Check for errors and forward on exec command (#227)

fix #226

cmd/exec.go

@@ -1,6 +1,8 @@
 package cmd
 
 import (
+	"fmt"
+
 	"github.com/cupcakearmy/autorestic/internal"
 	"github.com/cupcakearmy/autorestic/internal/colors"
 	"github.com/cupcakearmy/autorestic/internal/lock"
@@ -18,10 +20,23 @@ var execCmd = &cobra.Command{
 
 		selected, err := internal.GetAllOrSelected(cmd, true)
 		CheckErr(err)
+
+		var errors []error
 		for _, name := range selected {
 			colors.PrimaryPrint("  Executing on \"%s\"  ", name)
 			backend, _ := internal.GetBackend(name)
-			backend.Exec(args)
+			err := backend.Exec(args)
+			if err != nil {
+				errors = append(errors, err)
+			}
+		}
+
+		if len(errors) > 0 {
+			for _, err := range errors {
+				colors.Error.Printf("%s\n\n", err)
+			}
+
+			CheckErr(fmt.Errorf("%d errors were found", len(errors)))
 		}
 	},
 }