Manual Dependancy Injection App testing Play 2.5.x - scala

Question

I have project with manual dependency injection. Can I test my application with standard Play test suite?
play.application.loader="AppLoader"
class AppLoader extends ApplicationLoader {
override def load(context: Context): Application = {
LoggerConfigurator(context.environment.classLoader).foreach(_.configure(context.environment))
new AppComponents(context).application
}
}
}
class AppComponents(context: Context) extends BuiltInComponentsFromContext(context) with EhCacheComponents with EvolutionsComponents with DBComponents with HikariCPComponents{
lazy val applicationController = new controllers.Application(defaultCacheApi, dbApi.database("default"))
lazy val usersController = new controllers.Users(defaultCacheApi)
lazy val assets = new controllers.Assets(httpErrorHandler)
//applicationEvolutions
// Routes is a generated class
override def router: Router = new Routes(httpErrorHandler, applicationController, usersController, assets)
For now test is very simple
class ApplicationTest extends PlaySpec with OneAppPerTest {
"Application" must {
"send 404 on a bad request" in {
route(FakeRequest(GET, "/boum")) mustBe None
}
}
}
Test ends up with error:
Could not find a suitable constructor in controllers.Application. Classes must have either one (and only one) constructor annotated with #Inject or a zero-argument
I presume I need somehow use my AppLoader instead of defualt Guice mechanisam inside ApplicationTest class, because Application controller has dependacy ( cacheApi, dbApi ...)
route method can take application as argument but how can I obtain context to manually instantiate AppLoader class ? Being newbie in Scala recommendations are most welcomed.

Answer 1

This example answered all of my questions:
https://github.com/playframework/play-scala-compile-di-with-tests
Using term compile time dependency injection yield much more results then manual dependency injection.