move to namespace + add serialization extensions

Editor.meta

@@ -0,0 +1,8 @@
+fileFormatVersion: 2
+guid: 2b210ff3d17b2814e81a315ad8f9bf32
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Editor/SerializationExtentions.cs

@@ -0,0 +1,32 @@
+using System;
+using UnityEditor;
+
+namespace NEG.Utils.Serialization
+{
+    public static class SerializationExtentions
+    {
+        public static SerializedProperty FindAutoProperty(this SerializedObject @this, string name)
+        {
+            return @this.FindProperty(GetBackingFieldName(name));
+        }
+
+        public static SerializedProperty FindAutoPropertyRelative(this SerializedProperty @this, string name)
+        {
+            return @this.FindPropertyRelative(GetBackingFieldName(name));
+        }
+
+        private static string GetBackingFieldName(string name)
+        {
+#if NET_STANDARD || NET_STANDARD_2_1
+        return string.Create(1/*<*/ + name.Length + 16/*>k__BackingField*/, name, static (span, name) =>
+        {
+            span[0] = '<';
+            name.AsSpan().CopyTo(span[1..]);
+            ">k__BackingField".AsSpan().CopyTo(span[(name.Length + 1)..]);
+        });
+#else
+            return '<' + name + ">k__BackingField";
+#endif
+        }
+    }
+}

Editor/SerializationExtentions.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 0a42993224bbc704dbe244661de48913
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

RequireInterface/Editor/RequireInterfaceDrawer.cs

@@ -3,6 +3,9 @@ using UnityEditor;
 /// <summary>
 /// Drawer for the RequireInterface attribute.
 /// </summary>
+
+namespace NEG.Utils
+{
     [CustomPropertyDrawer(typeof(RequireInterfaceAttribute))]
     public class RequireInterfaceDrawer : PropertyDrawer
     {
@@ -39,3 +42,4 @@ public class RequireInterfaceDrawer : PropertyDrawer
             }
         }
     }
+}

RequireInterface/RequireInterfaceAttribute.cs

@@ -2,6 +2,9 @@ using UnityEngine;
 /// <summary>
 /// Attribute that require implementation of the provided interface.
 /// </summary>
+
+namespace NEG.Utils
+{
     public class RequireInterfaceAttribute : PropertyAttribute
     {
         // Interface type.
@@ -15,3 +18,4 @@ public class RequireInterfaceAttribute : PropertyAttribute
             this.requiredType = type;
         }
     }
+}