--- title: 9. Commenter Test --- In this test we will check if the commenter, implemented in the [Commenter](/tutorials/custom_language_support/commenter.md) section of the [Custom Language Support Tutorial](/tutorials/custom_language_support_tutorial.md), works as we expect. ### 9.1. Define a test method ```java public void testCommenter() { myFixture.configureByText(SimpleFileType.INSTANCE, "website = http://en.wikipedia.org/"); CommentByLineCommentAction commentAction = new CommentByLineCommentAction(); commentAction.actionPerformedImpl(getProject(), myFixture.getEditor()); myFixture.checkResult("#website = http://en.wikipedia.org/"); commentAction.actionPerformedImpl(getProject(), myFixture.getEditor()); myFixture.checkResult("website = http://en.wikipedia.org/"); } ``` ### 9.2. Run the test Run the test and make sure it's green.