handle duplicates

app/lib/activity_log_audience_helper.rb

@@ -22,6 +22,7 @@ class ActivityLogAudienceHelper
         return ['to', 'bto', 'cc', 'bcc']
           .map { |target| actors(activity_log_event.data[target]) }
           .flatten
+          .uniq
       end
 
       return []

spec/fixtures/activity_log_events/inbound-with-duplicate-recipients.json

@@ -0,0 +1,43 @@
+{
+  "timestamp":"2022-12-08T17:12:38Z",
+  "type": "inbound",
+  "path": "https://example.com/inbox",
+  "data": {
+    "@context": "https://www.w3.org/ns/activitystreams",
+    "actor": "https://other.org/users/bob/",
+    "id": "https://other.org/users/bob/statuses/109473290785654613/activity",
+    "object": {
+      "attributedTo": "https://other.org/users/bob/",
+      "content": "A post to selected audiences",
+      "id": "https://other.org/users/bob/statuses/109473290785654613",
+      "to": [
+        "https://www.w3.org/ns/activitystreams#Public",
+        "https://example.com/users/first-to",
+        "https://example.com/users/first-to",
+        "https://example.com/users/second-to"
+      ],
+      "bto": "https://example.com/users/first-to",
+      "cc": [
+        "https://example.com/users/second-to"
+      ],
+      "bcc": [
+        "https://example.com/users/first-to"
+      ],
+      "type": "Note"
+    },
+    "to": [
+      "https://www.w3.org/ns/activitystreams#Public",
+      "https://example.com/users/first-to",
+      "https://example.com/users/first-to",
+      "https://example.com/users/second-to"
+    ],
+    "bto": "https://example.com/users/first-to",
+    "cc": [
+      "https://example.com/users/second-to"
+    ],
+    "bcc": [
+      "https://example.com/users/first-to"
+    ],
+    "type": "Create"
+  }
+}

spec/lib/activity_log_audience_helper_spec.rb

@@ -73,6 +73,17 @@ RSpec.describe ActivityLogAudienceHelper do
           'second_follower',
         ])
       end
+
+      it 'removes duplicates from audience' do
+        Rails.configuration.x.web_domain = 'example.com'
+        inbound_event = activity_log_event_fixture('inbound-with-duplicate-recipients.json')
+
+        expect(ActivityLogAudienceHelper.audience(inbound_event)).to match_array([
+          'first-to',
+          'second-to'
+        ])
+      end
+
     end
   end
 end