fix: Report any unknown options found on the command line.

Card ID: CCT-524

The rhc subcommands, connect, disconnect and status ignore any
unknown options given. This PR will fix this by returning an
error when any unknown options are found.

main.go

@@ -253,7 +253,7 @@ func beforeConnectAction(ctx *cli.Context) error {
 		}
 	}
 
-	return nil
+	return checkForUnknownArgs(ctx)
 }
 
 // connectAction tries to register system against Red Hat Subscription Management,
@@ -487,7 +487,12 @@ func (connectResult ConnectResult) Error() string {
 
 // beforeDisconnectAction ensures the used has supplied a correct `--format` flag
 func beforeDisconnectAction(ctx *cli.Context) error {
-	return setupFormatOption(ctx)
+	err := setupFormatOption(ctx)
+	if err != nil {
+		return err
+	}
+
+	return checkForUnknownArgs(ctx)
 }
 
 // interactivePrintf is method for printing human-readable output. It suppresses output, when
@@ -648,7 +653,12 @@ func printJSONStatus(systemStatus *SystemStatus) error {
 
 // beforeStatusAction ensures the user has supplied a correct `--format` flag.
 func beforeStatusAction(ctx *cli.Context) error {
-	return setupFormatOption(ctx)
+	err := setupFormatOption(ctx)
+	if err != nil {
+		return err
+	}
+
+	return checkForUnknownArgs(ctx)
 }
 
 // statusAction tries to print status of system. It means that it gives

util.go

@@ -154,3 +154,12 @@ func getLocale() string {
 	locale := os.Getenv("LANG")
 	return locale
 }
+
+// checkForUnknownArgs returns an error if any unknown arguments are present.
+func checkForUnknownArgs(ctx *cli.Context) error {
+	if ctx.Args().Len() != 0 {
+		return fmt.Errorf("error: unknown option(s): %s",
+			strings.Join(ctx.Args().Slice(), " "))
+	}
+	return nil
+}