Fix Update/Delete of quoted status not being forwarded to quoters's followers (#36390)

app/lib/activitypub/forwarder.rb

@@ -27,17 +27,25 @@ class ActivityPub::Forwarder
     @reblogged_by_account_ids ||= @status.reblogs.includes(:account).references(:account).merge(Account.local).pluck(:account_id)
   end
 
+  def quoted_by_account_ids
+    @quoted_by_account_ids ||= @status.quotes.includes(:account).references(:account).merge(Account.local).pluck(:account_id)
+  end
+
+  def shared_by_account_ids
+    reblogged_by_account_ids.concat(quoted_by_account_ids)
+  end
+
   def signature_account_id
     @signature_account_id ||= if in_reply_to_local?
                                 in_reply_to.account_id
                               else
-                                reblogged_by_account_ids.first
+                                shared_by_account_ids.first
                               end
   end
 
   def inboxes
     @inboxes ||= begin
-      arr  = inboxes_for_followers_of_reblogged_by_accounts
+      arr  = inboxes_for_followers_of_shared_by_accounts
       arr += inboxes_for_followers_of_replied_to_account if in_reply_to_local?
       arr -= [@account.preferred_inbox_url]
       arr.uniq!
@@ -45,8 +53,8 @@ class ActivityPub::Forwarder
     end
   end
 
-  def inboxes_for_followers_of_reblogged_by_accounts
+  def inboxes_for_followers_of_shared_by_accounts
-    Account.where(id: ::Follow.where(target_account_id: reblogged_by_account_ids).select(:account_id)).inboxes
+    Account.where(id: ::Follow.where(target_account_id: shared_by_account_ids).select(:account_id)).inboxes
   end
 
   def inboxes_for_followers_of_replied_to_account

spec/lib/activitypub/forwarder_spec.rb

@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe ActivityPub::Forwarder do
+  subject { described_class.new(account, payload, status) }
+
+  let(:account) { Fabricate(:account) }
+  let(:remote_account) { Fabricate(:account, domain: 'example.com') }
+  let(:status) { Fabricate(:status, account: remote_account) }
+
+  let(:signature) { { type: 'RsaSignature2017', signatureValue: 'foo' } }
+  let(:payload) do
+    {
+      '@context': [
+        'https://www.w3.org/ns/activitystreams',
+        'https://w3id.org/security/v1',
+      ],
+      signature: signature,
+      type: 'Delete',
+      object: ActivityPub::TagManager.instance.uri_for(status),
+    }.deep_stringify_keys
+  end
+
+  describe '#forwardable?' do
+    context 'when payload has an inlined signature' do
+      it 'returns true' do
+        expect(subject.forwardable?).to be true
+      end
+    end
+
+    context 'when payload has an no inlined signature' do
+      let(:signature) { nil }
+
+      it 'returns true' do
+        expect(subject.forwardable?).to be false
+      end
+    end
+  end
+
+  describe '#forward!' do
+    let(:alice) { Fabricate(:account) }
+    let(:bob) { Fabricate(:account) }
+    let(:eve) { Fabricate(:account, domain: 'remote1.example.com', inbox_url: 'https://remote1.example.com/users/eve/inbox', protocol: :activitypub) }
+    let(:mallory) { Fabricate(:account, domain: 'remote2.example.com', inbox_url: 'https://remote2.example.com/users/mallory/inbox', protocol: :activitypub) }
+
+    before do
+      alice.statuses.create!(reblog: status)
+      Fabricate(:quote, status: Fabricate(:status, account: bob), quoted_status: status, state: :accepted)
+
+      eve.follow!(alice)
+      mallory.follow!(bob)
+    end
+
+    it 'correctly forwards to expected remote followers' do
+      expect { subject.forward! }
+        .to enqueue_sidekiq_job(ActivityPub::LowPriorityDeliveryWorker).with(Oj.dump(payload), anything, eve.preferred_inbox_url)
+        .and enqueue_sidekiq_job(ActivityPub::LowPriorityDeliveryWorker).with(Oj.dump(payload), anything, mallory.preferred_inbox_url)
+    end
+  end
+end