refactor config validation to remove some code duplication

Author: umbynos

cli/config/add.go

@@ -44,11 +44,7 @@ func initAddCommand() *cobra.Command {
 
 func runAddCommand(cmd *cobra.Command, args []string) {
 	key := args[0]
-	kind, err := typeOf(key)
-	if err != nil {
-		feedback.Error(err)
-		os.Exit(errorcodes.ErrGeneric)
-	}
+	kind := validateKey(key)
 
 	if kind != reflect.Slice {
 		feedback.Errorf(tr("The key '%[1]v' is not a list of items, can't add to it.\nMaybe use '%[2]s'?"), key, "config set")

cli/config/remove.go

@@ -44,11 +44,7 @@ func initRemoveCommand() *cobra.Command {
 
 func runRemoveCommand(cmd *cobra.Command, args []string) {
 	key := args[0]
-	kind, err := typeOf(key)
-	if err != nil {
-		feedback.Error(err)
-		os.Exit(errorcodes.ErrGeneric)
-	}
+	kind := validateKey(key)
 
 	if kind != reflect.Slice {
 		feedback.Errorf(tr("The key '%[1]v' is not a list of items, can't remove from it.\nMaybe use '%[2]s'?"), key, "config delete")

cli/config/set.go

@@ -47,11 +47,7 @@ func initSetCommand() *cobra.Command {
 
 func runSetCommand(cmd *cobra.Command, args []string) {
 	key := args[0]
-	kind, err := typeOf(key)
-	if err != nil {
-		feedback.Error(err)
-		os.Exit(errorcodes.ErrGeneric)
-	}
+	kind := validateKey(key)
 
 	if kind != reflect.Slice && len(args) > 2 {
 		feedback.Errorf(tr("Can't set multiple values in key %v"), key)

cli/config/validate.go

@@ -17,7 +17,11 @@ package config
 
 import (
 	"fmt"
+	"os"
 	"reflect"
+
+	"github.com/arduino/arduino-cli/cli/errorcodes"
+	"github.com/arduino/arduino-cli/cli/feedback"
 )
 
 var validMap = map[string]reflect.Kind{
@@ -46,3 +50,12 @@ func typeOf(key string) (reflect.Kind, error) {
 	}
 	return t, nil
 }
+
+func validateKey(key string) reflect.Kind {
+	kind, err := typeOf(key)
+	if err != nil {
+		feedback.Error(err)
+		os.Exit(errorcodes.ErrGeneric)
+	}
+	return kind
+}