IntelliJ IDEA Report Highlighting error when using routes in Controller

Question

I have a Scala Play project. I\'m using Play 2.2.1. I downloaded Scala, Play 2 supported and SBT plugins. Everything is OK, but When I call route on Action in the Controller

Answer 1

This is a common problem, it's because IntelliJ needs to be shown where to look for the compiled Scala templates and routes file. Here's how I fixed it on my IntelliJ 12.1 installation:

• Go to the Module Settings for your project in IntelliJ (select the top-level, hit F4)
• Choose the Modules item in the Project Structure window that appears
• Select the projectname item (as opposed to the projectname-build item)
• Add the compiler's output directory to the Source Folders items;
  • For Scala 2.10 it's target/scala-2.10/classes
  • I personally find the IntelliJ UI for this to be very non-intuitive; you might need to take the target directory and/or one of its subdirectories out of the Excluded Folders first
• After applying that change, IntelliJ should see the results of compiling each routes and .scala.html file as just-another source file, so they won't show as "broken" and auto-complete should work for them.

Answer 2

millhouse's answer helped me find the right answer. Play 2.2 (and perhaps earlier versions, haven't checked) output a scala version of the routes file to project_dir/target/scala-2.10/src_managed/main So for IntelliJ to get the highlighting right you need to make sure that src_managed/main is added as a source folder. The reverse routes for javascript are for some reason included in project_dir/target/scala-2.10/classes_managed so you'll have to add that as well. (In your screenshot it looks like classes_managed is set to excluded so you'll want to un-exclude it by pressing the x button on the right hand side.)

Here's a screen shot of my project structure:

Update:

In Play 2.3 (or perhaps recent versions of IntelliJ) adding the classes_managed no longer fixes the problem. Instead of adding classes_managed to the project's sources add it to it's dependencies. By doing that IntelliJ should be able to pick up the compiled routes.class.