Default to mainClass in run in Compile not working

[reikje]

I have 2 main classes in my project. Just specifying any of these:

mainClass := Some("project.App")

mainClass in run := Some("project.App")

mainClass in compile := Some("project.App")

will bring up the "Multiple main classes detected, select one to run" dialog in sbt (0.13.0). Using the oneJar scope works. If working as intended, the documentation should be updated.