[//]: # (title: Testing a Custom Language Plugin) > Please see [Testing Plugins](testing_plugins.md) for a general introduction. > {type="note"} This tutorial demonstrates how to write and run automated tests for a custom language plugin. As an example, the plugin implemented in the [Custom Language Support Tutorial](custom_language_support_tutorial.md) is used to demonstrate functional test development. The plugin and test code can be found in the [simple_language_plugin](https://github.com/JetBrains/intellij-sdk-code-samples/tree/main/simple_language_plugin) code sample. * [](tests_prerequisites.md) * [](parsing_test.md) * [](completion_test.md) * [](annotator_test.md) * [](formatter_test.md) * [](rename_test.md) * [](folding_test.md) * [](find_usages_test.md) * [](commenter_test.md) * [](reference_test.md) * [](documentation_test.md)