Use same context for quote posts as the post that's being quoted (#379)

See AkkomaGang/akkoma#350 (comment)

When making quotes through Mast-API, they will now have the same context as the quoted post. This also results in them being showed when fetching the thread. I checked Misskey to see how it's there, and they show the quotes there as well, see e.g. <https://mk.toast.cafe/notes/98u1g0tulg>.

An example from Akkoma:

Co-authored-by: ilja <git@ilja.space>
Reviewed-on: AkkomaGang/akkoma#379
Reviewed-by: floatingghost <hannah@coffee-and-dreams.uk>
Co-authored-by: ilja <akkoma.dev@ilja.space>
Co-committed-by: ilja <akkoma.dev@ilja.space>

CHANGELOG.md

@@ -25,6 +25,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Non-admin users now cannot register `admin` scope tokens (not security-critical, they didn't work before, but you _could_ create them)
   - Admin scopes will be dropped on create
 - Rich media will now backoff for 20 minutes after a failure
+- Quote posts are now considered as part of the same thread as the post they are quoting
 - Simplified HTTP signature processing
 - Rich media will now hard-exit after 5 seconds, to prevent timeline hangs
 

lib/pleroma/web/common_api/activity_draft.ex

@@ -177,7 +177,7 @@ defp to_and_cc(draft) do
   end
 
   defp context(draft) do
-    context = Utils.make_context(draft.in_reply_to, draft.in_reply_to_conversation)
+    context = Utils.make_context(draft)
     %__MODULE__{draft | context: context}
   end
 

lib/pleroma/web/common_api/utils.ex

@@ -230,12 +230,13 @@ def get_content_type(content_type) do
     end
   end
 
-  def make_context(_, %Participation{} = participation) do
+  def make_context(%{in_reply_to_conversation: %Participation{} = participation}) do
     Repo.preload(participation, :conversation).conversation.ap_id
   end
 
-  def make_context(%Activity{data: %{"context" => context}}, _), do: context
+  def make_context(%{in_reply_to: %Activity{data: %{"context" => context}}}), do: context
-  def make_context(_, _), do: Utils.generate_context_id()
+  def make_context(%{quote: %Activity{data: %{"context" => context}}}), do: context
+  def make_context(_), do: Utils.generate_context_id()
 
   def maybe_add_attachments(parsed, _attachments, false = _no_links), do: parsed
 

test/pleroma/web/mastodon_api/controllers/status_controller_test.exs

@@ -2023,6 +2023,7 @@ test "posting a quote", %{conn: conn} do
       assert response["quote_id"] == quoted_status.id
       assert response["quote"]["id"] == quoted_status.id
       assert response["quote"]["content"] == quoted_status.object.data["content"]
+      assert response["pleroma"]["context"] == quoted_status.data["context"]
     end
 
     test "posting a quote, quoting a status that isn't public", %{conn: conn} do