Add BSP support

build.sc

@@ -72,6 +72,7 @@ class Build(val crossScalaVersion: String) extends CrossSbtModule with ScalaCliP
     Deps.guava, // for coursierJvm / scalaJsEnvNodeJs, see above
     Deps.nativeTools,
     Deps.osLib,
+    Deps.pprint,
     Deps.pureconfig,
     Deps.scalaJsLinkerInterface,
     Deps.scalametaTrees,
@@ -152,6 +153,11 @@ trait Cli extends SbtModule with CliLaunchers with ScalaCliPublishModule with Fo
   def localRepoJar = `local-repo`.localRepoJar()
   def graalVmVersion = deps.graalVmVersion
 
+  // lsp4j, pulled by metabrowse, brings a class that conflicts with one
+  // defined in bloop, and sometimes creates issues when running
+  // native-image
+  def stripLsp4jPreconditionsFromBsp4j = true
+
   object test extends Tests
 }
 
@@ -194,8 +200,10 @@ trait CliIntegrationBase extends SbtModule with ScalaCliPublishModule with HasTe
   private def mainArtifactName = T{ artifactName() }
   trait Tests extends super.Tests {
     def ivyDeps = super.ivyDeps() ++ Agg(
+      Deps.bsp4j,
       Deps.osLib,
-      Deps.pprint
+      Deps.pprint,
+      Deps.scalaAsync
     )
     def forkEnv = super.forkEnv() ++ Seq(
       "SCALA_CLI" -> testLauncher().path.toString,
@@ -207,6 +215,21 @@ trait CliIntegrationBase extends SbtModule with ScalaCliPublishModule with HasTe
         PathRef(os.Path(ref.path.toString.replace(File.separator + name + File.separator, File.separator)))
       }
     }
+
+    def constantsFile = T{
+      val dest = T.dest / "Constants.scala"
+      val code =
+        s"""package scala.cli.integration
+           |
+           |/** Build-time constants. Generated by mill. */
+           |object Constants {
+           |  def bspVersion = "${Deps.bsp4j.dep.version}"
+           |}
+           |""".stripMargin
+      os.write(dest, code)
+      PathRef(dest)
+    }
+    def generatedSources = super.generatedSources() ++ Seq(constantsFile())
   }
 }
 

modules/bloop-rifle/src/main/scala/scala/build/bloop/BloopServer.scala

@@ -97,19 +97,14 @@ object BloopServer {
     create(System.currentTimeMillis() + timeout.toMillis)
   }
 
-  def buildServer(
+  def bsp(
     config: BloopRifleConfig,
-    clientName: String,
-    clientVersion: String,
     workspace: Path,
-    classesDir: Path,
-    buildClient: bsp4j.BuildClient,
     threads: BloopThreads,
     logger: BloopRifleLogger,
     period: FiniteDuration = 100.milliseconds,
-    timeout: FiniteDuration = 5.seconds,
-    initTimeout: FiniteDuration = 10.seconds
-  ): BloopServer = {
+    timeout: FiniteDuration = 5.seconds
+  ): (BspConnection, Socket) = {
 
     ensureBloopRunning(config, threads.startServerChecks, logger)
 
@@ -126,6 +121,27 @@ object BloopServer {
 
     logger.debug(s"Connected to Bloop via BSP at ${conn.address}")
 
+    (conn, socket)
+  }
+
+  def buildServer(
+    config: BloopRifleConfig,
+    clientName: String,
+    clientVersion: String,
+    workspace: Path,
+    classesDir: Path,
+    buildClient: bsp4j.BuildClient,
+    threads: BloopThreads,
+    logger: BloopRifleLogger,
+    period: FiniteDuration = 100.milliseconds,
+    timeout: FiniteDuration = 5.seconds,
+    initTimeout: FiniteDuration = 10.seconds
+  ): BloopServer = {
+
+    val (conn, socket) = bsp(config, workspace, threads, logger, period, timeout)
+
+    logger.debug(s"Connected to Bloop via BSP at ${conn.address}")
+
     // FIXME As of now, we don't detect when connection gets closed.
     // For TCP connections, this should be do-able with heartbeat messages
     // (to be added to BSP?).

modules/build/src/main/scala/pprint/better.scala

@@ -0,0 +1,36 @@
+package pprint
+
+object better {
+
+  def log[T](x: sourcecode.Text[T],
+             tag: String = "",
+             width: Int = defaultWidth,
+             height: Int = defaultHeight,
+             indent: Int = defaultIndent,
+             initialOffset: Int = 0)
+            (implicit line: sourcecode.Line,
+             fileName: sourcecode.FileName): T = {
+
+    def joinSeq[T](seq: Seq[T], sep: T): Seq[T] = {
+      seq.flatMap(x => Seq(x, sep)).dropRight(1)
+    }
+
+    val tagStrs =
+      if (tag.isEmpty) Seq()
+      else Seq(fansi.Color.Cyan(tag), fansi.Str(" "))
+
+    val prefix = Seq(
+      fansi.Color.Magenta(fileName.value),
+      fansi.Str(":"),
+      fansi.Color.Green(line.value.toString),
+      fansi.Str(" "),
+      fansi.Color.Cyan(x.source),
+      fansi.Str(": ")
+    ) ++ tagStrs
+    val str = fansi.Str.join(prefix ++ tokenize(x.value, width, height, indent).toSeq:_*)
+
+    System.err.println(str)
+    x.value
+  }
+
+}

modules/build/src/main/scala/scala/build/Artifacts.scala

@@ -2,6 +2,8 @@ package scala.build
 
 import coursier.cache.FileCache
 import coursier.cache.loggers.RefreshLogger
+import coursier.core.Classifier
+import coursier.Fetch
 import coursier.parse.RepositoryParser
 import _root_.dependency._
 import scala.build.internal.Constants
@@ -17,11 +19,26 @@ final case class Artifacts(
   compilerArtifacts: Seq[(String, Path)],
   compilerPlugins: Seq[(AnyDependency, String, Path)],
   dependencies: Seq[AnyDependency],
-  artifacts: Seq[(String, Path)],
-  sourceArtifacts: Seq[(String, Path)],
+  detailedArtifacts: Seq[(coursier.Dependency, coursier.core.Publication, coursier.util.Artifact, Path)],
   extraJars: Seq[Path],
   params: ScalaParameters
 ) {
+  lazy val artifacts: Seq[(String, Path)] =
+    detailedArtifacts
+      .iterator
+      .collect {
+        case (dep, pub, a, f) if pub.classifier != Classifier.sources =>
+          (a.url, f)
+      }
+      .toVector
+  lazy val sourceArtifacts: Seq[(String, Path)] =
+    detailedArtifacts
+      .iterator
+      .collect {
+        case (dep, pub, a, f) if pub.classifier == Classifier.sources =>
+          (a.url, f)
+      }
+      .toVector
   lazy val compilerClassPath: Seq[Path] =
     compilerArtifacts.map(_._2)
   lazy val classPath: Seq[Path] =
@@ -87,11 +104,24 @@ object Artifacts {
       jmhDependencies
 
     val compilerArtifacts = artifacts(compilerDependencies, allExtraRepositories, params, logger)
-    val artifacts0 = artifacts(updatedDependencies, allExtraRepositories, params, logger)
 
+    val fetchRes = fetch(
+      updatedDependencies,
+      allExtraRepositories,
+      params,
+      logger,
+      classifiersOpt = Some(Set("_") ++ (if (fetchSources) Set("sources") else Set.empty))
+    )
+    val artifacts0 = {
+      val a = fetchRes.fullExtraArtifacts.iterator.collect { case (a, Some(f)) => (None, a.url, f.toPath) }.toVector ++
+        fetchRes.fullDetailedArtifacts.iterator.collect { case (dep, pub, a, Some(f)) if pub.classifier != Classifier.sources => (Some(dep.moduleVersion), a.url, f.toPath) }.toVector
+      a.distinct
+    }
     val sourceArtifacts =
-      if (fetchSources) artifacts(updatedDependencies, allExtraRepositories, params, logger, classifiersOpt = Some(Set("sources")))
-      else Nil
+      if (fetchSources) {
+        val a = fetchRes.fullDetailedArtifacts.iterator.collect { case (dep, pub, a, Some(f)) if pub.classifier == Classifier.sources => (a.url, f.toPath) }.toVector
+        a.distinct
+      } else Nil
 
     val extraStubsJars =
       if (addStubs)
@@ -115,8 +145,7 @@ object Artifacts {
       compilerArtifacts,
       compilerPlugins0,
       updatedDependencies,
-      artifacts0,
-      sourceArtifacts,
+      fetchRes.fullDetailedArtifacts.collect { case (d, p, a, Some(f)) => (d, p, a, f.toPath) },
       extraJars ++ extraStubsJars,
       params
     )
@@ -129,6 +158,22 @@ object Artifacts {
     logger: Logger,
     classifiersOpt: Option[Set[String]] = None
   ): Seq[(String, Path)] = {
+    val result = fetch(dependencies, extraRepositories, params, logger, classifiersOpt)
+      .artifacts
+      .iterator
+      .map { case (a, f) => (a.url, f.toPath) }
+      .toList
+    logger.debug((Seq(s"Found ${result.length} artifacts:") ++ result.map("  " + _._2) ++ Seq("")).mkString(System.lineSeparator()))
+    result
+  }
+
+  private[build] def fetch(
+    dependencies: Seq[AnyDependency],
+    extraRepositories: Seq[String],
+    params: ScalaParameters,
+    logger: Logger,
+    classifiersOpt: Option[Set[String]]
+  ): Fetch.Result = {
     logger.debug(s"Fetching $dependencies" + (if (extraRepositories.isEmpty) "" else s", adding $extraRepositories"))
 
     val extraRepositories0 = RepositoryParser.repositories(extraRepositories).either match {
@@ -143,16 +188,13 @@ object Artifacts {
       .withCache(cache)
       .addRepositories(extraRepositories0: _*)
       .addDependencies(dependencies.map(_.toCs(params)): _*)
-    for (classifiers <- classifiersOpt)
-      fetcher = fetcher.addClassifiers(classifiers.toSeq.map(coursier.Classifier(_)): _*)
+    for (classifiers <- classifiersOpt) {
+      if (classifiers("_"))
+        fetcher = fetcher.withMainArtifacts()
+      fetcher = fetcher.addClassifiers(classifiers.toSeq.filter(_ != "_").map(coursier.Classifier(_)): _*)
+    }
 
-    val result = fetcher.runResult()
-      .artifacts
-      .iterator
-      .map { case (a, f) => (a.url, f.toPath) }
-      .toList
-    logger.debug((Seq(s"Found ${result.length} artifacts:") ++ result.map("  " + _._2) ++ Seq("")).mkString(System.lineSeparator()))
-    result
+    fetcher.runResult()
   }
 
 }