From fe3ffd1545992af9252eb17b99a5a43b672bb3e0 Mon Sep 17 00:00:00 2001
From: Evan Simkowitz <esimkowitz@users.noreply.github.com>
Date: Fri, 16 Feb 2024 12:14:05 -0800
Subject: [PATCH] Use IsEmpty rather than nullcheck for scbus types

* Use IsEmpty rather than nullcheck for scbus types
---
 wavesrv/pkg/scbus/modelupdate.go | 11 +++++++----
 wavesrv/pkg/scbus/scbus.go       |  4 ++--
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/wavesrv/pkg/scbus/modelupdate.go b/wavesrv/pkg/scbus/modelupdate.go
index 4e6f3605..0917f1aa 100644
--- a/wavesrv/pkg/scbus/modelupdate.go
+++ b/wavesrv/pkg/scbus/modelupdate.go
@@ -72,16 +72,16 @@ func (*ModelUpdatePacketType) GetType() string {
 	return ModelUpdateStr
 }
 
-func (mu *ModelUpdatePacketType) IsEmpty() bool {
-	if mu == nil || mu.Data == nil {
+func (upk *ModelUpdatePacketType) IsEmpty() bool {
+	if upk == nil {
 		return true
 	}
-	return mu.Data.IsEmpty()
+	return upk.Data.IsEmpty()
 }
 
 // Clean the ClientData in an update, if present
 func (upk *ModelUpdatePacketType) Clean() {
-	if upk == nil || upk.Data == nil {
+	if upk.IsEmpty() {
 		return
 	}
 	for _, item := range *(upk.Data) {
@@ -106,6 +106,9 @@ func MakeUpdatePacket() *ModelUpdatePacketType {
 
 // Returns the items in the update that are of type I
 func GetUpdateItems[I ModelUpdateItem](upk *ModelUpdatePacketType) []*I {
+	if upk.IsEmpty() {
+		return nil
+	}
 	ret := make([]*I, 0)
 	for _, item := range *(upk.Data) {
 		if i, ok := (item).(I); ok {
diff --git a/wavesrv/pkg/scbus/scbus.go b/wavesrv/pkg/scbus/scbus.go
index 7ce8d254..f9cefe29 100644
--- a/wavesrv/pkg/scbus/scbus.go
+++ b/wavesrv/pkg/scbus/scbus.go
@@ -110,7 +110,7 @@ func MakeUpdateBus() *UpdateBus {
 
 // Send an update to all channels in the collection
 func (bus *UpdateBus) DoUpdate(update UpdatePacket) {
-	if update == nil || update.IsEmpty() {
+	if update.IsEmpty() {
 		return
 	}
 	update.Clean()
@@ -128,7 +128,7 @@ func (bus *UpdateBus) DoUpdate(update UpdatePacket) {
 
 // Send a model update to only clients that are subscribed to the given screenId
 func (bus *UpdateBus) DoScreenUpdate(screenId string, update UpdatePacket) {
-	if update == nil {
+	if update.IsEmpty() {
 		return
 	}
 	update.Clean()