Add cucumber-scalatest example project

Co-authored-by: gaeljw <18280708+gaeljw@users.noreply.github.com>

Author: Copilot

build.sbt

@@ -94,7 +94,8 @@ lazy val root = (project in file("."))
       integrationTestsPicoContainer.projectRefs ++
       integrationTestsScalatest.projectRefs ++
       examplesJunit4.projectRefs ++
-      examplesJunit5.projectRefs: _*
+      examplesJunit5.projectRefs ++
+      examplesScalatest.projectRefs: _*
   )
 
 // Main project
@@ -275,6 +276,20 @@ lazy val examplesJunit5 = (projectMatrix in file("examples/examples-junit5"))
   .dependsOn(cucumberScala % Test)
   .jvmPlatform(scalaVersions = Seq(scala3, scala213))
 
+lazy val examplesScalatest = (projectMatrix in file("examples/examples-scalatest"))
+  .settings(commonSettings)
+  .settings(scalatestSbtSupport)
+  .settings(
+    name := "scala-examples-scalatest",
+    libraryDependencies ++= Seq(
+      "org.scalatest" %% "scalatest" % scalatestVersion % Test
+    ),
+    publishArtifact := false
+  )
+  .dependsOn(cucumberScala % Test)
+  .dependsOn(cucumberScalatest % Test)
+  .jvmPlatform(scalaVersions = Seq(scala3, scala213))
+
 // Version policy check
 
 ThisBuild / versionScheme := Some("early-semver")

examples/examples-scalatest/src/main/scala/cucumber/examples/scalacalculator/RpnCalculator.scala

@@ -0,0 +1,34 @@
+package cucumber.examples.scalacalculator
+
+import scala.collection.mutable.Queue
+
+sealed trait Arg
+
+object Arg {
+  implicit def op(s: String): Op = Op(s)
+  implicit def value(v: Double): Val = Val(v)
+}
+
+case class Op(value: String) extends Arg
+case class Val(value: Double) extends Arg
+
+class RpnCalculator {
+  private val stack = Queue.empty[Double]
+
+  private def op(f: (Double, Double) => Double) =
+    stack += f(stack.dequeue(), stack.dequeue())
+
+  def push(arg: Arg): Unit = {
+    arg match {
+      case Op("+")    => op(_ + _)
+      case Op("-")    => op(_ - _)
+      case Op("*")    => op(_ * _)
+      case Op("/")    => op(_ / _)
+      case Val(value) => stack += value
+      case _          => ()
+    }
+    ()
+  }
+
+  def value: Double = stack.head
+}

examples/examples-scalatest/src/test/resources/cucumber/examples/scalacalculator/basic_arithmetic.feature

@@ -0,0 +1,7 @@
+@foo
+Feature: Basic Arithmetic
+
+  Scenario: Adding
+  # Try to change one of the values below to provoke a failure
+    When I add 4.0 and 5.0
+    Then the result is 9.0

examples/examples-scalatest/src/test/resources/junit-platform.properties

@@ -0,0 +1,4 @@
+cucumber.plugin=pretty
+# Workaround for https://github.com/sbt/sbt-jupiter-interface/issues/142
+# See also https://github.com/cucumber/cucumber-jvm/pull/3023
+cucumber.junit-platform.discovery.as-root-engine=false

examples/examples-scalatest/src/test/scala/cucumber/examples/scalacalculator/RpnCalculatorStepDefinitions.scala

@@ -0,0 +1,22 @@
+package cucumber.examples.scalacalculator
+
+import io.cucumber.scala.{EN, ScalaDsl, Scenario}
+
+class RpnCalculatorStepDefinitions extends ScalaDsl with EN {
+
+  val calc = new RpnCalculator
+
+  When("""I add {double} and {double}""") { (arg1: Double, arg2: Double) =>
+    calc push arg1
+    calc push arg2
+    calc push "+"
+  }
+
+  Then("the result is {double}") { (expected: Double) =>
+    assert(math.abs(expected - calc.value) < 0.001, s"Expected $expected but got ${calc.value}")
+  }
+
+  Before("not @foo") { (scenario: Scenario) =>
+    println(s"Runs before scenarios *not* tagged with @foo (${scenario.getId})")
+  }
+}

examples/examples-scalatest/src/test/scala/cucumber/examples/scalacalculator/RunCukesTest.scala

@@ -0,0 +1,10 @@
+package cucumber.examples.scalacalculator
+
+import io.cucumber.scalatest.{CucumberOptions, CucumberSuite}
+
+@CucumberOptions(
+  features = Array("classpath:cucumber/examples/scalacalculator"),
+  glue = Array("cucumber.examples.scalacalculator"),
+  plugin = Array("pretty")
+)
+class RunCukesTest extends CucumberSuite