How to set vals to be used in tests? - scala

Question

I've been noticing a lot of repetition to set up each test with Play/specs2. I'm aware that you can create a trait that extends mutable.Before and use that to set up tests but any values created there seem to be out of scope for my tests.
What I would like to be able to do is set val user = User.create("User Name") in a class or trait before each test runs so I can have access to user later on in the test. How can this be achieved?
// SpecificationWithFixtures.scala
package models
import org.specs2.execute.{AsResult, Result}
import org.specs2.mutable._
import play.api.test.Helpers._
import play.api.test._
abstract class SpecificationWithFixtures extends Specification {
abstract class WithFakeDB extends WithApplication(FakeApplication(additionalConfiguration = inMemoryDatabase())) {
override def around[T: AsResult](t: => T): Result = super.around {
t
}
}
}
// UserSpec.scala
package models
import org.junit.runner._
import org.specs2.runner._
#RunWith(classOf[JUnitRunner])
class UserSpec extends SpecificationWithFixtures {
"User.create" should {
"save user in the database" in new WithFakeDB {
val user = User.create("User Name")
// Some test for user
}
}
"User.findAll" should {
"return a list of all users" in new WithFakeDB {
val user = User.create("User Name")
// Another test for user
}
}
}

Answer 1

What you can do is something like:
def withUser[T](test: User => T): T = test(User create "Username")
// or even more configurable
def withUser[T](name: String)(test: User => T): T = test(User create name)
// Then writing expectations you can do
"User Roger" in withUser("Roger") {
roger => // trivial example
roger.name must_== "Roger"
}
// or even
"User" in withUser("John") {
_.name must_== "John"
}
This kind of loan pattern is useful writing specs2.
In previous example it's user per expectation (in), but it can be used for a group of expectations (should, >>), or for all.
"User" should withUser("xyz") {
"exp1" in { ??? }
}