Test --cross with the test sub-command

Author: Gedochao

modules/integration/src/test/scala/scala/cli/integration/TestTestDefinitions.scala

@@ -12,7 +12,7 @@ abstract class TestTestDefinitions extends ScalaCliSuite with TestScalaVersionAr
     if (actualScalaVersion.startsWith("3.")) Seq("--jvm", "11")
     else Nil
   protected lazy val baseExtraOptions: Seq[String] = TestUtil.extraOptions ++ jvmOptions
-  private lazy val extraOptions: Seq[String]       = scalaVersionArgs ++ baseExtraOptions
+  protected lazy val extraOptions: Seq[String]     = scalaVersionArgs ++ baseExtraOptions
 
   private val utestVersion = "0.8.3"
 

modules/integration/src/test/scala/scala/cli/integration/TestTestsDefault.scala

@@ -4,6 +4,8 @@ import com.eed3si9n.expecty.Expecty.expect
 
 import java.io.File
 
+import scala.cli.integration.Constants.munitVersion
+
 class TestTestsDefault extends TestTestDefinitions with TestDefault {
   test("Pure Java with Scala tests") {
     val inputs = TestInputs(
@@ -40,4 +42,31 @@ class TestTestsDefault extends TestTestDefinitions with TestDefault {
         .call(cwd = root, stdout = os.Inherit)
     }
   }
+
+  test(
+    s"successful test --cross $actualScalaVersion with ${Constants.scala213} and ${Constants.scala212}"
+  ) {
+    val crossVersions   = Seq(actualScalaVersion, Constants.scala213, Constants.scala212)
+    val expectedMessage = "Hello"
+    TestInputs(
+      os.rel / "Cross.test.scala" ->
+        s"""//> using dep org.scalameta::munit::$munitVersion
+           |class MyTests extends munit.FunSuite {
+           |  test("foo") {
+           |    assert(2 + 2 == 4)
+           |    println("$expectedMessage")
+           |  }
+           |}
+           |""".stripMargin,
+      os.rel / "project.scala" -> s"//> using scala ${crossVersions.mkString(" ")}"
+    ).fromRoot { root =>
+      val output = os.proc(TestUtil.cli, "test", extraOptions, ".", "--cross", "--power")
+        .call(cwd = root).out.text()
+      def countOccurrences(a: String, b: String): Int =
+        if (b.isEmpty) 0 // Avoid infinite splitting
+        else a.sliding(b.length).count(_ == b)
+      expect(output.contains(expectedMessage))
+      expect(countOccurrences(output, expectedMessage) == crossVersions.length)
+    }
+  }
 }