The following applies to Play 2.4 projects for Scala 2.11.

When setting up a Play2 Scala project, two test case files are created automatically: test/ApplicationSpec.scala and test/IntegrationSpec.scala. The testcases therein are based on specs2. If you prefer to write your test cases using ScalaTest (I certainly do), then you need to proceed as follow:

Change the libraryDependencies in file build.sbt from:

libraryDependencies ++= Seq(
  jdbc,
  cache,
  ws,
  specs2 % Test
)

to:

libraryDependencies ++= Seq(
  jdbc,
  cache,
  ws,
  "org.scalatestplus" %% "play" % "1.4.0-M4" % "test"
)

Next, change file test/ApplicationSpec.scala from:

import org.specs2.mutable._
import org.specs2.runner._
import org.junit.runner._

import play.api.test._
import play.api.test.Helpers._

/**
 * Add your spec here.
 * You can mock out a whole application including requests, plugins etc.
 * For more information, consult the wiki.
 */
@RunWith(classOf[JUnitRunner])
class ApplicationSpec extends Specification {

  "Application" should {

    "send 404 on a bad request" in new WithApplication{
      route(FakeRequest(GET, "/boum")) must beSome.which (status(_) == NOT_FOUND)
    }

    "render the index page" in new WithApplication{
      val home = route(FakeRequest(GET, "/")).get

      status(home) must equalTo(OK)
      contentType(home) must beSome.which(_ == "text/html")
      contentAsString(home) must contain ("Your new application is ready.")
    }
  }
}

to:

import play.api.test._
import play.api.test.Helpers._
import org.scalatestplus.play._

class ApplicationSpec extends PlaySpec with OneAppPerSuite {

  "Application" should {

    "send 404 on a bad request" in {
      val Some(wrongRoute) = route(FakeRequest(GET, "/boum"))

      status(wrongRoute) mustBe NOT_FOUND
    }

    "render the index page" in {
      val Some(home) = route(FakeRequest(GET, "/"))

      status(home) mustBe OK
      contentType(home) mustBe Some("text/html")
      contentAsString(home) must include ("Your new application is ready.")
    }
  }

}

Finally, change file test/IntegrationSpec.scala from:

import org.specs2.mutable._
import org.specs2.runner._
import org.junit.runner._

import play.api.test._
import play.api.test.Helpers._

/**
 * add your integration spec here.
 * An integration test will fire up a whole play application in a real (or headless) browser
 */
@RunWith(classOf[JUnitRunner])
class IntegrationSpec extends Specification {

  "Application" should {

    "work from within a browser" in new WithBrowser {

      browser.goTo("http://localhost:" + port)

      browser.pageSource must contain("Your new application is ready.")
    }
  }
}

to:

import org.scalatestplus.play._

class IntegrationSpec extends PlaySpec with OneBrowserPerSuite with OneServerPerSuite with HtmlUnitFactory {

  "Application" should {

    "work from within a browser" in {

      go to "http://localhost:" + port

      pageSource must include ("Your new application is ready.")
    }
  }
}

You can also see all neccessary changes in one diff at https://github.com/journeymonitor/analyze/compare/4ef3694…763ff0f.

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