add comments

OneSignalSDK/onesignal/notifications/src/main/AndroidManifest.xml

@@ -65,6 +65,7 @@
             </intent-filter>
         </service>
 
+        <!-- CAUTION: OneSignal backend includes the activity name in the payload, modifying the name without sync may result in notification click not firing -->
         <activity
             android:name="com.onesignal.NotificationOpenedActivityHMS"
             android:noHistory="true"

OneSignalSDK/onesignal/notifications/src/main/java/com/onesignal/NotificationOpenedActivityHMS.kt

@@ -25,6 +25,7 @@
  * THE SOFTWARE.
  */
 package com.onesignal
+// OneSignal backend includes the activity name in the payload, modifying the namespace may result in notification click not firing
 
 import android.app.Activity
 import android.content.Intent

OneSignalSDK/onesignal/notifications/src/test/java/com/onesignal/notifications/ClassPathTests.kt

@@ -0,0 +1,15 @@
+package com.onesignal.notifications
+
+import io.kotest.core.spec.style.FunSpec
+import org.junit.jupiter.api.assertDoesNotThrow
+
+class ClassPathTests : FunSpec({
+    test("ensure the class path for NotificationOpenedActivityHMS.kt is in consistent with that returned by the backend service") {
+        // The test will fail if the classpath is changed by accident.
+        // If the change is intentional and corresponds with the backend update, modify or remove this test accordingly.
+        val fullClassName = "com.onesignal.NotificationOpenedActivityHMS"
+        assertDoesNotThrow {
+            Class.forName(fullClassName)
+        }
+    }
+})