Fix edge cases

lib/pleroma/constants.ex

@@ -43,6 +43,18 @@ defmodule Pleroma.Constants do
     ]
   )
 
+  const(status_object_types,
+    do: [
+      "Note",
+      "Question",
+      "Audio",
+      "Video",
+      "Event",
+      "Article",
+      "Page"
+    ]
+  )
+
   const(updatable_object_types,
     do: [
       "Note",

lib/pleroma/web/activity_pub/mrf/emoji_policy.ex

@@ -31,8 +31,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.EmojiPolicy do
   def history_awareness, do: :manual
 
   @impl Pleroma.Web.ActivityPub.MRF.Policy
-  def filter(%{"type" => type, "object" => %{} = object} = message)
-      when type in ["Create", "Update"] do
+  def filter(%{"type" => type, "object" => %{"type" => objtype} = object} = message)
+      when type in ["Create", "Update"] and objtype in Pleroma.Constants.status_object_types() do
     with {:ok, object} <-
            Updater.do_with_history(object, fn object ->
              {:ok, process_remove(object, :url, config_remove_url())}
@@ -102,46 +102,51 @@ defmodule Pleroma.Web.ActivityPub.MRF.EmojiPolicy do
   end
 
   defp process_remove_impl(object, extract_from_tag, extract_from_emoji, patterns) do
-    processed_tag =
-      Enum.filter(
-        object["tag"],
-        fn
-          %{"type" => "Emoji"} = tag ->
-            str = extract_from_tag.(tag)
+    object =
+      if object["tag"] do
+        Map.put(
+          object,
+          "tag",
+          Enum.filter(
+            object["tag"],
+            fn
+              %{"type" => "Emoji"} = tag ->
+                str = extract_from_tag.(tag)
 
-            if is_binary(str) do
-              not match_any?(str, patterns)
-            else
-              true
+                if is_binary(str) do
+                  not match_any?(str, patterns)
+                else
+                  true
+                end
+
+              _ ->
+                true
             end
-
-          _ ->
-            true
-        end
-      )
-
-    processed_emoji =
-      if object["emoji"] do
-        object["emoji"]
-        |> Enum.reduce(%{}, fn {name, url} = emoji, acc ->
-          if not match_any?(extract_from_emoji.(emoji), patterns) do
-            Map.put(acc, name, url)
-          else
-            acc
-          end
-        end)
+          )
+        )
       else
-        nil
+        object
       end
 
-    if processed_emoji do
-      object
-      |> Map.put("tag", processed_tag)
-      |> Map.put("emoji", processed_emoji)
-    else
-      object
-      |> Map.put("tag", processed_tag)
-    end
+    object =
+      if object["emoji"] do
+        Map.put(
+          object,
+          "emoji",
+          object["emoji"]
+          |> Enum.reduce(%{}, fn {name, url} = emoji, acc ->
+            if not match_any?(extract_from_emoji.(emoji), patterns) do
+              Map.put(acc, name, url)
+            else
+              acc
+            end
+          end)
+        )
+      else
+        object
+      end
+
+    object
   end
 
   defp matched_emoji_checker(urls, shortcodes) do

test/pleroma/web/activity_pub/mrf/emoji_policy_test.exs

@@ -389,4 +389,37 @@ defmodule Pleroma.Web.ActivityPub.MRF.EmojiPolicyTest do
              } = filtered
     end
   end
+
+  describe "edge cases" do
+    setup do
+      clear_config([:mrf_emoji, :remove_url], [
+        "https://example.org/test.png",
+        ~r{/biribiri/mikoto_smile[23]\.png},
+        "nekomimi_girl_emoji"
+      ])
+
+      :ok
+    end
+
+    test "non-statuses" do
+      answer = @status_data |> put_in(["object", "type"], "Answer")
+      {:ok, filtered} = MRF.filter_one(EmojiPolicy, answer)
+
+      assert filtered == answer
+    end
+
+    test "without tag" do
+      status = @status_data |> Map.put("object", Map.drop(@status_data["object"], ["tag"]))
+      {:ok, filtered} = MRF.filter_one(EmojiPolicy, status)
+
+      refute Map.has_key?(filtered["object"], "tag")
+    end
+
+    test "without emoji" do
+      status = @status_data |> Map.put("object", Map.drop(@status_data["object"], ["emoji"]))
+      {:ok, filtered} = MRF.filter_one(EmojiPolicy, status)
+
+      refute Map.has_key?(filtered["object"], "emoji")
+    end
+  end
 end