Create mentions only for explicitly mentioned users

lib/pleroma/web/mastodon_api/views/status_view.ex

@@ -149,8 +149,14 @@ def render("status.json", %{activity: %{data: %{"object" => _object}} = activity
     tags = object.data["tag"] || []
     sensitive = object.data["sensitive"] || Enum.member?(tags, "nsfw")
 
+    tag_mentions =
+      tags
+      |> Enum.filter(fn tag -> is_map(tag) and tag["type"] == "Mention" end)
+      |> Enum.map(fn tag -> tag["href"] end)
+
     mentions =
-      activity.recipients
+      (object.data["to"] ++ tag_mentions)
+      |> Enum.uniq()
       |> Enum.map(fn ap_id -> User.get_cached_by_ap_id(ap_id) end)
       |> Enum.filter(& &1)
       |> Enum.map(fn user -> AccountView.render("mention.json", %{user: user}) end)

test/support/factory.ex

@@ -117,6 +117,7 @@ def direct_note_activity_factory do
   def note_activity_factory(attrs \\ %{}) do
     user = attrs[:user] || insert(:user)
     note = attrs[:note] || insert(:note, user: user)
+    attrs = Map.drop(attrs, [:user, :note])
 
     data = %{
       "id" => Pleroma.Web.ActivityPub.Utils.generate_activity_id(),
@@ -133,6 +134,7 @@ def note_activity_factory(attrs \\ %{}) do
       actor: data["actor"],
       recipients: data["to"]
     }
+    |> Map.merge(attrs)
   end
 
   def article_activity_factory do

test/web/admin_api/admin_api_controller_test.exs

@@ -1234,7 +1234,6 @@ test "returns created dm", %{conn: conn} do
 
       recipients = Enum.map(response["mentions"], & &1["username"])
 
-      assert conn.assigns[:user].nickname in recipients
       assert reporter.nickname in recipients
       assert response["content"] == "I will check it out"
       assert response["visibility"] == "direct"

test/web/mastodon_api/status_view_test.exs

@@ -203,10 +203,71 @@ test "contains mentions" do
 
     status = StatusView.render("status.json", %{activity: activity})
 
-    actor = User.get_cached_by_ap_id(activity.actor)
-
     assert status.mentions ==
-             Enum.map([user, actor], fn u -> AccountView.render("mention.json", %{user: u}) end)
+             Enum.map([user], fn u -> AccountView.render("mention.json", %{user: u}) end)
+  end
+
+  test "create mentions from the 'to' field" do
+    %User{ap_id: recipient_ap_id} = insert(:user)
+    cc = insert_pair(:user) |> Enum.map(& &1.ap_id)
+
+    object =
+      insert(:note, %{
+        data: %{
+          "to" => [recipient_ap_id],
+          "cc" => cc
+        }
+      })
+
+    activity =
+      insert(:note_activity, %{
+        note: object,
+        recipients: [recipient_ap_id | cc]
+      })
+
+    assert length(activity.recipients) == 3
+
+    %{mentions: [mention] = mentions} = StatusView.render("status.json", %{activity: activity})
+
+    assert length(mentions) == 1
+    assert mention.url == recipient_ap_id
+  end
+
+  test "create mentions from the 'tag' field" do
+    recipient = insert(:user)
+    cc = insert_pair(:user) |> Enum.map(& &1.ap_id)
+
+    object =
+      insert(:note, %{
+        data: %{
+          "cc" => cc,
+          "tag" => [
+            %{
+              "href" => recipient.ap_id,
+              "name" => recipient.nickname,
+              "type" => "Mention"
+            },
+            %{
+              "href" => "https://example.com/search?tag=test",
+              "name" => "#test",
+              "type" => "Hashtag"
+            }
+          ]
+        }
+      })
+
+    activity =
+      insert(:note_activity, %{
+        note: object,
+        recipients: [recipient.ap_id | cc]
+      })
+
+    assert length(activity.recipients) == 3
+
+    %{mentions: [mention] = mentions} = StatusView.render("status.json", %{activity: activity})
+
+    assert length(mentions) == 1
+    assert mention.url == recipient.ap_id
   end
 
   test "attachments" do