build.sbt

name := "compiler-benchmark"

version := "1.0-SNAPSHOT"

def scala212 = "2.12.15"
def dottyLatest = "0.25.0"
ThisBuild / scalaVersion := scala212
val JmhConfig = config("jmh")

commands += Command.command("testAll") { s =>
  "Test/compile" ::
    "compilation/test" ::
    "hot -psource=scalap -wi 1 -i 1 -f1" ::
    s"++$dottyLatest" ::
    "compilation/test" ::
    "hot -psource=re2s -wi 1 -i 1 -f1" ::
    s"++$scala212" ::
    "micro/Jmh/run -w1 -f1" ::
    s
}

ThisBuild / resolvers += "scala-integration" at "https://scala-ci.typesafe.com/artifactory/scala-integration/"

// Convenient access to builds from PR validation
ThisBuild / resolvers ++= (
  if (scalaVersion.value.endsWith("-SNAPSHOT"))
    List(
      "pr-scala snapshots" at "https://scala-ci.typesafe.com/artifactory/scala-pr-validation-snapshots/",
      )
  else
    Nil
)

ThisBuild / resolvers += Resolver.mavenLocal

lazy val infrastructure = addJmh(project).settings(
  description := "Infrastrucuture to persist benchmark results annotated with metadata from Git",
  autoScalaLibrary := false,
  crossPaths := false,
  libraryDependencies ++= Seq(
    "org.influxdb" % "influxdb-java" % "2.21",
    "org.eclipse.jgit" % "org.eclipse.jgit" % "4.6.0.201612231935-r",
    "com.google.guava" % "guava" % "21.0",
    "org.apache.commons" % "commons-lang3" % "3.5",
    "com.typesafe" % "config" % "1.3.1",
    "org.slf4j" % "slf4j-api" % "1.7.24",
    "org.slf4j" % "log4j-over-slf4j" % "1.7.24",  // for any java classes looking for this
    "ch.qos.logback" % "logback-classic" % "1.2.1"
  )
)

lazy val compilation = addJmh(project).settings(
  // We should be able to switch this project to a broad range of Scala versions for comparative
  // benchmarking. As such, this project should only depend on the high level `MainClass` compiler API.
  description := "Black box benchmark of the compiler",
  libraryDependencies += {
    if (isDotty.value) "ch.epfl.lamp" %% "dotty-compiler" % scalaVersion.value
    else scalaOrganization.value % "scala-compiler" % scalaVersion.value
  },
  crossScalaVersions := List(scala212, dottyLatest),
  Compile / unmanagedSourceDirectories +=
    (Compile / sourceDirectory).value / (if (isDotty.value) "dotc" else "scalac"),
  Jmh / run / mainClass := Some("scala.bench.ScalacBenchmarkRunner"),
  libraryDependencies += "com.novocode" % "junit-interface" % "0.11" % Test,
  Test / testOptions += Tests.Argument(TestFrameworks.JUnit),
  Test / test / fork := true, // jmh scoped tasks run with fork := true.
).settings(addJavaOptions).dependsOn(infrastructure)

lazy val javaCompilation = addJmh(project).settings(
  description := "Black box benchmark of the java compiler",
  crossPaths := false,
  Jmh / run / mainClass := Some("scala.bench.ScalacBenchmarkRunner"),
  libraryDependencies += "com.novocode" % "junit-interface" % "0.11" % Test,
  Test / testOptions += Tests.Argument(TestFrameworks.JUnit),
  Test / test/ fork := true // jmh scoped tasks run with fork := true.
).settings(addJavaOptions).dependsOn(infrastructure)

lazy val micro = addJmh(project).settings(
  description := "Finer grained benchmarks of compiler internals",
  libraryDependencies += scalaOrganization.value % "scala-compiler" % scalaVersion.value
).settings(addJavaOptions).dependsOn(infrastructure)

lazy val jvm = addJmh(project).settings(
  description := "Pure Java benchmarks for demonstrating performance anomalies independent from the Scala language/library",
  autoScalaLibrary := false,
  crossPaths := false
).settings(addJavaOptions).dependsOn(infrastructure)

lazy val addJavaOptions = javaOptions ++= {
  def refOf(version: String) = {
    val HasSha = """.*(?:bin|pre)-([0-9a-f]{7,})(?:-.*)?""".r 
    version match {
      case HasSha(sha) => sha
      case _ => "v" + version
    }
  }
  List(
    "-DscalaVersion=" + scalaVersion.value,
    "-DscalaRef=" + refOf(scalaVersion.value),
    "-Dsbt.launcher=" + (sys.props("java.class.path").split(java.io.File.pathSeparatorChar).find(_.contains("sbt-launch")).getOrElse(""))
  )
}

addCommandAlias("hot", "compilation/jmh:run HotScalacBenchmark -foe true")

addCommandAlias("cold", "compilation/jmh:run ColdScalacBenchmark -foe true")

commands ++= build.Profiler.commands

// duplicated in project/build.sbt
val jmhV = System.getProperty("jmh.version", "1.31")

def addJmh(project: Project): Project = {
  // IntelliJ SBT project import doesn't like sbt-jmh's default setup, which results the prod and test
  // output paths overlapping. This is because sbt-jmh declares the `jmh` config as extending `test`, but
  // configures `classDirectory in Jmh := classDirectory in Compile`.
  project.enablePlugins(JmhPlugin).overrideConfigs(JmhConfig.extend(Compile)).settings(
    Jmh / version := jmhV
  )
}