This will ensure you have the `tests/` directory.