Always get a fresh AppInstance instance when testing topic subscriptions

tests/Integration/Messaging/AppInstanceTest.php

@@ -5,6 +5,7 @@
 namespace Kreait\Firebase\Tests\Integration\Messaging;
 
 use Kreait\Firebase\Contract\Messaging;
+use Kreait\Firebase\Messaging\AppInstance;
 use Kreait\Firebase\Messaging\RegistrationToken;
 use Kreait\Firebase\Tests\IntegrationTestCase;
 use PHPUnit\Framework\Attributes\Test;
@@ -37,18 +38,28 @@ public function itIsSubscribedToTopics(): void
         $this->messaging->subscribeToTopic($secondTopic, RegistrationToken::fromValue($token)); // Lazy registration token test
         $this->messaging->subscribeToTopic($thirdTopic, $token);
 
-        $instance = $this->messaging->getAppInstance($token);
-
-        $this->assertTrue($instance->isSubscribedToTopic($firstTopic));
-        $this->assertTrue($instance->isSubscribedToTopic($secondTopic));
+        $this->assertTrue($this->appInstance($token)->isSubscribedToTopic($firstTopic));
+        $this->assertTrue($this->appInstance($token)->isSubscribedToTopic($secondTopic));
+        $this->assertTrue($this->appInstance($token)->isSubscribedToTopic($thirdTopic));
 
         $this->messaging->unsubscribeFromTopic($firstTopic, $token);
+        $this->assertFalse($this->appInstance($token)->isSubscribedToTopic($firstTopic));
+        $this->assertTrue($this->appInstance($token)->isSubscribedToTopic($secondTopic));
+        $this->assertTrue($this->appInstance($token)->isSubscribedToTopic($thirdTopic));
+
         $this->messaging->unsubscribeFromTopic($secondTopic, $token);
-        $this->messaging->unsubscribeFromAllTopics($token);
+        $this->assertFalse($this->appInstance($token)->isSubscribedToTopic($secondTopic));
+        $this->assertTrue($this->appInstance($token)->isSubscribedToTopic($thirdTopic));
 
-        $instance = $this->messaging->getAppInstance($token);
+        $this->messaging->unsubscribeFromAllTopics($token);
+        $this->assertFalse($this->appInstance($token)->isSubscribedToTopic($thirdTopic));
+    }
 
-        $this->assertFalse($instance->isSubscribedToTopic($firstTopic));
-        $this->assertFalse($instance->isSubscribedToTopic($secondTopic));
+    /**
+     * @param non-empty-string $registrationToken
+     */
+    private function appInstance(string $registrationToken): AppInstance
+    {
+        return $this->messaging->getAppInstance($registrationToken);
     }
 }