improvement: show bsp as connected after the first message from build server

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

@@ -454,10 +454,14 @@ object BuildServerConnection {
     def setupServer(): Future[LauncherConnection] = {
       connect().map { case conn @ SocketConnection(_, output, input, _, _) =>
         val tracePrinter = Trace.setupTracePrinter("BSP", bspTraceRoot)
-        val requestMonitor =
-          if (addLivenessMonitor) Some(new RequestMonitorImpl) else None
+        val bspStatusOpt =
+          if (addLivenessMonitor)
+            Some(new BspStatus(languageClient, serverName, config.icons))
+          else None
+        val requestMonitorOpt =
+          bspStatusOpt.map(new RequestMonitorImpl(_))
         val wrapper: MessageConsumer => MessageConsumer =
-          requestMonitor.map(_.wrapper).getOrElse(identity)
+          requestMonitorOpt.map(_.wrapper).getOrElse(identity)
         val launcher =
           new Launcher.Builder[MetalsBuildServer]()
             .traceMessages(tracePrinter.orNull)
@@ -484,17 +488,16 @@ object BuildServerConnection {
           }
 
         val optServerLivenessMonitor =
-          requestMonitor.map {
-            new ServerLivenessMonitor(
-              _,
-              () => server.workspaceBuildTargets(),
-              languageClient,
-              config.metalsToIdleTime,
-              config.pingInterval,
-              serverName,
-              config.icons,
-            )
-          }
+          for {
+            bspStatus <- bspStatusOpt
+            requestMonitor <- requestMonitorOpt
+          } yield new ServerLivenessMonitor(
+            requestMonitor,
+            () => server.workspaceBuildTargets(),
+            config.metalsToIdleTime,
+            config.pingInterval,
+            bspStatus,
+          )
 
         LauncherConnection(
           conn,

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

@@ -4,6 +4,7 @@ import java.util.concurrent.Executors
 import java.util.concurrent.ScheduledExecutorService
 import java.util.concurrent.ScheduledFuture
 import java.util.concurrent.TimeUnit
+import java.util.concurrent.atomic.AtomicBoolean
 import java.util.concurrent.atomic.AtomicReference
 
 import scala.concurrent.duration.Duration
@@ -23,7 +24,7 @@ trait RequestMonitor {
   def lastIncoming: Option[Long]
 }
 
-class RequestMonitorImpl extends RequestMonitor {
+class RequestMonitorImpl(bspStatus: BspStatus) extends RequestMonitor {
   @volatile private var lastOutgoing_ : Option[Long] = None
   @volatile private var lastIncoming_ : Option[Long] = None
 
@@ -44,7 +45,10 @@ class RequestMonitorImpl extends RequestMonitor {
     }
 
   private def outgoingMessage() = lastOutgoing_ = now
-  private def incomingMessage(): Unit = lastIncoming_ = now
+  private def incomingMessage(): Unit = {
+    bspStatus.connected()
+    lastIncoming_ = now
+  }
   private def now = Some(System.currentTimeMillis())
 
   def lastOutgoing: Option[Long] = lastOutgoing_
@@ -54,22 +58,14 @@ class RequestMonitorImpl extends RequestMonitor {
 class ServerLivenessMonitor(
     requestMonitor: RequestMonitor,
     ping: () => Unit,
-    client: MetalsLanguageClient,
     metalsIdleInterval: Duration,
     pingInterval: Duration,
-    serverName: String,
-    icons: Icons,
+    bspStatus: BspStatus,
 ) {
   private val state: AtomicReference[ServerLivenessMonitor.State] =
     new AtomicReference(ServerLivenessMonitor.Idle)
-  @volatile private var isServerResponsive = true
   val scheduler: ScheduledExecutorService = Executors.newScheduledThreadPool(1)
-  val connectedParams: MetalsStatusParams =
-    ServerLivenessMonitor.connectedParams(serverName, icons)
-  val noResponseParams: MetalsStatusParams =
-    ServerLivenessMonitor.noResponseParams(serverName, icons)
 
-  client.metalsStatus(connectedParams)
   scribe.debug("starting server liveness monitor")
 
   def runnable(): Runnable = new Runnable {
@@ -99,12 +95,9 @@ class ServerLivenessMonitor(
           case _ =>
         }
         if (currState == ServerLivenessMonitor.Running) {
-          if (notResponding && isServerResponsive) {
-            scribe.debug("server liveness monitor detected no response")
-            client.metalsStatus(noResponseParams)
-          } else if (!notResponding && !isServerResponsive)
-            client.metalsStatus(connectedParams)
-          isServerResponsive = !notResponding
+          if (notResponding) {
+            bspStatus.noResponse()
+          }
         }
         scribe.debug("server liveness monitor: pinging build server...")
         ping()
@@ -122,13 +115,13 @@ class ServerLivenessMonitor(
     TimeUnit.MILLISECONDS,
   )
 
-  def isBuildServerResponsive: Boolean = isServerResponsive
+  def isBuildServerResponsive: Boolean = bspStatus.isBuildServerResponsive
 
   def shutdown(): Unit = {
     scribe.debug("shutting down server liveness monitor")
     scheduled.cancel(true)
     scheduler.shutdown()
-    client.metalsStatus(ServerLivenessMonitor.disconnectedParams)
+    bspStatus.disconnected()
   }
 
   def getState: ServerLivenessMonitor.State = state.get()
@@ -147,6 +140,29 @@ object ServerLivenessMonitor {
   object FirstPing extends State
   object Running extends State
 
+}
+
+class BspStatus(
+    client: MetalsLanguageClient,
+    serverName: String,
+    icons: Icons,
+) {
+  private val isServerResponsive = new AtomicBoolean(false)
+
+  def connected(): Unit =
+    if (isServerResponsive.compareAndSet(false, true))
+      client.metalsStatus(BspStatus.connectedParams(serverName, icons))
+  def noResponse(): Unit =
+    if (isServerResponsive.compareAndSet(true, false)) {
+      scribe.debug("server liveness monitor detected no response")
+      client.metalsStatus(BspStatus.noResponseParams(serverName, icons))
+    }
+  def disconnected(): Unit = client.metalsStatus(BspStatus.disconnectedParams)
+
+  def isBuildServerResponsive: Boolean = isServerResponsive.get()
+}
+
+object BspStatus {
   def connectedParams(serverName: String, icons: Icons): MetalsStatusParams =
     MetalsStatusParams(
       s"$serverName ${icons.link}",
@@ -167,5 +183,4 @@ object ServerLivenessMonitor {
       command = ServerCommands.ConnectBuildServer.id,
       commandTooltip = "Reconnect.",
     ).withStatusType(StatusType.bsp)
-
 }

tests/unit/src/main/scala/tests/TestingClient.scala

@@ -16,14 +16,14 @@ import scala.meta.internal.builds.BspErrorHandler
 import scala.meta.internal.builds.BuildTool
 import scala.meta.internal.builds.BuildTools
 import scala.meta.internal.decorations.PublishDecorationsParams
+import scala.meta.internal.metals.BspStatus
 import scala.meta.internal.metals.Buffers
 import scala.meta.internal.metals.ClientCommands
 import scala.meta.internal.metals.FileOutOfScalaCliBspScope
 import scala.meta.internal.metals.Icons
 import scala.meta.internal.metals.Messages._
 import scala.meta.internal.metals.MetalsEnrichments._
 import scala.meta.internal.metals.ServerCommands
-import scala.meta.internal.metals.ServerLivenessMonitor
 import scala.meta.internal.metals.TextEdits
 import scala.meta.internal.metals.WorkspaceChoicePopup
 import scala.meta.internal.metals.clients.language.MetalsInputBoxParams
@@ -373,7 +373,7 @@ class TestingClient(workspace: AbsolutePath, val buffers: Buffers)
         ) {
           bspError
         } else if (
-          params.getMessage() == ServerLivenessMonitor
+          params.getMessage() == BspStatus
             .noResponseParams("Bill", Icons.default)
             .logMessage(Icons.default)
         ) {

tests/unit/src/test/scala/tests/ServerLivenessMonitorLspSuite.scala

@@ -2,11 +2,11 @@ package tests
 
 import scala.concurrent.duration.Duration
 
+import scala.meta.internal.metals.BspStatus
 import scala.meta.internal.metals.Icons
 import scala.meta.internal.metals.Messages
 import scala.meta.internal.metals.MetalsEnrichments._
 import scala.meta.internal.metals.MetalsServerConfig
-import scala.meta.internal.metals.ServerLivenessMonitor
 
 import bill.Bill
 import ch.epfl.scala.bsp4j.BuildTargetIdentifier
@@ -60,7 +60,7 @@ class ServerLivenessMonitorLspSuite extends BaseLspSuite("liveness-monitor") {
         )
       )
       _ = Thread.sleep(sleepTime)
-      noResponseParams = ServerLivenessMonitor.noResponseParams(
+      noResponseParams = BspStatus.noResponseParams(
         "Bill",
         Icons.default,
       )

tests/unit/src/test/scala/tests/ServerLivenessMonitorSuite.scala

@@ -8,6 +8,7 @@ import scala.concurrent.ExecutionContext
 import scala.concurrent.ExecutionContextExecutorService
 import scala.concurrent.duration.Duration
 
+import scala.meta.internal.metals.BspStatus
 import scala.meta.internal.metals.Icons
 import scala.meta.internal.metals.RequestMonitor
 import scala.meta.internal.metals.ServerLivenessMonitor
@@ -22,15 +23,15 @@ class ServerLivenessMonitorSuite extends BaseSuite {
     val pingInterval = Duration("3s")
     val server = new ResponsiveServer(pingInterval)
     val client = new CountMessageRequestsClient
+    val bspStatus = new BspStatus(client, "responsive-server", Icons.default)
     val livenessMonitor = new ServerLivenessMonitor(
       server,
       () => server.sendRequest(true),
-      client,
       metalsIdleInterval = pingInterval * 4,
       pingInterval,
-      "responsive-server",
-      Icons.default,
+      bspStatus,
     )
+    bspStatus.connected()
     Thread.sleep(pingInterval.toMillis * 3 / 2)
     assertEquals(livenessMonitor.getState, ServerLivenessMonitor.Idle)
     server.sendRequest(false)
@@ -46,6 +47,7 @@ class ServerLivenessMonitorSuite extends BaseSuite {
     server.sendRequest(false)
     assertEquals(livenessMonitor.getState, ServerLivenessMonitor.Running)
     assert(client.showMessageRequests == 0)
+    livenessMonitor.shutdown()
   }
 }
 
@@ -85,7 +87,9 @@ class CountMessageRequestsClient extends NoopLanguageClient {
   var showMessageRequests = 0
 
   override def metalsStatus(params: MetalsStatusParams): Unit =
-    if (params == ServerLivenessMonitor.disconnectedParams) {
+    if (
+      params == BspStatus.noResponseParams("responsive-server", Icons.default)
+    ) {
       showMessageRequests += 1
     }
 }