add tests

test/feed_reader/rss_test.exs

@@ -0,0 +1,38 @@
+defmodule FeedReader.RSSTest do
+  use ExUnit.Case, async: true
+
+  alias FeedReader.Formats.RSS
+
+  @xml ~s(<rss version="2.0"><channel><title>Example</title><description>Latest news</description><link>https://example.com/</link><category>News</category><category>News</category><item><title>Story</title><guid isPermaLink="false">story-1</guid><link>/story</link><author>Writer</author><description>Summary</description><content:encoded><![CDATA[<p>Full text</p>]]></content:encoded><pubDate>Mon, 24 Feb 2025 17:00:05 GMT</pubDate></item><item><title> </title><link>https://example.com/second</link><pubDate>not a date</pubDate></item><item><title> </title></item></channel></rss>)
+
+  test "format callback normalizes feed metadata and RSS items" do
+    sink = fn event -> send(self(), event) end
+    assert {:ok, _} = parse(@xml, sink)
+    assert_receive {:feed, %FeedReader.Feed{title: "Example", categories: ["News"]}}
+    assert_receive {:item, %FeedReader.Item{title: "Story", uuid: "story-1"}}
+    assert {:ok, _} = parse("<rss version='2.0'><channel/></rss>", sink)
+  end
+
+  test "stops malformed and over-budget input and rejects orphan SAX events" do
+    sink = fn _event -> :ok end
+    assert {:error, _} = parse("<rss version='2.0'>", sink)
+
+    assert {:ok, %{error: {:resource_limit, :max_item_bytes, 1}}} =
+             parse(@xml, sink, max_item_bytes: 1)
+
+    for {opts, events, error} <- [
+          {[max_xml_events: 0], [start_document: [], characters: "x", end_element: "item"],
+           {:resource_limit, :max_xml_events, 0}},
+          {[], [characters: "x", end_element: "item"], :invalid_sax_event}
+        ] do
+      state = RSS.new_parser_state(sink, opts)
+
+      for {event, data} <- events do
+        assert {:stop, %{error: ^error}} = RSS.handler().handle_event(event, data, state)
+      end
+    end
+  end
+
+  defp parse(xml, sink, opts \\ []),
+    do: Saxy.parse_string(xml, RSS.handler(), RSS.new_parser_state(sink, opts))
+end