feat: add setting to choose preferred build server

metals/src/main/scala/scala/meta/internal/builds/BloopInstall.scala

@@ -7,7 +7,6 @@ import scala.concurrent.ExecutionContext
 import scala.concurrent.Future
 
 import scala.meta.internal.builds.Digest.Status
-import scala.meta.internal.metals.AutoImportBuildKind
 import scala.meta.internal.metals.BuildInfo
 import scala.meta.internal.metals.Confirmation
 import scala.meta.internal.metals.Messages._
@@ -133,9 +132,7 @@ final class BloopInstall(
  scribe.info(s"skipping build import with status '${result.name}'")
  Future.successful(result)
  case _ =>
- if (
- userConfig().automaticImportBuild == AutoImportBuildKind.Initial || userConfig().automaticImportBuild == AutoImportBuildKind.All
- ) {
+ if (userConfig().shouldAutoImportNewProject) {
  runUnconditionally(buildTool, isImportInProcess)
  } else {
  scribe.debug("Awaiting user response...")

metals/src/main/scala/scala/meta/internal/builds/BuildTool.scala

@@ -34,6 +34,12 @@ trait BuildTool {
  */
  def buildServerName = executableName
 
+ def possibleBuildServerNames: List[String] = List(buildServerName)
+
+ def isBspGenerated(workspace: AbsolutePath): Boolean =
+ possibleBuildServerNames
+ .map(name => workspace.resolve(".bsp").resolve(s"$name.json"))
+ .exists(_.isFile)
 }
 
 object BuildTool {

metals/src/main/scala/scala/meta/internal/builds/ScalaCliBuildTool.scala

@@ -61,13 +61,13 @@ class ScalaCliBuildTool(
 
  override val forcesBuildServer = true
 
- def isBspGenerated(workspace: AbsolutePath): Boolean =
- ScalaCliBuildTool.pathsToScalaCliBsp(workspace).exists(_.isFile)
+ override def possibleBuildServerNames = ScalaCli.names.toList
 
 }
 
 object ScalaCliBuildTool {
  def name = "scala-cli"
+
  def pathsToScalaCliBsp(root: AbsolutePath): List[AbsolutePath] =
  ScalaCli.names.toList.map(name =>
  root.resolve(".bsp").resolve(s"$name.json")

metals/src/main/scala/scala/meta/internal/metals/Messages.scala

@@ -189,6 +189,31 @@ object Messages {
  }
  }
 
+ object GenerateBspAndConnect {
+ def yes = new MessageActionItem("Connect")
+
+ def notNow: MessageActionItem = Messages.notNow
+
+ def params(
+ buildToolName: String,
+ buildServerName: String,
+ ): ShowMessageRequestParams = {
+ val params = new ShowMessageRequestParams()
+ params.setMessage(
+ s"New $buildToolName workspace detected, would you like connect to $buildServerName build server?"
+ )
+ params.setType(MessageType.Info)
+ params.setActions(
+ List(
+ yes,
+ notNow,
+ dontShowAgain,
+ ).asJava
+ )
+ params
+ }
+ }
+
  object MainClass {
  val message = "Multiple main classes found. Which would you like to run?"
  }

metals/src/main/scala/scala/meta/internal/metals/MetalsLspService.scala

@@ -2091,23 +2091,17 @@ class MetalsLspService(
  buildTool: Option[BuildTool.Found],
  chosenBuildServer: Option[String],
  ): Future[BuildChange] = {
- val isBloopOrEmpty = chosenBuildServer.isEmpty || chosenBuildServer.exists(
+ def isBloopOrEmpty = chosenBuildServer.exists(
  _ == BloopServers.name
- )
+ ) || chosenBuildServer.isEmpty
+
+ def useBuildToolBsp(buildTool: BuildServerProvider) =
+ buildTool match {
+ case _: BloopInstallProvider => userConfig.defaultBSPToBuildTool
+ case _ => true
+ }
+
  buildTool match {
- case Some(BuildTool.Found(buildTool: BloopInstallProvider, digest))
- if isBloopOrEmpty =>
- slowConnectToBloopServer(forceImport, buildTool, digest)
- case Some(BuildTool.Found(buildTool: ScalaCliBuildTool, _))
- if !buildTool.isBspGenerated(folder) =>
- tables.buildServers.chooseServer(buildTool.buildServerName)
- buildTool
- .generateBspConfig(
- folder,
- args => bspConfigGenerator.runUnconditionally(buildTool, args),
- statusBar,
- )
- .flatMap(_ => quickConnectToBuildServer())
  // If there is no .bazelbsp present, we ask user to write bsp config
  // After that, we should fall into the last case and index workspace
  case Some(BuildTool.Found(_: BazelBuildTool, _))
@@ -2122,12 +2116,22 @@ class MetalsLspService(
  forceImport,
  )
  .flatMap(_ => quickConnectToBuildServer())
+ case Some(BuildTool.Found(buildTool: BuildServerProvider, _))
+ if chosenBuildServer.isEmpty && useBuildToolBsp(buildTool) =>
+ slowConnectToBuildToolBsp(buildTool)
+ case Some(BuildTool.Found(buildTool: BloopInstallProvider, digest))
+ if isBloopOrEmpty =>
+ slowConnectToBloopServer(forceImport, buildTool, digest)
  case Some(BuildTool.Found(buildTool, _))
  if !chosenBuildServer.exists(
  _ == buildTool.buildServerName
  ) && buildTool.forcesBuildServer =>
  tables.buildServers.chooseServer(buildTool.buildServerName)
  quickConnectToBuildServer()
+ case Some(BuildTool.Found(buildTool: BuildServerProvider, _))
+ if chosenBuildServer.contains(buildTool.buildServerName) && !buildTool
+ .isBspGenerated(folder) =>
+ generateBspAndConnect(buildTool)
  case Some(found) =>
  indexer.reloadWorkspaceAndIndex(
  forceImport,
@@ -2141,6 +2145,51 @@ class MetalsLspService(
  }
  }
 
+ private def slowConnectToBuildToolBsp(
+ buildTool: BuildServerProvider
+ ) = {
+ val notification = tables.dismissedNotifications.ImportChanges
+ if (buildTool.isBspGenerated(folder)) {
+ tables.buildServers.chooseServer(buildTool.buildServerName)
+ quickConnectToBuildServer()
+ } else if (
+ userConfig.shouldAutoImportNewProject || buildTool.forcesBuildServer
+ ) {
+ generateBspAndConnect(buildTool)
+ } else if (notification.isDismissed) {
+ Future.successful(BuildChange.None)
+ } else {
+ scribe.debug("Awaiting user response...")
+ languageClient
+ .showMessageRequest(
+ Messages.GenerateBspAndConnect
+ .params(buildTool.executableName, buildTool.buildServerName)
+ )
+ .asScala
+ .flatMap { item =>
+ if (item == Messages.dontShowAgain) {
+ notification.dismissForever()
+ Future.successful(BuildChange.None)
+ } else if (item == Messages.GenerateBspAndConnect.yes) {
+ generateBspAndConnect(buildTool)
+ } else Future.successful(BuildChange.None)
+ }
+ }
+ }
+
+ private def generateBspAndConnect(
+ buildTool: BuildServerProvider
+ ): Future[BuildChange] = {
+ tables.buildServers.chooseServer(buildTool.buildServerName)
+ buildTool
+ .generateBspConfig(
+ folder,
+ args => bspConfigGenerator.runUnconditionally(buildTool, args),
+ statusBar,
+ )
+ .flatMap(_ => quickConnectToBuildServer())
+ }
+
  /**
  * If there is no auto-connectable build server and no supported build tool is found
  * we assume it's a scala-cli project.

metals/src/main/scala/scala/meta/internal/metals/UserConfiguration.scala

@@ -56,8 +56,12 @@ case class UserConfiguration(
  verboseCompilation: Boolean = false,
  automaticImportBuild: AutoImportBuildKind = AutoImportBuildKind.Off,
  scalaCliLauncher: Option[String] = None,
+ defaultBSPToBuildTool: Boolean = false,
 ) {
 
+ def shouldAutoImportNewProject: Boolean =
+ automaticImportBuild != AutoImportBuildKind.Off
+
  def currentBloopVersion: String =
  bloopVersion.getOrElse(BuildInfo.bloopVersion)
 
@@ -349,6 +353,15 @@ object UserConfiguration {
  |only automatically import a build when a project is first opened, "all" will automate 
  |build imports after subsequent changes as well.""".stripMargin,
  ),
+ UserConfigurationOption(
+ "default-bsp-to-build-tool",
+ "false",
+ "true",
+ "If used build server should default to build tool.",
+ """|If used build server should default to the one provided by the build tool
+ |instead of the default Bloop.
+ |""".stripMargin,
+ ),
  )
 
  def fromJson(
@@ -570,6 +583,11 @@ object UserConfiguration {
  case _ => AutoImportBuildKind.Off
  }
 
+ val scalaCliLauncher = getStringKey("scala-cli-launcher")
+
+ val defaultBSPToBuildTool =
+ getBooleanKey("default-bsp-to-build-tool").getOrElse(false)
+
  if (errors.isEmpty) {
  Right(
  UserConfiguration(
@@ -602,6 +620,8 @@ object UserConfiguration {
  customProjectRoot,
  verboseCompilation,
  autoImportBuilds,
+ scalaCliLauncher,
+ defaultBSPToBuildTool,
  )
  )
  } else {

tests/slow/src/test/scala/tests/PreferredBuildServer.scala

@@ -0,0 +1,80 @@
+package tests
+
+import scala.meta.internal.metals.Messages
+import scala.meta.internal.metals.UserConfiguration
+import scala.meta.internal.metals.{BuildInfo => V}
+
+class PreferredBuildServer extends BaseLspSuite("preferred-build-server") {
+ override def userConfig: UserConfiguration =
+ super.userConfig.copy(defaultBSPToBuildTool = true)
+
+ test("start-sbt-when-preferred-no-bsp") {
+ cleanWorkspace()
+
+ val importMessage =
+ Messages.GenerateBspAndConnect.params("sbt", "sbt").getMessage()
+
+ client.showMessageRequestHandler = msg => {
+ if (msg.getMessage() == importMessage)
+ Some(Messages.GenerateBspAndConnect.notNow)
+ else None
+ }
+
+ val fileLayout =
+ s"""|/project/build.properties
+ |sbt.version=${V.sbtVersion}
+ |/build.sbt
+ |${SbtBuildLayout.commonSbtSettings}
+ |ThisBuild / scalaVersion := "${V.scala213}"
+ |val a = project.in(file("a"))
+ |/a/src/main/scala/a/A.scala
+ |package a
+ |object A {
+ | val a = 1
+ |}
+ |""".stripMargin
+ FileLayout.fromString(fileLayout, workspace)
+
+ for {
+ _ <- server.initialize()
+ _ <- server.initialized()
+ _ = assertNoDiff(
+ client.workspaceMessageRequests,
+ importMessage,
+ )
+ _ = assert(server.server.bspSession.isEmpty)
+ } yield ()
+ }
+
+ test("start-sbt-when-preferred-with-bsp") {
+ cleanWorkspace()
+
+ val fileLayout =
+ s"""|/project/build.properties
+ |sbt.version=${V.sbtVersion}
+ |/build.sbt
+ |${SbtBuildLayout.commonSbtSettings}
+ |ThisBuild / scalaVersion := "${V.scala213}"
+ |val a = project.in(file("a"))
+ |/a/src/main/scala/a/A.scala
+ |package a
+ |object A {
+ | val a = 1
+ |}
+ |""".stripMargin
+
+ FileLayout.fromString(fileLayout, workspace)
+ SbtServerInitializer.generateBspConfig(workspace, V.sbtVersion)
+
+ for {
+ _ <- server.initialize()
+ _ <- server.initialized()
+ _ <- server.server.buildServerPromise.future
+ _ = assertNoDiff(
+ server.server.tables.buildServers.selectedServer().get,
+ "sbt",
+ )
+ _ = assert(server.server.bspSession.exists(_.main.isSbt))
+ } yield ()
+ }
+}

tests/slow/src/test/scala/tests/scalacli/ScalaCliSuite.scala

@@ -312,6 +312,7 @@ class ScalaCliSuite extends BaseScalaCliSuite(V.scala3) {
  }
 
  test("inner") {
+ cleanWorkspace()
  for {
  _ <- scalaCliInitialize(useBsp = false)(
  s"""|/inner/project.scala

tests/unit/src/main/scala/tests/BuildServerInitializer.scala

@@ -133,7 +133,7 @@ object SbtServerInitializer extends BuildServerInitializer {
  }
  }
 
- private def generateBspConfig(
+ def generateBspConfig(
  workspace: AbsolutePath,
  sbtVersion: String,
  ): Unit = {