[1.x] fix unsupported events result in errors (#417)

- Fix #416

src/Events/EventFactory.php

@@ -42,10 +42,14 @@ public function create(ServerNotification $notification): PurchaseEvent
             ->lower()
             ->studly()
             ->prepend(self::NAMESPACES[$provider].'\\');
-        assert(class_exists($className), new LogicException("Class $className does not exist"));
+
+        if (! class_exists($className)) {
+            return new FallbackEvent($notification);
+        }
+
         assert(
-            is_subclass_of($className, PurchaseEvent::class),
-            new LogicException("Class $className is not a subclass of PurchaseEvent")
+            is_a($className, PurchaseEvent::class, true),
+            new LogicException("Invalid event class: $className")
         );
 
         return new $className($notification);

src/Events/FallbackEvent.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Imdhemy\Purchases\Events;
+
+final class FallbackEvent extends PurchaseEvent
+{
+}

tests/Events/EventFactoryTest.php

@@ -20,6 +20,7 @@
 use Imdhemy\Purchases\Events\AppStore\Refund;
 use Imdhemy\Purchases\Events\AppStore\Revoke;
 use Imdhemy\Purchases\Events\EventFactory;
+use Imdhemy\Purchases\Events\FallbackEvent;
 use Imdhemy\Purchases\Events\GooglePlay\SubscriptionCanceled;
 use Imdhemy\Purchases\Events\GooglePlay\SubscriptionDeferred;
 use Imdhemy\Purchases\Events\GooglePlay\SubscriptionExpired;
@@ -109,6 +110,10 @@ public function googlePlayEventsProvider(): array
                 GoogleNotification::SUBSCRIPTION_EXPIRED,
                 SubscriptionExpired::class,
             ],
+            [
+                'InvalidType',
+                FallbackEvent::class,
+            ],
         ];
 
         foreach ($data as &$item) {
@@ -170,6 +175,10 @@ public function appStoreEventsProvider(): array
                 AppstoreNotification::REVOKE,
                 Revoke::class,
             ],
+            [
+                'InvalidType',
+                FallbackEvent::class,
+            ],
         ];
 
         foreach ($data as &$item) {