removes duplicates from relay subscription list

lib/mix/tasks/pleroma/relay.ex

@@ -53,13 +53,11 @@ def run(["unfollow", target]) do
   def run(["list"]) do
     start_pleroma()
 
-    with %User{} = user <- Relay.get_actor() do
-      user.following
-      |> Enum.each(fn entry ->
-        URI.parse(entry)
-        |> Map.get(:host)
-        |> shell_info()
-      end)
+    with %User{following: following} = _user <- Relay.get_actor() do
+      following
+      |> Enum.map(fn entry -> URI.parse(entry).host end)
+      |> Enum.uniq()
+      |> Enum.each(&shell_info(&1))
     else
       e -> shell_error("Error while fetching relay subscription list: #{inspect(e)}")
     end

test/tasks/relay_test.exs

@@ -69,4 +69,27 @@ test "relay is unfollowed" do
       assert undo_activity.data["object"] == cancelled_activity.data
     end
   end
+
+  describe "mix pleroma.relay list" do
+    test "Prints relay subscription list" do
+      :ok = Mix.Tasks.Pleroma.Relay.run(["list"])
+
+      refute_receive {:mix_shell, :info, _}
+
+      Pleroma.Web.ActivityPub.Relay.get_actor()
+      |> Ecto.Changeset.change(
+        following: [
+          "http://test-app.com/user/test1",
+          "http://test-app.com/user/test1",
+          "http://test-app-42.com/user/test1"
+        ]
+      )
+      |> Pleroma.User.update_and_set_cache()
+
+      :ok = Mix.Tasks.Pleroma.Relay.run(["list"])
+
+      assert_receive {:mix_shell, :info, ["test-app.com"]}
+      assert_receive {:mix_shell, :info, ["test-app-42.com"]}
+    end
+  end
 end