Fix getting Create and Update out of order (#36176)

app/lib/activitypub/activity/update.rb

@@ -28,6 +28,9 @@ class ActivityPub::Activity::Update < ActivityPub::Activity
 
     @status = Status.find_by(uri: object_uri, account_id: @account.id)
 
+    # We may be getting `Create` and `Update` out of order
+    @status ||= ActivityPub::Activity::Create.new(@json, @account, **@options).perform
+
     return if @status.nil?
 
     ActivityPub::ProcessStatusUpdateService.new.call(@status, @json, @object, request_id: @options[:request_id])

spec/lib/activitypub/activity_spec.rb

@@ -0,0 +1,71 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe ActivityPub::Activity do
+  describe 'processing a Create and an Update' do
+    let(:sender) { Fabricate(:account, followers_url: 'http://example.com/followers', domain: 'example.com', uri: 'https://example.com/actor') }
+
+    let(:create_json) do
+      {
+        '@context': [
+          'https://www.w3.org/ns/activitystreams',
+        ],
+        id: [ActivityPub::TagManager.instance.uri_for(sender), '#create'].join,
+        type: 'Create',
+        actor: ActivityPub::TagManager.instance.uri_for(sender),
+        object: {
+          id: [ActivityPub::TagManager.instance.uri_for(sender), 'post1'].join('/'),
+          type: 'Note',
+          to: [
+            'https://www.w3.org/ns/activitystreams#Public',
+          ],
+          content: 'foo',
+          published: '2025-05-24T11:03:10Z',
+        },
+      }.deep_stringify_keys
+    end
+
+    let(:update_json) do
+      {
+        '@context': [
+          'https://www.w3.org/ns/activitystreams',
+        ],
+        id: [ActivityPub::TagManager.instance.uri_for(sender), '#update'].join,
+        type: 'Update',
+        actor: ActivityPub::TagManager.instance.uri_for(sender),
+        object: {
+          id: [ActivityPub::TagManager.instance.uri_for(sender), 'post1'].join('/'),
+          type: 'Note',
+          to: [
+            'https://www.w3.org/ns/activitystreams#Public',
+          ],
+          content: 'bar',
+          updated: '2025-05-25T11:03:10Z',
+        },
+      }.deep_stringify_keys
+    end
+
+    before do
+      sender.update(uri: ActivityPub::TagManager.instance.uri_for(sender))
+    end
+
+    context 'when getting them in order' do
+      it 'creates a status with the edited contents' do
+        described_class.factory(create_json, sender).perform
+        status = described_class.factory(update_json, sender).perform
+
+        expect(status.text).to eq 'bar'
+      end
+    end
+
+    context 'when getting them out of order' do
+      it 'creates a status with the edited contents' do
+        described_class.factory(update_json, sender).perform
+        status = described_class.factory(create_json, sender).perform
+
+        expect(status.text).to eq 'bar'
+      end
+    end
+  end
+end