From 0de1a7629c5dbf3f6fba69a41bbeff5947558899 Mon Sep 17 00:00:00 2001
From: "Haelwenn (lanodan) Monnier" <contact@hacktivis.me>
Date: Thu, 25 Jan 2024 00:26:55 +0100
Subject: [PATCH] Maps: Add filter_empty_values/1

---
 lib/pleroma/maps.ex        | 15 ++++++++++++++-
 test/pleroma/maps_test.exs | 22 ++++++++++++++++++++++
 2 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 test/pleroma/maps_test.exs

diff --git a/lib/pleroma/maps.ex b/lib/pleroma/maps.ex
index 6d586e53e..5020a8ff8 100644
--- a/lib/pleroma/maps.ex
+++ b/lib/pleroma/maps.ex
@@ -1,5 +1,5 @@
 # Pleroma: A lightweight social networking server
-# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
+# Copyright © 2017-2024 Pleroma Authors <https://pleroma.social/>
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Maps do
@@ -18,4 +18,17 @@ defmodule Pleroma.Maps do
   rescue
     _ -> data
   end
+
+  def filter_empty_values(data) do
+    # TODO: Change to Map.filter in Elixir 1.13+
+    data
+    |> Enum.filter(fn
+      {_k, nil} -> false
+      {_k, ""} -> false
+      {_k, []} -> false
+      {_k, %{} = v} -> Map.keys(v) != []
+      {_k, _v} -> true
+    end)
+    |> Map.new()
+  end
 end
diff --git a/test/pleroma/maps_test.exs b/test/pleroma/maps_test.exs
new file mode 100644
index 000000000..05f1b18b2
--- /dev/null
+++ b/test/pleroma/maps_test.exs
@@ -0,0 +1,22 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2024 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.MapsTest do
+  use Pleroma.DataCase, async: true
+
+  alias Pleroma.Maps
+
+  describe "filter_empty_values/1" do
+    assert %{"bar" => "b", "ray" => ["foo"], "objs" => %{"a" => "b"}} ==
+             Maps.filter_empty_values(%{
+               "foo" => nil,
+               "fooz" => "",
+               "bar" => "b",
+               "rei" => [],
+               "ray" => ["foo"],
+               "obj" => %{},
+               "objs" => %{"a" => "b"}
+             })
+  end
+end