Conversations: Return last dm for conversation, not last message.

lib/pleroma/conversation/participation.ex

@@ -162,10 +162,13 @@ def for_user_with_last_activity_id(user, params \\ %{}) do
     for_user(user, params)
     |> Enum.map(fn participation ->
       activity_id =
-        ActivityPub.fetch_latest_activity_id_for_context(participation.conversation.ap_id, %{
-          user: user,
-          blocking_user: user
-        })
+        ActivityPub.fetch_latest_direct_activity_id_for_context(
+          participation.conversation.ap_id,
+          %{
+            user: user,
+            blocking_user: user
+          }
+        )
 
       %{
         participation

lib/pleroma/web/activity_pub/activity_pub.ex

@@ -210,7 +210,7 @@ def stream_out_participations(%Object{data: %{"context" => context}}, user) do
       conversation = Repo.preload(conversation, :participations)
 
       last_activity_id =
-        fetch_latest_activity_id_for_context(conversation.ap_id, %{
+        fetch_latest_direct_activity_id_for_context(conversation.ap_id, %{
           user: user,
           blocking_user: user
         })
@@ -517,11 +517,12 @@ def fetch_activities_for_context(context, opts \\ %{}) do
     |> Repo.all()
   end
 
-  @spec fetch_latest_activity_id_for_context(String.t(), keyword() | map()) ::
+  @spec fetch_latest_direct_activity_id_for_context(String.t(), keyword() | map()) ::
           FlakeId.Ecto.CompatType.t() | nil
-  def fetch_latest_activity_id_for_context(context, opts \\ %{}) do
+  def fetch_latest_direct_activity_id_for_context(context, opts \\ %{}) do
     context
     |> fetch_activities_for_context_query(Map.merge(%{skip_preload: true}, opts))
+    |> restrict_visibility(%{visibility: "direct"})
     |> limit(1)
     |> select([a], a.id)
     |> Repo.one()

lib/pleroma/web/mastodon_api/views/conversation_view.ex

@@ -23,10 +23,13 @@ def render("participation.json", %{participation: participation, for: user}) do
 
     last_activity_id =
       with nil <- participation.last_activity_id do
-        ActivityPub.fetch_latest_activity_id_for_context(participation.conversation.ap_id, %{
-          user: user,
-          blocking_user: user
-        })
+        ActivityPub.fetch_latest_direct_activity_id_for_context(
+          participation.conversation.ap_id,
+          %{
+            user: user,
+            blocking_user: user
+          }
+        )
       end
 
     activity = Activity.get_by_id_with_object(last_activity_id)

test/web/mastodon_api/views/conversation_view_test.exs

@@ -15,8 +15,17 @@ test "represents a Mastodon Conversation entity" do
     user = insert(:user)
     other_user = insert(:user)
 
+    {:ok, parent} = CommonAPI.post(user, %{status: "parent"})
+
     {:ok, activity} =
-      CommonAPI.post(user, %{status: "hey @#{other_user.nickname}", visibility: "direct"})
+      CommonAPI.post(user, %{
+        status: "hey @#{other_user.nickname}",
+        visibility: "direct",
+        in_reply_to_id: parent.id
+      })
+
+    {:ok, _reply_activity} =
+      CommonAPI.post(user, %{status: "hu", visibility: "public", in_reply_to_id: parent.id})
 
     [participation] = Participation.for_user_with_last_activity_id(user)