Clean up internal robot error passing

connection.go

@@ -1,8 +1,6 @@
 package gobot
 
 import (
-	"errors"
-	"fmt"
 	"log"
 )
 
@@ -29,8 +27,7 @@ func (c *connections) Each(f func(Connection)) {
 }
 
 // Start initializes all the connections.
-func (c *connections) Start() error {
-	var err error
+func (c *connections) Start() (err error) {
 	log.Println("Starting connections...")
 	for _, connection := range *c {
 		info := "Starting connection " + connection.Name()
@@ -40,11 +37,10 @@ func (c *connections) Start() error {
 		log.Println(info + "...")
 		err = connection.Connect()
 		if err != nil {
-			err = errors.New(fmt.Sprintf("Could not start connection: %v", err))
-			break
+			return
 		}
 	}
-	return err
+	return
 }
 
 // Finalize finishes all the connections.

gobot.go

@@ -56,14 +56,17 @@ func (g *Gobot) Command(name string) func(map[string]interface{}) interface{} {
 }
 
 // Start runs the main Gobot event loop
-func (g *Gobot) Start() error {
-	err := g.robots.Start()
+func (g *Gobot) Start() (err error) {
+	err = g.robots.Start()
 	if err != nil {
-		return err
+		log.Println(err)
 	}
 
 	c := make(chan os.Signal, 1)
 	g.trap(c)
+	if err != nil {
+		c <- os.Interrupt
+	}
 
 	// waiting for interrupt coming on the channel
 	_ = <-c
@@ -72,7 +75,7 @@ func (g *Gobot) Start() error {
 		r.Devices().Halt()
 		r.Connections().Finalize()
 	})
-	return nil
+	return err
 }
 
 // Robots fetch all robots associated with this Gobot instance.

robot.go

@@ -1,7 +1,6 @@
 package gobot
 
 import (
-	"errors"
 	"fmt"
 	"log"
 )
@@ -34,14 +33,14 @@ func (r *robots) Len() int {
 
 // Start initialises the event loop. All robots that were added will
 // be automtically started as a result of this call.
-func (r *robots) Start() error {
+func (r *robots) Start() (err error) {
 	for _, robot := range *r {
-		err := robot.Start()
+		err = robot.Start()
 		if err != nil {
-			return err
+			return
 		}
 	}
-	return nil
+	return
 }
 
 // Each enumerates thru the robots and calls specified function
@@ -85,7 +84,7 @@ func NewRobot(name string, v ...interface{}) *Robot {
 		case func():
 			r.Work = v[i].(func())
 		default:
-			fmt.Println("Unknown argument passed to NewRobot")
+			log.Println("Unknown argument passed to NewRobot")
 		}
 	}
 
@@ -110,13 +109,13 @@ func (r *Robot) Command(name string) func(map[string]interface{}) interface{} {
 // Start a robot instance and runs it's work function if any. You should not
 // need to manually start a robot if already part of a Gobot application as the
 // robot will be automatically started for you.
-func (r *Robot) Start() error {
+func (r *Robot) Start() (err error) {
 	log.Println("Starting Robot", r.Name, "...")
-	if err := r.Connections().Start(); err != nil {
-		return errors.New(fmt.Sprintf("Could not start connections: %v", err))
+	if err = r.Connections().Start(); err != nil {
+		return
 	}
-	if err := r.Devices().Start(); err != nil {
-		return errors.New(fmt.Sprintf("Could not start devices %v", err))
+	if err = r.Devices().Start(); err != nil {
+		return err
 	}
 	if r.Work != nil {
 		log.Println("Starting work...")