From e56779dd8d1668177afa199aaa836bea70e68420 Mon Sep 17 00:00:00 2001
From: "Haelwenn (lanodan) Monnier" <contact@hacktivis.me>
Date: Thu, 10 Sep 2020 11:09:11 +0200
Subject: [PATCH] Transmogrifier: Simplify fix_explicit_addressing and
 fix_implicit_addressing

---
 .../web/activity_pub/transmogrifier.ex        | 51 ++++++-------------
 .../web/activity_pub/transmogrifier_test.exs  |  6 +--
 2 files changed, 19 insertions(+), 38 deletions(-)

diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index 4070ed14d..047f23918 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -72,17 +72,21 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     end
   end
 
-  def fix_explicit_addressing(
-        %{"to" => to, "cc" => cc} = object,
-        explicit_mentions,
-        follower_collection
-      ) do
-    explicit_to = Enum.filter(to, fn x -> x in explicit_mentions end)
+  # if directMessage flag is set to true, leave the addressing alone
+  def fix_explicit_addressing(%{"directMessage" => true} = object, _follower_collection),
+    do: object
 
+  def fix_explicit_addressing(%{"to" => to, "cc" => cc} = object, follower_collection) do
+    explicit_mentions =
+      Utils.determine_explicit_mentions(object) ++
+        [Pleroma.Constants.as_public(), follower_collection]
+
+    explicit_to = Enum.filter(to, fn x -> x in explicit_mentions end)
     explicit_cc = Enum.filter(to, fn x -> x not in explicit_mentions end)
 
     final_cc =
       (cc ++ explicit_cc)
+      |> Enum.filter(& &1)
       |> Enum.reject(fn x -> String.ends_with?(x, "/followers") and x != follower_collection end)
       |> Enum.uniq()
 
@@ -91,29 +95,6 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     |> Map.put("cc", final_cc)
   end
 
-  def fix_explicit_addressing(object, _explicit_mentions, _followers_collection), do: object
-
-  # if directMessage flag is set to true, leave the addressing alone
-  def fix_explicit_addressing(%{"directMessage" => true} = object), do: object
-
-  def fix_explicit_addressing(object) do
-    explicit_mentions = Utils.determine_explicit_mentions(object)
-
-    %User{follower_address: follower_collection} =
-      object
-      |> Containment.get_actor()
-      |> User.get_cached_by_ap_id()
-
-    explicit_mentions =
-      explicit_mentions ++
-        [
-          Pleroma.Constants.as_public(),
-          follower_collection
-        ]
-
-    fix_explicit_addressing(object, explicit_mentions, follower_collection)
-  end
-
   # if as:Public is addressed, then make sure the followers collection is also addressed
   # so that the activities will be delivered to local users.
   def fix_implicit_addressing(%{"to" => to, "cc" => cc} = object, followers_collection) do
@@ -137,19 +118,19 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     end
   end
 
-  def fix_implicit_addressing(object, _), do: object
-
   def fix_addressing(object) do
-    {:ok, %User{} = user} = User.get_or_fetch_by_ap_id(object["actor"])
-    followers_collection = User.ap_followers(user)
+    {:ok, %User{follower_address: follower_collection}} =
+      object
+      |> Containment.get_actor()
+      |> User.get_or_fetch_by_ap_id()
 
     object
     |> fix_addressing_list("to")
     |> fix_addressing_list("cc")
     |> fix_addressing_list("bto")
     |> fix_addressing_list("bcc")
-    |> fix_explicit_addressing()
-    |> fix_implicit_addressing(followers_collection)
+    |> fix_explicit_addressing(follower_collection)
+    |> fix_implicit_addressing(follower_collection)
   end
 
   def fix_actor(%{"attributedTo" => actor} = object) do
diff --git a/test/pleroma/web/activity_pub/transmogrifier_test.exs b/test/pleroma/web/activity_pub/transmogrifier_test.exs
index 4c3fcb44a..bb0b58e4d 100644
--- a/test/pleroma/web/activity_pub/transmogrifier_test.exs
+++ b/test/pleroma/web/activity_pub/transmogrifier_test.exs
@@ -446,7 +446,7 @@ defmodule Pleroma.Web.ActivityPub.TransmogrifierTest do
           end)
       }
 
-      fixed_object = Transmogrifier.fix_explicit_addressing(object)
+      fixed_object = Transmogrifier.fix_explicit_addressing(object, user.follower_address)
       assert Enum.all?(explicitly_mentioned_actors, &(&1 in fixed_object["to"]))
       refute "https://social.beepboop.ga/users/dirb" in fixed_object["to"]
       assert "https://social.beepboop.ga/users/dirb" in fixed_object["cc"]
@@ -459,7 +459,7 @@ defmodule Pleroma.Web.ActivityPub.TransmogrifierTest do
         "cc" => []
       }
 
-      fixed_object = Transmogrifier.fix_explicit_addressing(object)
+      fixed_object = Transmogrifier.fix_explicit_addressing(object, user.follower_address)
       assert user.follower_address in fixed_object["to"]
       refute user.follower_address in fixed_object["cc"]
     end
@@ -473,7 +473,7 @@ defmodule Pleroma.Web.ActivityPub.TransmogrifierTest do
         "cc" => [user.follower_address, recipient.follower_address]
       }
 
-      fixed_object = Transmogrifier.fix_explicit_addressing(object)
+      fixed_object = Transmogrifier.fix_explicit_addressing(object, user.follower_address)
 
       assert user.follower_address in fixed_object["cc"]
       refute recipient.follower_address in fixed_object["cc"]