project/Common.scala

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * license agreements; and to You under the Apache License, version 2.0:
 *
 *   https://www.apache.org/licenses/LICENSE-2.0
 *
 * This file is part of the Apache Pekko project, which was derived from Akka.
 */

/*
 * Copyright (C) 2017-2020 Lightbend Inc. <https://www.lightbend.com>
 */

import sbt._
import Keys._
import com.lightbend.paradox.projectinfo.ParadoxProjectInfoPluginKeys._
import com.typesafe.tools.mima.plugin.MimaKeys._

object Common extends AutoPlugin {
  override def trigger: PluginTrigger = allRequirements
  override lazy val projectSettings = Seq(
    projectInfoVersion := (if (isSnapshot.value) "snapshot" else version.value),
    scalacOptions ++= Seq(
      "-deprecation",
      "-encoding", "UTF-8", // yes, this is 2 args
      "-unchecked",
      "-Ywarn-dead-code",
      // Silence deprecation notices for changes introduced in Scala 2.12
      // Can be removed when we drop support for Scala 2.12:
      "-Wconf:msg=object JavaConverters in package collection is deprecated:s",
      "-Wconf:msg=is deprecated \\(since 2\\.13\\.:s",
      // tolerate deprecations from Akka 2.6.0 until Pekko 1.1.x where we clean up
      "-Wconf:cat=deprecation&msg=since Akka 2\\.6\\.:s",
      // tolerate deprecations from Akka HTTP 10.2.0 until Pekko 1.1.x where we clean up
      "-Wconf:cat=deprecation&msg=since Akka HTTP 10\\.2\\.:s",
      "-Wconf:msg=reached max recursion depth:s",
      "-release:8"),
    scalacOptions ++= onlyOnScala2(Seq(
      "-Xlint",
      // Silence deprecation notices for changes introduced in Scala 2.12
      // Can be removed when we drop support for Scala 2.12:
      "-Wconf:cat=unused-imports&origin=org.apache.pekko.http.ccompat.*:s",
      // Exhaustivity checking is only useful for simple sealed hierarchies and matches without filters.
      // In all other cases, the warning is non-actionable: you get spurious warnings that need to be suppressed
      // verbosely. So, opt out of those in general.
      "-Wconf:cat=other-match-analysis&msg=match may not be exhaustive:s")).value,
    scalacOptions ++= onlyOnScala3(Seq("-Wconf:cat=deprecation:s")).value,
    javacOptions ++=
      Seq("-encoding", "UTF-8") ++ onlyOnJdk8("-source", "1.8") ++ onlyAfterJdk8("--release", "8"),
    // restrict to 'compile' scope because otherwise it is also passed to
    // javadoc and -target is not valid there.
    // https://github.com/sbt/sbt/issues/1785
    Compile / compile / javacOptions ++=
      // From jdk9 onwards this is covered by the '-release' flag above
      onlyOnJdk8("-target", "1.8"),
    mimaReportSignatureProblems := true,
    Global / parallelExecution := sys.props.getOrElse("pekko.http.parallelExecution", "true") != "false")

  val specificationVersion: String = sys.props("java.specification.version")
  def isJdk8: Boolean =
    VersionNumber(specificationVersion).matchesSemVer(SemanticSelector(s"=1.8"))
  def onlyOnJdk8[T](values: T*): Seq[T] = if (isJdk8) values else Seq.empty[T]
  def onlyAfterJdk8[T](values: T*): Seq[T] = if (isJdk8) Seq.empty[T] else values
  def onlyAfterScala212[T](values: Seq[T]): Def.Initialize[Seq[T]] = Def.setting {
    if (scalaMinorVersion.value >= 12) values else Seq.empty[T]
  }
  def onlyOnScala2[T](values: Seq[T]): Def.Initialize[Seq[T]] = Def.setting {
    if (scalaVersion.value.startsWith("3")) Seq.empty[T] else values
  }
  def onlyOnScala3[T](values: Seq[T]): Def.Initialize[Seq[T]] = Def.setting {
    if (scalaVersion.value.startsWith("3")) values else Seq.empty[T]
  }

  def scalaMinorVersion: Def.Initialize[Long] = Def.setting { CrossVersion.partialVersion(scalaVersion.value).get._2 }

}