feat: Add scala-cli script generator to verify jdk classes

.github/workflows/verify-jdk9-classes.yml

@@ -0,0 +1,58 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+name: Verify JDK9 classes
+
+on:
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  verify-jdk9-classes-check:
+    name: Verify JDK9 classes
+    runs-on: ubuntu-20.04
+    if: github.repository == 'apache/incubator-pekko'
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+          fetch-tags: true
+
+      - name: Setup Java 11
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: 11
+
+      - name: Cache Coursier cache
+        uses: coursier/cache-action@v6
+
+      - name: Publish Stream module local
+        run: sbt ";stream / publishLocal ;"
+
+      - uses: VirtusLab/[email protected]
+      - name: Use Scala-CLI to check
+        run: |-
+          scala-cli --version
+          scala-cli stream/target/scala-cli/VerifyJDK9Classes.sc || (
+          echo "Error when VerifyJDK9Classes"
+          exit 1
+          )
+

build.sbt

@@ -434,6 +434,7 @@ lazy val stream = pekkoModule("stream")
   .settings(AutomaticModuleName.settings("pekko.stream"))
   .settings(OSGi.stream)
   .settings(Protobuf.settings)
+  .settings(VerifyJDK9Classes.settings)
   .enablePlugins(BoilerplatePlugin, Jdk9)
 
 lazy val streamTestkit = pekkoModule("stream-testkit")

project/VerifyJDK9Classes.scala

@@ -0,0 +1,84 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+object VerifyJDK9Classes {
+  import sbt.*
+  import sbt.Keys.*
+
+  lazy val settings: Seq[Setting[_]] = inConfig(Compile) {
+    Seq {
+      sourceGenerators += {
+        generateAndWriteScalaCLIScript(
+          target,
+          _ / "scala-cli" / "VerifyJDK9Classes.sc")
+      }
+    }
+  }
+
+  def generateAndWriteScalaCLIScript(dir: SettingKey[File], locate: File => File): Def.Initialize[Task[Seq[sbt.File]]] =
+    Def.task[Seq[File]] {
+      val script = generateScalaCLIScript(version.value)
+      val file = locate(dir.value)
+      val content = script.stripMargin.format(version.value)
+      if (!file.exists || IO.read(file) != content) IO.write(file, content)
+      // the generated file is not used.
+      Nil
+    }
+
+  private def generateScalaCLIScript(version: String): String =
+    s"""
+      |/*
+      | * Licensed to the Apache Software Foundation (ASF) under one or more
+      | * contributor license agreements. See the NOTICE file distributed with
+      | * this work for additional information regarding copyright ownership.
+      | * The ASF licenses this file to You under the Apache License, Version 2.0
+      | * (the "License"); you may not use this file except in compliance with
+      | * the License. You may obtain a copy of the License at
+      | *
+      | *    http://www.apache.org/licenses/LICENSE-2.0
+      | *
+      | * Unless required by applicable law or agreed to in writing, software
+      | * distributed under the License is distributed on an "AS IS" BASIS,
+      | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+      | * See the License for the specific language governing permissions and
+      | * limitations under the License.
+      | */
+      |//> using dep "org.apache.pekko::pekko-stream:${version}"
+      |////> using jvm 11
+      |object VerifyJDK9Classes {
+      |  def main(args: Array[String]): Unit = {
+      |    import org.apache.pekko.actor.ActorSystem
+      |    import org.apache.pekko.stream.scaladsl.{ JavaFlowSupport, Source }
+      |
+      |    import java.lang.System.exit
+      |    import scala.concurrent.Await
+      |    import scala.concurrent.duration.DurationInt
+      |    implicit val system: ActorSystem = ActorSystem.create("test")
+      |    val future = Source(1 to 3).runWith(
+      |      JavaFlowSupport.Sink.asPublisher[Int](fanout = false).mapMaterializedValue { p =>
+      |        JavaFlowSupport.Source.fromPublisher(p).runFold(0)(_ + _)
+      |      })
+      |
+      |    val result = Await.result(future, 3.seconds)
+      |    println(s"Result:" + result)
+      |    system.terminate()
+      |    exit(if (result == 6) 0 else 1)
+      |  }
+      |}
+      |
+      |""".stripMargin
+}