fleetctl: print error when units were not found in registry

fleetctl/destroy.go

@@ -46,6 +46,11 @@ func runDestroyUnits(args []string) (exit int) {
 		return 1
 	}
 
+	if len(units) == 0 {
+		stderr("Units not found in registry")
+		return 0
+	}
+
 	for _, v := range units {
 		err := cAPI.DestroyUnit(v.Name)
 		if err != nil {

fleetctl/stop.go

@@ -63,6 +63,11 @@ func runStopUnit(args []string) (exit int) {
 		return 1
 	}
 
+	if len(units) == 0 {
+		stderr("Units not found in registry")
+		return 0
+	}
+
 	stopping := make([]string, 0)
 	for _, u := range units {
 		if !suToGlobal(u) {

fleetctl/unload.go

@@ -47,6 +47,11 @@ func runUnloadUnit(args []string) (exit int) {
 		return 1
 	}
 
+	if len(units) == 0 {
+		stderr("Units not found in registry")
+		return 0
+	}
+
 	wait := make([]string, 0)
 	for _, s := range units {
 		if !suToGlobal(s) {