From f3f736afc4b4532ef71d5c6aba42945bd26a7699 Mon Sep 17 00:00:00 2001
From: William Pitcock <nenolod@dereferenced.org>
Date: Thu, 25 Oct 2018 02:47:55 +0000
Subject: [PATCH 1/3] activity: add helper to fetch an activity's parent

---
 lib/pleroma/activity.ex | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/pleroma/activity.ex b/lib/pleroma/activity.ex
index bed96861f..c065f3b6c 100644
--- a/lib/pleroma/activity.ex
+++ b/lib/pleroma/activity.ex
@@ -82,4 +82,10 @@ defmodule Pleroma.Activity do
   def normalize(obj) when is_map(obj), do: Activity.get_by_ap_id(obj["id"])
   def normalize(ap_id) when is_binary(ap_id), do: Activity.get_by_ap_id(ap_id)
   def normalize(_), do: nil
+
+  def get_in_reply_to_activity(%Activity{data: %{"object" => %{"inReplyTo" => ap_id}}}) do
+    get_create_activity_by_object_ap_id(ap_id)
+  end
+
+  def get_in_reply_to_activity(_), do: nil
 end

From fee43ae5e748368022cc5dc6393015ef64e0894b Mon Sep 17 00:00:00 2001
From: William Pitcock <nenolod@dereferenced.org>
Date: Thu, 25 Oct 2018 02:54:29 +0000
Subject: [PATCH 2/3] twitterapi: activity view: implement
 in_reply_to_screen_name using the new graph walking helper

---
 .../twitter_api/representers/activity_representer.ex   | 10 ++++++++++
 lib/pleroma/web/twitter_api/views/activity_view.ex     | 10 ++++++++++
 2 files changed, 20 insertions(+)

diff --git a/lib/pleroma/web/twitter_api/representers/activity_representer.ex b/lib/pleroma/web/twitter_api/representers/activity_representer.ex
index b21bbb205..04857001c 100644
--- a/lib/pleroma/web/twitter_api/representers/activity_representer.ex
+++ b/lib/pleroma/web/twitter_api/representers/activity_representer.ex
@@ -180,6 +180,15 @@ defmodule Pleroma.Web.TwitterAPI.Representers.ActivityRepresenter do
 
     attachments = (object["attachment"] || []) ++ video
 
+    reply_parent = Activity.get_in_reply_to_activity(activity)
+
+    reply_user_nickname =
+      if reply_parent do
+        User.get_cached_by_ap_id(reply_parent.actor).nickname
+      else
+        nil
+      end
+
     %{
       "id" => activity.id,
       "uri" => activity.data["object"]["id"],
@@ -190,6 +199,7 @@ defmodule Pleroma.Web.TwitterAPI.Representers.ActivityRepresenter do
       "is_post_verb" => true,
       "created_at" => created_at,
       "in_reply_to_status_id" => object["inReplyToStatusId"],
+      "in_reply_to_screen_name" => reply_user_nickname,
       "statusnet_conversation_id" => conversation_id,
       "attachments" => attachments |> ObjectRepresenter.enum_to_list(opts),
       "attentions" => attentions,
diff --git a/lib/pleroma/web/twitter_api/views/activity_view.ex b/lib/pleroma/web/twitter_api/views/activity_view.ex
index b9fd062d6..13fb04f95 100644
--- a/lib/pleroma/web/twitter_api/views/activity_view.ex
+++ b/lib/pleroma/web/twitter_api/views/activity_view.ex
@@ -236,6 +236,15 @@ defmodule Pleroma.Web.TwitterAPI.ActivityView do
       HTML.filter_tags(content, User.html_filter_policy(opts[:for]))
       |> Formatter.emojify(object["emoji"])
 
+    reply_parent = Activity.get_in_reply_to_activity(activity)
+
+    reply_user_nickname =
+      if reply_parent do
+        User.get_cached_by_ap_id(reply_parent.actor).nickname
+      else
+        nil
+      end
+
     %{
       "id" => activity.id,
       "uri" => activity.data["object"]["id"],
@@ -246,6 +255,7 @@ defmodule Pleroma.Web.TwitterAPI.ActivityView do
       "is_post_verb" => true,
       "created_at" => created_at,
       "in_reply_to_status_id" => object["inReplyToStatusId"],
+      "in_reply_to_screen_name" => reply_user_nickname,
       "statusnet_conversation_id" => conversation_id,
       "attachments" => (object["attachment"] || []) |> ObjectRepresenter.enum_to_list(opts),
       "attentions" => attentions,

From 9563f3766d45e6c95fe50e371bc0048d9f4a2452 Mon Sep 17 00:00:00 2001
From: William Pitcock <nenolod@dereferenced.org>
Date: Thu, 25 Oct 2018 03:03:44 +0000
Subject: [PATCH 3/3] tests: update for new in_reply_to_screen_name field

---
 test/web/twitter_api/representers/activity_representer_test.exs | 1 +
 test/web/twitter_api/views/activity_view_test.exs               | 1 +
 2 files changed, 2 insertions(+)

diff --git a/test/web/twitter_api/representers/activity_representer_test.exs b/test/web/twitter_api/representers/activity_representer_test.exs
index 894d20049..ae6f62ed0 100644
--- a/test/web/twitter_api/representers/activity_representer_test.exs
+++ b/test/web/twitter_api/representers/activity_representer_test.exs
@@ -139,6 +139,7 @@ defmodule Pleroma.Web.TwitterAPI.Representers.ActivityRepresenterTest do
       "is_post_verb" => true,
       "created_at" => "Tue May 24 13:26:08 +0000 2016",
       "in_reply_to_status_id" => 213_123,
+      "in_reply_to_screen_name" => nil,
       "statusnet_conversation_id" => convo_object.id,
       "attachments" => [
         ObjectRepresenter.to_map(object)
diff --git a/test/web/twitter_api/views/activity_view_test.exs b/test/web/twitter_api/views/activity_view_test.exs
index b9a8efdad..3ab87d6fa 100644
--- a/test/web/twitter_api/views/activity_view_test.exs
+++ b/test/web/twitter_api/views/activity_view_test.exs
@@ -36,6 +36,7 @@ defmodule Pleroma.Web.TwitterAPI.ActivityViewTest do
       "favorited" => false,
       "id" => activity.id,
       "in_reply_to_status_id" => nil,
+      "in_reply_to_screen_name" => nil,
       "is_local" => true,
       "is_post_verb" => true,
       "possibly_sensitive" => false,