From f4463d4adf9de594d743c69ac5c7cb8eec20c9d0 Mon Sep 17 00:00:00 2001
From: FloatingGhost <hannah@coffee-and-dreams.uk>
Date: Sun, 4 Dec 2022 15:27:48 +0000
Subject: [PATCH] Include followed hashtags in home timeline

---
 lib/mix/tasks/pleroma/user.ex                  |  7 +++++++
 lib/pleroma/web/activity_pub/activity_pub.ex   | 12 ++++++++++--
 .../controllers/timeline_controller.ex         |  2 +-
 .../web/activity_pub/activity_pub_test.exs     | 18 ++++++++++++++++++
 4 files changed, 36 insertions(+), 3 deletions(-)

diff --git a/lib/mix/tasks/pleroma/user.ex b/lib/mix/tasks/pleroma/user.ex
index 278a01acc..dd1cdca5b 100644
--- a/lib/mix/tasks/pleroma/user.ex
+++ b/lib/mix/tasks/pleroma/user.ex
@@ -471,9 +471,15 @@ defmodule Mix.Tasks.Pleroma.User do
 
   def run(["timeline_query", nickname]) do
     start_pleroma()
+
     params = %{local: true}
 
     with %User{local: true} = user <- User.get_cached_by_nickname(nickname) do
+      followed_hashtags =
+        user
+        |> User.followed_hashtags()
+        |> Enum.map(& &1.id)
+
       params =
         params
         |> Map.put(:type, ["Create", "Announce"])
@@ -484,6 +490,7 @@ defmodule Mix.Tasks.Pleroma.User do
         |> Map.put(:announce_filtering_user, user)
         |> Map.put(:user, user)
         |> Map.put(:local_only, params[:local])
+        |> Map.put(:hashtags, followed_hashtags)
         |> Map.delete(:local)
 
       _activities =
diff --git a/lib/pleroma/web/activity_pub/activity_pub.ex b/lib/pleroma/web/activity_pub/activity_pub.ex
index a8a3188b7..8233bcbf8 100644
--- a/lib/pleroma/web/activity_pub/activity_pub.ex
+++ b/lib/pleroma/web/activity_pub/activity_pub.ex
@@ -933,11 +933,19 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
     )
   end
 
+  # Essentially, either look for activities addressed to `recipients`, _OR_ ones
+  # that reference a hashtag that the user follows
+  # Firstly, two fallbacks in case there's no hashtag constraint, or the user doesn't
+  # follow any
   defp restrict_recipients_or_hashtags(query, recipients, user, nil) do
     restrict_recipients(query, recipients, user)
   end
 
-  defp restrict_recipients_or_hashtags(query, recipients, user, hashtag_ids) do
+  defp restrict_recipients_or_hashtags(query, recipients, user, []) do
+    restrict_recipients(query, recipients, user)
+  end
+
+  defp restrict_recipients_or_hashtags(query, recipients, _user, hashtag_ids) do
     from(
       [activity, object] in query,
       join: hto in "hashtags_objects",
@@ -1395,7 +1403,7 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
       |> maybe_preload_report_notes(opts)
       |> maybe_set_thread_muted_field(opts)
       |> maybe_order(opts)
-      |> restrict_recipients_or_hashtags(recipients, opts[:user], opts[:hashtags])
+      |> restrict_recipients_or_hashtags(recipients, opts[:user], opts[:followed_hashtags])
       |> restrict_replies(opts)
       |> restrict_since(opts)
       |> restrict_local(opts)
diff --git a/lib/pleroma/web/mastodon_api/controllers/timeline_controller.ex b/lib/pleroma/web/mastodon_api/controllers/timeline_controller.ex
index b82bb498a..2d0e36420 100644
--- a/lib/pleroma/web/mastodon_api/controllers/timeline_controller.ex
+++ b/lib/pleroma/web/mastodon_api/controllers/timeline_controller.ex
@@ -55,7 +55,7 @@ defmodule Pleroma.Web.MastodonAPI.TimelineController do
       |> Map.put(:announce_filtering_user, user)
       |> Map.put(:user, user)
       |> Map.put(:local_only, params[:local])
-      |> Map.put(:hashtags, followed_hashtags)
+      |> Map.put(:followed_hashtags, followed_hashtags)
       |> Map.delete(:local)
 
     activities =
diff --git a/test/pleroma/web/activity_pub/activity_pub_test.exs b/test/pleroma/web/activity_pub/activity_pub_test.exs
index 8d39b1076..fc452ef1a 100644
--- a/test/pleroma/web/activity_pub/activity_pub_test.exs
+++ b/test/pleroma/web/activity_pub/activity_pub_test.exs
@@ -719,6 +719,24 @@ defmodule Pleroma.Web.ActivityPub.ActivityPubTest do
     end
   end
 
+  describe "fetch activities for followed hashtags" do
+    test "it should return public activities that reference a given hashtag" do
+      hashtag = insert(:hashtag, name: "tenshi")
+      user = insert(:user)
+
+      {:ok, public} = CommonAPI.post(user, %{status: "maji #tenshi", visibility: "public"})
+      {:ok, _unrelated} = CommonAPI.post(user, %{status: "dai #tensh", visibility: "public"})
+      {:ok, unlisted} = CommonAPI.post(user, %{status: "maji #tenshi", visibility: "unlisted"})
+      {:ok, _private} = CommonAPI.post(user, %{status: "maji #tenshi", visibility: "private"})
+
+      activities = ActivityPub.fetch_activities([], %{followed_hashtags: [hashtag.id]})
+      assert length(activities) == 2
+      public_id = public.id
+      unlisted_id = unlisted.id
+      assert [%{id: ^public_id}, %{id: ^unlisted_id}] = activities
+    end
+  end
+
   describe "fetch activities in context" do
     test "retrieves activities that have a given context" do
       {:ok, activity} = ActivityBuilder.insert(%{"type" => "Create", "context" => "2hu"})