Report discovery start errors

arduino/discovery/discoverymanager/discoverymanager.go

@@ -81,11 +81,11 @@ func (dm *DiscoveryManager) IDs() []string {
 
 // Start starts all the discoveries in this DiscoveryManager.
 // If the discoveries are already running, this function does nothing.
-func (dm *DiscoveryManager) Start() {
+func (dm *DiscoveryManager) Start() []error {
 	dm.discoveriesMutex.Lock()
 	defer dm.discoveriesMutex.Unlock()
 	if dm.discoveriesRunning {
-		return
+		return nil
 	}
 
 	go func() {
@@ -95,16 +95,25 @@ func (dm *DiscoveryManager) Start() {
 		}
 	}()
 
+	errs := []error{}
+	var errsLock sync.Mutex
+
 	var wg sync.WaitGroup
 	for _, d := range dm.discoveries {
 		wg.Add(1)
 		go func(d *discovery.PluggableDiscovery) {
-			dm.startDiscovery(d)
+			if err := dm.startDiscovery(d); err != nil {
+				errsLock.Lock()
+				errs = append(errs, err)
+				errsLock.Unlock()
+			}
 			wg.Done()
 		}(d)
 	}
 	wg.Wait()
 	dm.discoveriesRunning = true
+
+	return errs
 }
 
 // Add adds a discovery to the list of managed discoveries

cli/arguments/completion.go

@@ -178,7 +178,7 @@ func GetInstallableLibs() []string {
 func GetConnectedBoards() []string {
 	inst := instance.CreateAndInit()
 
-	list, _ := board.List(&rpc.BoardListRequest{
+	list, _, _ := board.List(&rpc.BoardListRequest{
 		Instance: inst,
 	})
 	var res []string

cli/arguments/port.go

@@ -146,7 +146,7 @@ func (p *Port) GetSearchTimeout() time.Duration {
 // discovered Port object together with the FQBN. If the port does not match
 // exactly 1 board,
 func (p *Port) DetectFQBN(inst *rpc.Instance) (string, *rpc.Port) {
-	detectedPorts, err := board.List(&rpc.BoardListRequest{
+	detectedPorts, _, err := board.List(&rpc.BoardListRequest{
 		Instance: inst,
 		Timeout:  p.timeout.Get().Milliseconds(),
 	})

cli/board/list.go

@@ -64,13 +64,16 @@ func runListCommand(cmd *cobra.Command, args []string) {
 		os.Exit(0)
 	}
 
-	ports, err := board.List(&rpc.BoardListRequest{
+	ports, discvoeryErrors, err := board.List(&rpc.BoardListRequest{
 		Instance: inst,
 		Timeout:  timeoutArg.Get().Milliseconds(),
 	})
 	if err != nil {
 		feedback.Errorf(tr("Error detecting boards: %v"), err)
 	}
+	for _, err := range discvoeryErrors {
+		feedback.Errorf(tr("Error starting discovery: %v"), err)
+	}
 	feedback.PrintResult(result{ports})
 }
 

commands/board/list.go

@@ -177,21 +177,21 @@ func identify(pm *packagemanager.PackageManager, port *discovery.Port) ([]*rpc.B
 // List returns a list of boards found by the loaded discoveries.
 // In case of errors partial results from discoveries that didn't fail
 // are returned.
-func List(req *rpc.BoardListRequest) (r []*rpc.DetectedPort, e error) {
+func List(req *rpc.BoardListRequest) (r []*rpc.DetectedPort, discoveryStartErrors []error, e error) {
 	pm := commands.GetPackageManager(req.GetInstance().Id)
 	if pm == nil {
-		return nil, &arduino.InvalidInstanceError{}
+		return nil, nil, &arduino.InvalidInstanceError{}
 	}
 
 	dm := pm.DiscoveryManager()
-	dm.Start()
+	discoveryStartErrors = dm.Start()
 	time.Sleep(time.Duration(req.GetTimeout()) * time.Millisecond)
 
 	retVal := []*rpc.DetectedPort{}
 	for _, port := range dm.List() {
 		boards, err := identify(pm, port)
 		if err != nil {
-			return nil, err
+			return nil, discoveryStartErrors, err
 		}
 
 		// boards slice can be empty at this point if neither the cores nor the
@@ -202,7 +202,7 @@ func List(req *rpc.BoardListRequest) (r []*rpc.DetectedPort, e error) {
 		}
 		retVal = append(retVal, b)
 	}
-	return retVal, nil
+	return retVal, discoveryStartErrors, nil
 }
 
 // Watch returns a channel that receives boards connection and disconnection events.

commands/daemon/daemon.go

@@ -67,7 +67,7 @@ func (s *ArduinoCoreServerImpl) BoardDetails(ctx context.Context, req *rpc.Board
 
 // BoardList FIXMEDOC
 func (s *ArduinoCoreServerImpl) BoardList(ctx context.Context, req *rpc.BoardListRequest) (*rpc.BoardListResponse, error) {
-	ports, err := board.List(req)
+	ports, _, err := board.List(req)
 	if err != nil {
 		return nil, convertErrorToRPCStatus(err)
 	}