I am experiencing a strange behavior of Intellij IDEA 2016.3. Having a class with method foo and a JUnit test for the method when I get java.lang.Exceptio
In addition to the other answers here: the error can also happen when you forget @Test before your test method declaration. IntelliJ (2018.1) will still show you the green "Play-Button" for test execution, but that public method in your Test-Class will not be an actual test.