Support non backed enum & php 8.1

src/ActivityLogger.php

@@ -109,6 +109,10 @@ public function withProperties(mixed $properties): static
 
     public function withProperty(string $key, mixed $value): static
     {
+        if (is_object($value) && function_exists('enum_exists') && enum_exists(get_class($value))) {
+            $value = $value->value ?? $value->name;
+        }
+
         $this->getActivity()->properties = $this->getActivity()->properties->put($key, $value);
 
         return $this;

src/Traits/LogsActivity.php

@@ -366,6 +366,10 @@ public static function logChanges(Model $model): array
             if ($model->hasCast($attribute)) {
                 $cast = $model->getCasts()[$attribute];
 
+                if (function_exists('enum_exists') && enum_exists($cast)) {
+                    $changes[$attribute] = $model->getStorableEnumValue($changes[$attribute]);
+                }
+
                 if ($model->isCustomDateTimeCast($cast) || $model->isImmutableCustomDateTimeCast($cast)) {
                     $changes[$attribute] = $model->asDateTime($changes[$attribute])->format(explode(':', $cast, 2)[1]);
                 }

tests/AbleStoreNonBackedEnumTest.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace Spatie\Activitylog\Test;
+
+use Spatie\Activitylog\Test\Enum\NonBackedEnum;
+use Spatie\Activitylog\Test\Models\Activity;
+use Spatie\Activitylog\Test\Models\User;
+
+it('can store non backed enum', function () {
+    $description = 'ROLE LOG';
+
+    activity()
+        ->performedOn(User::first())
+        ->withProperty('role', NonBackedEnum::User)->log($description);
+
+    expect(Activity::query()->latest()->first()->description)->toEqual($description);
+});

tests/Enum/NonBackedEnum.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace Spatie\Activitylog\Test\Enum;
+
+enum NonBackedEnum
+{
+    case Admin;
+
+    case User;
+}