How to run main class in test folder?

...And if you have multiple projects in you sbt file then:

sbt "projectName/test:runMain path.to.MainObjectInTest"

or just use:

sbt "projectName/test:run"

If you have only one object with main, this will run it. If you have multiple objects with main, it will ask you to select which one to run.

sbt "test:runMain path.to.MainObjectInTest"