improvement: convert workspace folder to be a Metals project on chose…

…n commands (e.g. import build)

also assume, that workspace folder is Metals project if it contains `.bloop` folder

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

@@ -393,7 +393,9 @@ object MetalsEnrichments
     def isScalaProject(): Boolean =
       containsProjectFilesSatisfying(_.isScala)
     def isMetalsProject(): Boolean =
-      containsProjectFilesSatisfying(_.isScalaOrJavaFilename)
+      path.resolve(".metals").exists ||
+        path.resolve(".bloop").exists ||
+        containsProjectFilesSatisfying(_.isScalaOrJavaFilename)
 
     private def containsProjectFilesSatisfying(
         fileNamePredicate: String => Boolean

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

@@ -102,7 +102,7 @@ class WorkspaceFolders(
     } yield ()
   }
 
-  def convertToScalaProject(folder: Folder): Option[MetalsLspService] = {
+  def convertToScalaProject(folder: Folder): Option[ProjectMetalsLspService] = {
     val WorkspaceFoldersServices(after, _) =
       folderServices.updateAndGet {
         case wfs @ WorkspaceFoldersServices(

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

@@ -329,17 +329,40 @@ class WorkspaceLspService(
   def onCurrentFolder[A](
       f: ProjectMetalsLspService => Future[A],
       actionName: String,
+      forceMetalsProject: Boolean,
       default: () => A,
   ): Future[A] = {
+    def forcedFocusedToBeMetalsProject(): Option[ProjectMetalsLspService] =
+      nonScalaProjects match {
+        case Nil => None
+        case head :: Nil if folderServices.isEmpty =>
+          workspaceFolders.convertToScalaProject(head)
+        case _ =>
+          focusedDocument
+            .get()
+            .flatMap(getFolderForOpt(_, nonScalaProjects))
+            .flatMap(workspaceFolders.convertToScalaProject)
+      }
     def currentService(): Future[Option[ProjectMetalsLspService]] =
       folderServices match {
+        case Nil if forceMetalsProject =>
+          Future { forcedFocusedToBeMetalsProject() }
         case Nil => Future { None }
-        case head :: Nil => Future { Some(head) }
-        case _ =>
+        case head :: rest =>
           focusedDocument.get().flatMap(getServiceForOpt) match {
             case Some(service) => Future { Some(service) }
             case None =>
-              workspaceChoicePopup.interactiveChooseFolder(actionName)
+              if (rest.isEmpty) {
+                Future { Some(head) }
+              } else if (forceMetalsProject) {
+                forcedFocusedToBeMetalsProject()
+                  .map(folder => Future.successful(Some(folder)))
+                  .getOrElse(
+                    workspaceChoicePopup.interactiveChooseFolder(actionName)
+                  )
+              } else {
+                workspaceChoicePopup.interactiveChooseFolder(actionName)
+              }
           }
       }
     currentService().flatMap {
@@ -357,8 +380,9 @@ class WorkspaceLspService(
   def onCurrentFolder(
       f: ProjectMetalsLspService => Future[Unit],
       actionName: String,
+      forceMetalsProject: Boolean = false,
   ): Future[Unit] =
-    onCurrentFolder(f, actionName, () => ())
+    onCurrentFolder(f, actionName, forceMetalsProject, () => ())
 
   def foreachSeq[A](
       f: ProjectMetalsLspService => Future[A],
@@ -773,18 +797,21 @@ class WorkspaceLspService(
         onCurrentFolder(
           _.generateBspConfig(),
           ServerCommands.GenerateBspConfig.title,
+          forceMetalsProject = true,
         ).asJavaObject
       case ServerCommands.ImportBuild() =>
         onCurrentFolder(
           _.connectionProvider.slowConnectToBuildServer(forceImport = true),
           ServerCommands.ImportBuild.title,
           default = () => BuildChange.None,
+          forceMetalsProject = true,
         ).asJavaObject
       case ServerCommands.ConnectBuildServer() =>
         onCurrentFolder(
           _.connectionProvider.quickConnectToBuildServer(),
           ServerCommands.ConnectBuildServer.title,
           default = () => BuildChange.None,
+          forceMetalsProject = true,
         ).asJavaObject
       case ServerCommands.DisconnectBuildServer() =>
         onCurrentFolder(
@@ -1379,8 +1406,7 @@ class Folder(
 ) {
 
   lazy val isMetalsProject: Boolean =
-    isKnownMetalsProject || path.resolve(".metals").exists || path
-      .isMetalsProject()
+    isKnownMetalsProject || path.isMetalsProject()
 
   /**
    * A workspace folder might be a project reference for an other project.

tests/slow/src/test/scala/tests/gradle/GradleLspSuite.scala

@@ -67,6 +67,38 @@ class GradleLspSuite extends BaseImportSuite("gradle-import") {
     }
   }
 
+  test("i7031") {
+    cleanWorkspace()
+    for {
+      _ <- initialize(
+        Map(
+          "root" -> s"""|/build.gradle
+                        |plugins {
+                        |    id 'scala'
+                        |}
+                        |repositories {
+                        |    mavenCentral()
+                        |}
+                        |dependencies {
+                        |    implementation 'org.scala-lang:scala-library:${V.scala213}'
+                        |}
+                        |""".stripMargin
+        ),
+        expectError = false,
+      )
+      _ <- server.fullServer
+        .executeCommand(ServerCommands.ImportBuild.toExecuteCommandParams())
+        .asScala
+    } yield {
+      assert(server.fullServer.folderServices.nonEmpty)
+      assert(
+        server.headServer.tables.buildTool
+          .selectedBuildTool()
+          .exists(_ == GradleBuildTool.name)
+      )
+    }
+  }
+
   test("inner") {
     client.importBuild = ImportBuild.yes
     cleanWorkspace()