** at 4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:42)** ** at 4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:117)** ** at .runChildren(ParentRunner.java:288)** ** at $1.schedule(ParentRunner.java:71)** ** at nChild(BlockJUnit4ClassRunner.java:57)** ** at nChild(BlockJUnit4ClassRunner.java:78)** ** at .FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)** ** at .FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)**

** at (DelegatingMethodAccessorImpl.java:43)**

** at (NativeMethodAccessorImpl.java:62)** ** at i_introduction._0_Hello_0(HelloWorld.kt:6)** ** Let’s start! Make the function ‘task0’ return “OK”.** ** Using ‘references =’ you can navigate to the code mentioned in the task description.** ** The shortcut in use will be written next to the action name.** ** by choosing “Help → Find Action…” (in the top menu), and typing the action name (“Quick Documentation”).** ** You can see the shortcut for the “Quick Documentation” action used in your IntelliJ IDEA** ** “See also” section gives you a link.** ** Press ‘Ctrl+Q’(Windows) or ‘F1’(Mac OS) on ‘doc0()’ to call the “Quick Documentation” action ** ** Using ‘documentation =’ below the task description you can open the related part of the online documentation.** ** with the correct code according to the problem.** ** Typically you’ll have to replace the function invocation ‘todoTaskN()’, which throws an exception,** ** Kotlin Koans project consists of 42 small tasks for you to solve.**

When I change the code into kotlin-koans/src/i_introduction/_0_Hello_World/HelloWorld.kt by implementing the required solution and I run the test, it seems the binary of the code under test hasn’t changed as I get the following: I’ve enabled Kotlin support under Android Studio 2.3.2. I’ve just started with trying learning Kotlin and I’m going through the Kotlin Koans exercises.

Kotlin koan