From cc29e97fa30cdcbd12ff1b060419f8e2bf6711a5 Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Thu, 7 Oct 2021 09:29:50 +0200
Subject: [PATCH] Fix automatic properties serialization bug

---
 .../Bindings/BindingsGenerator.Cpp.cs           | 17 +++++++++++++++--
 Source/Tools/Flax.Build/Bindings/TypeInfo.cs    |  5 +++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/Source/Tools/Flax.Build/Bindings/BindingsGenerator.Cpp.cs b/Source/Tools/Flax.Build/Bindings/BindingsGenerator.Cpp.cs
index 5daebbeb1..9569c15c5 100644
--- a/Source/Tools/Flax.Build/Bindings/BindingsGenerator.Cpp.cs
+++ b/Source/Tools/Flax.Build/Bindings/BindingsGenerator.Cpp.cs
@@ -1323,8 +1323,21 @@ namespace Flax.Build.Bindings
                     if (GenerateCppAutoSerializationSkip(buildData, typeInfo, propertyInfo, propertyInfo.Type))
                         continue;
 
-                    var typeHint = GenerateCppAutoSerializationDefineType(buildData, contents, moduleInfo, typeInfo, propertyInfo.Type, propertyInfo);
-                    contents.Append($"    SERIALIZE{typeHint}_MEMBER({propertyInfo.Name}, {propertyInfo.Getter.Name}());").AppendLine();
+                    contents.Append("    {");
+                    contents.Append(" const auto");
+                    if (propertyInfo.Getter.ReturnType.IsConstRef)
+                        contents.Append('&');
+                    contents.Append($" value = {propertyInfo.Getter.Name}();");
+                    contents.Append(" if (other) { const auto");
+                    if (propertyInfo.Getter.ReturnType.IsConstRef)
+                        contents.Append('&');
+                    contents.Append($" otherValue = other->{propertyInfo.Getter.Name}();");
+                    contents.Append(" if (Serialization::ShouldSerialize(value, &otherValue)) { ");
+                    contents.Append($"stream.JKEY(\"{propertyInfo.Name}\"); Serialization::Serialize(stream, value, &otherValue);");
+                    contents.Append(" } } else if (Serialization::ShouldSerialize(value, nullptr)) { ");
+                    contents.Append($"stream.JKEY(\"{propertyInfo.Name}\"); Serialization::Serialize(stream, value, nullptr);");
+                    contents.Append(" }");
+                    contents.Append('}').AppendLine();
                     CppAutoSerializeProperties.Add(propertyInfo);
                 }
             }
diff --git a/Source/Tools/Flax.Build/Bindings/TypeInfo.cs b/Source/Tools/Flax.Build/Bindings/TypeInfo.cs
index bfead9218..350015507 100644
--- a/Source/Tools/Flax.Build/Bindings/TypeInfo.cs
+++ b/Source/Tools/Flax.Build/Bindings/TypeInfo.cs
@@ -28,6 +28,11 @@ namespace Flax.Build.Bindings
         /// </summary>
         public bool IsVoid => Type == "void" && !IsPtr;
 
+        /// <summary>
+        /// Gets a value indicating whether this type is constant reference to a value.
+        /// </summary>
+        public bool IsConstRef => IsRef && IsConst;
+
         /// <summary>
         /// Gets a value indicating whether this type is POD (plain old data).
         /// </summary>