Merge branch '2257-self-chat' into 'develop'

Resolve "Can't message yourself in a chat (but can start it)"

Closes #2257

See merge request pleroma/pleroma!3099

test/pleroma/web/common_api_test.exs

@@ -95,6 +95,20 @@ defmodule Pleroma.Web.CommonAPITest do
   describe "posting chat messages" do
     setup do: clear_config([:instance, :chat_limit])
 
+    test "it posts a self-chat" do
+      author = insert(:user)
+      recipient = author
+
+      {:ok, activity} =
+        CommonAPI.post_chat_message(
+          author,
+          recipient,
+          "remember to buy milk when milk truk arive"
+        )
+
+      assert activity.data["type"] == "Create"
+    end
+
     test "it posts a chat message without content but with an attachment" do
       author = insert(:user)
       recipient = insert(:user)