add `mix pleroma.user delete_activities NICKNAME` task

lib/mix/tasks/pleroma/user.ex

@@ -304,6 +304,18 @@ def run(["invite"]) do
     end
   end
 
+  def run(["delete_activities", nickname]) do
+    Common.start_pleroma()
+
+    with %User{local: true} = user <- User.get_by_nickname(nickname) do
+      User.delete_user_activities(user)
+      Mix.shell().info("User #{nickname} deleted.")
+    else
+      _ ->
+        Mix.shell().error("No local user #{nickname}")
+    end
+  end
+
   defp set_moderator(user, value) do
     info_cng = User.Info.admin_api_update(user.info, %{is_moderator: value})
 

lib/pleroma/user.ex

@@ -1083,6 +1083,12 @@ def delete(%User{} = user) do
     friends
     |> Enum.each(fn followed -> User.unfollow(user, followed) end)
 
+    delete_user_activities(user)
+
+    {:ok, user}
+  end
+
+  def delete_user_activities(user) do
     query = from(a in Activity, where: a.actor == ^user.ap_id)
 
     Repo.all(query)
@@ -1096,8 +1102,6 @@ def delete(%User{} = user) do
           "Doing nothing"
       end
     end)
-
-    {:ok, user}
   end
 
   def html_filter_policy(%User{info: %{no_rich_text: true}}) do