818: Avoid "list is empty" (due to a crash in load())

Author: Lakoja

app/src/main/java/com/keylesspalace/tusky/components/notifications/NotificationsPagingSource.kt

@@ -95,12 +95,13 @@ class NotificationsPagingSource @Inject constructor(
 
             // TODO this is the only location with the "raw" data for answering the TODO in NotificationsViewModel.hasNewestNotificationId()?
             //   However the heuristic there would need (at least) the full range of notification ids here (so multiple calls to this method)?
-            val apiNotificationIds = response.body()!!.map { it.id }
-            Log.w(TAG, "Got notifications from api "+apiNotificationIds.first()+"-"+apiNotificationIds.last())
+            val notificationList = response.body()!!
+            val apiNotificationIds = notificationList.map { it.id }
+            Log.w(TAG, (if (params is LoadParams.Refresh) "R" else "A/P") +" Got notifications from api "+apiNotificationIds.firstOrNull()+"-"+apiNotificationIds.lastOrNull())
 
             val links = Links.from(response.headers()["link"])
             return LoadResult.Page(
-                data = response.body()!!,
+                data = notificationList,
                 nextKey = links.next,
                 prevKey = links.prev
             )

app/src/main/java/com/keylesspalace/tusky/components/notifications/NotificationsViewModel.kt

@@ -41,7 +41,7 @@ import com.keylesspalace.tusky.settings.PrefKeys
 import com.keylesspalace.tusky.usecase.TimelineCases
 import com.keylesspalace.tusky.util.StatusDisplayOptions
 import com.keylesspalace.tusky.util.deserialize
-import com.keylesspalace.tusky.util.isLessThan
+import com.keylesspalace.tusky.util.isLessThanOrEqual
 import com.keylesspalace.tusky.util.serialize
 import com.keylesspalace.tusky.util.throttleFirst
 import com.keylesspalace.tusky.util.toViewData
@@ -531,9 +531,7 @@ class NotificationsViewModel @Inject constructor(
                     return@filter if (hasNewestNotificationId(notification.type, status.id, notification.id)) {
                         true
                     } else {
-                        // TODO this now leads sometimes (?) to a "List is empty" being displayed as first item.
-
-                        Log.d(TAG, "Filtering notification "+(n-1)+" for "+status.id+" at "+status.createdAt)
+                        Log.d(TAG, "Filtering notification "+(n-1)+" for "+status.id+"/"+notification.id+" at "+status.createdAt)
                         false
                     }
                 }
@@ -568,7 +566,7 @@ class NotificationsViewModel @Inject constructor(
 
         val highestNotificationId = trackerArray[statusId]
 
-        return if (highestNotificationId == null || highestNotificationId.isLessThan(notificationId)) {
+        return if (highestNotificationId == null || highestNotificationId.isLessThanOrEqual(notificationId)) {
             trackerArray[statusId] = notificationId
 
             true