regression: allow monitor to not require to specify the board if the port cannot be identified. (#2647)

* Allow default monitor settings if board can't be detected

* Improved messages at monitor startup

* Moving variable near their usage location

* Do not show warnings if the configs are provided by the user

* Added a couple of examples in the help

Author: cmaglie

Diff for: internal/cli/arguments/fqbn.go

@@ -80,8 +80,8 @@ func CalculateFQBNAndPort(ctx context.Context, portArgs *Port, fqbnArg *Fqbn, in
 		if portArgs == nil || portArgs.address == "" {
 			feedback.FatalError(&cmderrors.MissingFQBNError{}, feedback.ErrGeneric)
 		}
-		fqbn, port := portArgs.DetectFQBN(ctx, instance, srv)
-		if fqbn == "" {
+		fqbn, port, err := portArgs.DetectFQBN(ctx, instance, srv)
+		if err != nil {
 			feedback.FatalError(&cmderrors.MissingFQBNError{}, feedback.ErrGeneric)
 		}
 		return fqbn, port

Diff for: internal/cli/arguments/port.go

@@ -18,12 +18,12 @@ package arguments
 import (
 	"context"
 	"errors"
+	"fmt"
 	"time"
 
 	"github.com/arduino/arduino-cli/commands"
 	"github.com/arduino/arduino-cli/commands/cmderrors"
 	f "github.com/arduino/arduino-cli/internal/algorithms"
-	"github.com/arduino/arduino-cli/internal/cli/feedback"
 	"github.com/arduino/arduino-cli/internal/i18n"
 	rpc "github.com/arduino/arduino-cli/rpc/cc/arduino/cli/commands/v1"
 	"github.com/sirupsen/logrus"
@@ -132,13 +132,13 @@ func (p *Port) GetSearchTimeout() time.Duration {
 // DetectFQBN tries to identify the board connected to the port and returns the
 // discovered Port object together with the FQBN. If the port does not match
 // exactly 1 board,
-func (p *Port) DetectFQBN(ctx context.Context, inst *rpc.Instance, srv rpc.ArduinoCoreServiceServer) (string, *rpc.Port) {
+func (p *Port) DetectFQBN(ctx context.Context, inst *rpc.Instance, srv rpc.ArduinoCoreServiceServer) (string, *rpc.Port, error) {
 	detectedPorts, err := srv.BoardList(ctx, &rpc.BoardListRequest{
 		Instance: inst,
 		Timeout:  p.timeout.Get().Milliseconds(),
 	})
 	if err != nil {
-		feedback.Fatal(i18n.Tr("Error during FQBN detection: %v", err), feedback.ErrGeneric)
+		return "", nil, fmt.Errorf("%s: %w", i18n.Tr("Error during board detection"), err)
 	}
 	for _, detectedPort := range detectedPorts.GetPorts() {
 		port := detectedPort.GetPort()
@@ -149,14 +149,14 @@ func (p *Port) DetectFQBN(ctx context.Context, inst *rpc.Instance, srv rpc.Ardui
 			continue
 		}
 		if len(detectedPort.GetMatchingBoards()) > 1 {
-			feedback.FatalError(&cmderrors.MultipleBoardsDetectedError{Port: port}, feedback.ErrBadArgument)
+			return "", nil, &cmderrors.MultipleBoardsDetectedError{Port: port}
 		}
 		if len(detectedPort.GetMatchingBoards()) == 0 {
-			feedback.FatalError(&cmderrors.NoBoardsDetectedError{Port: port}, feedback.ErrBadArgument)
+			return "", nil, &cmderrors.NoBoardsDetectedError{Port: port}
 		}
-		return detectedPort.GetMatchingBoards()[0].GetFqbn(), port
+		return detectedPort.GetMatchingBoards()[0].GetFqbn(), port, nil
 	}
-	return "", nil
+	return "", nil, &cmderrors.NoBoardsDetectedError{Port: &rpc.Port{Address: p.address, Protocol: p.protocol}}
 }
 
 // IsPortFlagSet returns true if the port address is provided

Diff for: internal/cli/monitor/monitor.go

@@ -19,9 +19,9 @@ import (
 	"bytes"
 	"context"
 	"errors"
-	"fmt"
 	"io"
 	"os"
+	"slices"
 	"sort"
 	"strings"
 	"time"
@@ -34,6 +34,7 @@ import (
 	"github.com/arduino/arduino-cli/internal/cli/instance"
 	"github.com/arduino/arduino-cli/internal/i18n"
 	rpc "github.com/arduino/arduino-cli/rpc/cc/arduino/cli/commands/v1"
+	"github.com/arduino/go-properties-orderedmap"
 	"github.com/fatih/color"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
@@ -58,6 +59,8 @@ func NewCommand(srv rpc.ArduinoCoreServiceServer) *cobra.Command {
 		Long:  i18n.Tr("Open a communication port with a board."),
 		Example: "" +
 			"  " + os.Args[0] + " monitor -p /dev/ttyACM0\n" +
+			"  " + os.Args[0] + " monitor -p /dev/ttyACM0 -b arduino:avr:uno\n" +
+			"  " + os.Args[0] + " monitor -p /dev/ttyACM0 --config 115200\n" +
 			"  " + os.Args[0] + " monitor -p /dev/ttyACM0 --describe",
 		Run: func(cmd *cobra.Command, args []string) {
 			sketchPath := ""
@@ -89,13 +92,6 @@ func runMonitorCmd(
 		quiet = true
 	}
 
-	var (
-		inst                         *rpc.Instance
-		profile                      *rpc.SketchProfile
-		fqbn                         string
-		defaultPort, defaultProtocol string
-	)
-
 	// Flags takes maximum precedence over sketch.yaml
 	// If {--port --fqbn --profile} are set we ignore the profile.
 	// If both {--port --profile} are set we read the fqbn in the following order: profile -> default_fqbn -> discovery
@@ -110,9 +106,9 @@ func runMonitorCmd(
 		)
 	}
 	sketch := resp.GetSketch()
-	if sketch != nil {
-		defaultPort, defaultProtocol = sketch.GetDefaultPort(), sketch.GetDefaultProtocol()
-	}
+
+	var inst *rpc.Instance
+	var profile *rpc.SketchProfile
 	if fqbnArg.String() == "" {
 		if profileArg.Get() == "" {
 			inst, profile = instance.CreateAndInitWithProfile(ctx, srv, sketch.GetDefaultProfile().GetName(), sketchPath)
@@ -123,11 +119,13 @@ func runMonitorCmd(
 	if inst == nil {
 		inst = instance.CreateAndInit(ctx, srv)
 	}
+
 	// Priority on how to retrieve the fqbn
 	// 1. from flag
 	// 2. from profile
 	// 3. from default_fqbn specified in the sketch.yaml
 	// 4. try to detect from the port
+	var fqbn string
 	switch {
 	case fqbnArg.String() != "":
 		fqbn = fqbnArg.String()
@@ -136,15 +134,19 @@ func runMonitorCmd(
 	case sketch.GetDefaultFqbn() != "":
 		fqbn = sketch.GetDefaultFqbn()
 	default:
-		fqbn, _ = portArgs.DetectFQBN(ctx, inst, srv)
+		fqbn, _, _ = portArgs.DetectFQBN(ctx, inst, srv)
 	}
 
+	var defaultPort, defaultProtocol string
+	if sketch != nil {
+		defaultPort, defaultProtocol = sketch.GetDefaultPort(), sketch.GetDefaultProtocol()
+	}
 	portAddress, portProtocol, err := portArgs.GetPortAddressAndProtocol(ctx, inst, srv, defaultPort, defaultProtocol)
 	if err != nil {
 		feedback.FatalError(err, feedback.ErrGeneric)
 	}
 
-	enumerateResp, err := srv.EnumerateMonitorPortSettings(ctx, &rpc.EnumerateMonitorPortSettingsRequest{
+	defaultSettings, err := srv.EnumerateMonitorPortSettings(ctx, &rpc.EnumerateMonitorPortSettingsRequest{
 		Instance:     inst,
 		PortProtocol: portProtocol,
 		Fqbn:         fqbn,
@@ -153,14 +155,19 @@ func runMonitorCmd(
 		feedback.Fatal(i18n.Tr("Error getting port settings details: %s", err), feedback.ErrGeneric)
 	}
 	if describe {
-		settings := make([]*result.MonitorPortSettingDescriptor, len(enumerateResp.GetSettings()))
-		for i, v := range enumerateResp.GetSettings() {
+		settings := make([]*result.MonitorPortSettingDescriptor, len(defaultSettings.GetSettings()))
+		for i, v := range defaultSettings.GetSettings() {
 			settings[i] = result.NewMonitorPortSettingDescriptor(v)
 		}
 		feedback.PrintResult(&detailsResult{Settings: settings})
 		return
 	}
 
+	actualConfigurationLabels := properties.NewMap()
+	for _, setting := range defaultSettings.GetSettings() {
+		actualConfigurationLabels.Set(setting.GetSettingId(), setting.GetValue())
+	}
+
 	configuration := &rpc.MonitorPortConfiguration{}
 	if len(configs) > 0 {
 		for _, config := range configs {
@@ -173,7 +180,7 @@ func runMonitorCmd(
 			}
 
 			var setting *rpc.MonitorPortSettingDescriptor
-			for _, s := range enumerateResp.GetSettings() {
+			for _, s := range defaultSettings.GetSettings() {
 				if k == "" {
 					if contains(s.GetEnumValues(), v) {
 						setting = s
@@ -196,10 +203,7 @@ func runMonitorCmd(
 				SettingId: setting.GetSettingId(),
 				Value:     v,
 			})
-			if !quiet {
-				feedback.Print(i18n.Tr("Monitor port settings:"))
-				feedback.Print(fmt.Sprintf("%s=%s", setting.GetSettingId(), v))
-			}
+			actualConfigurationLabels.Set(setting.GetSettingId(), v)
 		}
 	}
 
@@ -229,7 +233,6 @@ func runMonitorCmd(
 		}
 		ttyIn = io.TeeReader(ttyIn, ctrlCDetector)
 	}
-
 	monitorServer, portProxy := commands.MonitorServerToReadWriteCloser(ctx, &rpc.MonitorPortOpenRequest{
 		Instance:          inst,
 		Port:              &rpc.Port{Address: portAddress, Protocol: portProtocol},
@@ -238,6 +241,21 @@ func runMonitorCmd(
 	})
 	go func() {
 		if !quiet {
+			if len(configs) == 0 {
+				if fqbn != "" {
+					feedback.Print(i18n.Tr("Using default monitor configuration for board: %s", fqbn))
+				} else if portProtocol == "serial" {
+					feedback.Print(i18n.Tr("Using generic monitor configuration.\nWARNING: Your board may require different settings to work!\n"))
+				}
+			}
+			feedback.Print(i18n.Tr("Monitor port settings:"))
+			keys := actualConfigurationLabels.Keys()
+			slices.Sort(keys)
+			for _, k := range keys {
+				feedback.Printf("  %s=%s", k, actualConfigurationLabels.Get(k))
+			}
+			feedback.Print("")
+
 			feedback.Print(i18n.Tr("Connecting to %s. Press CTRL-C to exit.", portAddress))
 		}
 		if err := srv.Monitor(monitorServer); err != nil {