From fb654acfadfeec00a1a52e2af96e922dc4b88b01 Mon Sep 17 00:00:00 2001
From: Mark Felder <feld@feld.me>
Date: Sat, 20 Jul 2024 23:48:54 -0400
Subject: [PATCH] Fix OpenGraph and Twitter metadata providers when parsing
 objects with no content or summary fields.

---
 changelog.d/metadata-provider-empty-post.fix |  1 +
 lib/pleroma/web/metadata/utils.ex            |  5 +++-
 test/pleroma/web/metadata/utils_test.exs     | 28 +++++++++++++++-----
 3 files changed, 27 insertions(+), 7 deletions(-)
 create mode 100644 changelog.d/metadata-provider-empty-post.fix

diff --git a/changelog.d/metadata-provider-empty-post.fix b/changelog.d/metadata-provider-empty-post.fix
new file mode 100644
index 000000000..8d6341c6c
--- /dev/null
+++ b/changelog.d/metadata-provider-empty-post.fix
@@ -0,0 +1 @@
+Fix OpenGraph and Twitter metadata providers when parsing objects with no content or summary fields.
diff --git a/lib/pleroma/web/metadata/utils.ex b/lib/pleroma/web/metadata/utils.ex
index 80a8be9a2..8f61ace24 100644
--- a/lib/pleroma/web/metadata/utils.ex
+++ b/lib/pleroma/web/metadata/utils.ex
@@ -25,11 +25,14 @@ def scrub_html_and_truncate(%{data: %{"summary" => summary}} = object)
     |> scrub_html_and_truncate_object_field(object)
   end
 
-  def scrub_html_and_truncate(%{data: %{"content" => content}} = object) do
+  def scrub_html_and_truncate(%{data: %{"content" => content}} = object)
+      when is_binary(content) and content != "" do
     content
     |> scrub_html_and_truncate_object_field(object)
   end
 
+  def scrub_html_and_truncate(%{}), do: ""
+
   def scrub_html_and_truncate(content, max_length \\ 200, omission \\ "...")
       when is_binary(content) do
     content
diff --git a/test/pleroma/web/metadata/utils_test.exs b/test/pleroma/web/metadata/utils_test.exs
index 3daf852fb..9bc02dadf 100644
--- a/test/pleroma/web/metadata/utils_test.exs
+++ b/test/pleroma/web/metadata/utils_test.exs
@@ -8,7 +8,7 @@ defmodule Pleroma.Web.Metadata.UtilsTest do
   alias Pleroma.Web.Metadata.Utils
 
   describe "scrub_html_and_truncate/1" do
-    test "it returns content text without encode HTML if summary is nil" do
+    test "it returns content text without HTML if summary is nil" do
       user = insert(:user)
 
       note =
@@ -17,14 +17,14 @@ test "it returns content text without encode HTML if summary is nil" do
             "actor" => user.ap_id,
             "id" => "https://pleroma.gov/objects/whatever",
             "summary" => nil,
-            "content" => "Pleroma's really cool!"
+            "content" => "Pleroma's really cool!<br>"
           }
         })
 
       assert Utils.scrub_html_and_truncate(note) == "Pleroma's really cool!"
     end
 
-    test "it returns context text without encode HTML if summary is empty" do
+    test "it returns content text without HTML if summary is empty" do
       user = insert(:user)
 
       note =
@@ -33,14 +33,14 @@ test "it returns context text without encode HTML if summary is empty" do
             "actor" => user.ap_id,
             "id" => "https://pleroma.gov/objects/whatever",
             "summary" => "",
-            "content" => "Pleroma's really cool!"
+            "content" => "Pleroma's really cool!<br>"
           }
         })
 
       assert Utils.scrub_html_and_truncate(note) == "Pleroma's really cool!"
     end
 
-    test "it returns summary text without encode HTML if summary is filled" do
+    test "it returns summary text without HTML if summary is filled" do
       user = insert(:user)
 
       note =
@@ -48,7 +48,7 @@ test "it returns summary text without encode HTML if summary is filled" do
           data: %{
             "actor" => user.ap_id,
             "id" => "https://pleroma.gov/objects/whatever",
-            "summary" => "Public service announcement on caffeine consumption",
+            "summary" => "Public service announcement on caffeine consumption<br>",
             "content" => "cofe"
           }
         })
@@ -57,6 +57,22 @@ test "it returns summary text without encode HTML if summary is filled" do
                "Public service announcement on caffeine consumption"
     end
 
+    test "it returns empty string if summary and content are absent" do
+      user = insert(:user)
+
+      note =
+        insert(:note, %{
+          data: %{
+            "actor" => user.ap_id,
+            "id" => "https://pleroma.gov/objects/whatever",
+            "content" => nil,
+            "summary" => nil
+          }
+        })
+
+      assert Utils.scrub_html_and_truncate(note) == ""
+    end
+
     test "it does not return old content after editing" do
       user = insert(:user)