Fix failing tests

lib/pleroma/activity.ex

@@ -108,17 +108,20 @@ defmodule Pleroma.Activity do
     %{
       id: data["id"],
       context: data["context"],
-      type: "tombstone",
+      type: "Tombstone",
       published: data["published"],
       deleted: deleted
     }
   end
 
   def swap_data_with_tombstone(activity) do
-    tombstone = get_tombstone(activity)
-
-    activity
-    |> change(%{data: tombstone})
-    |> Repo.update()
+    with tombstone = get_tombstone(activity),
+         Notification.clear(activity),
+         {:ok, changed_activity} =
+           activity
+           |> change(%{data: tombstone})
+           |> Repo.update() do
+      {:ok, changed_activity}
+    end
   end
 end

lib/pleroma/notification.ex

@@ -75,10 +75,14 @@ defmodule Pleroma.Notification do
     end
   end
 
-  def clear(user) do
-    query = from(n in Notification, where: n.user_id == ^user.id)
+  def clear(%User{} = user) do
+    from(n in Notification, where: n.user_id == ^user.id)
+    |> Repo.delete_all()
+  end
 
-    Repo.delete_all(query)
+  def clear(%Activity{} = activity) do
+    from(n in Notification, where: n.activity_id == ^activity.id)
+    |> Repo.delete_all()
   end
 
   def dismiss(%{id: user_id} = _user, id) do

lib/pleroma/web/activity_pub/transmogrifier.ex

@@ -586,7 +586,8 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   end
 
   def set_reply_to_uri(%{"inReplyTo" => inReplyTo} = object) do
-    with false <- String.starts_with?(inReplyTo, "http"),
+    with false <- is_nil(inReplyTo),
+         false <- String.starts_with?(inReplyTo, "http"),
          {:ok, %{data: replied_to_object}} <- get_obj_helper(inReplyTo) do
       Map.put(object, "inReplyTo", replied_to_object["external_url"] || inReplyTo)
     else