Add handler for Move activity (#9629)

spec/lib/activitypub/activity/move_spec.rb

@@ -0,0 +1,52 @@
+require 'rails_helper'
+
+RSpec.describe ActivityPub::Activity::Move do
+  let(:follower)    { Fabricate(:account) }
+  let(:old_account) { Fabricate(:account) }
+  let(:new_account) { Fabricate(:account) }
+
+  before do
+    follower.follow!(old_account)
+
+    old_account.update!(uri: 'https://example.org/alice', domain: 'example.org', protocol: :activitypub, inbox_url: 'https://example.org/inbox')
+    new_account.update!(uri: 'https://example.com/alice', domain: 'example.com', protocol: :activitypub, inbox_url: 'https://example.com/inbox', also_known_as: [old_account.uri])
+
+    stub_request(:post, 'https://example.org/inbox').to_return(status: 200)
+    stub_request(:post, 'https://example.com/inbox').to_return(status: 200)
+
+    service_stub = double
+    allow(ActivityPub::FetchRemoteAccountService).to receive(:new).and_return(service_stub)
+    allow(service_stub).to receive(:call).and_return(new_account)
+  end
+
+  let(:json) do
+    {
+      '@context': 'https://www.w3.org/ns/activitystreams',
+      id: 'foo',
+      type: 'Move',
+      actor: old_account.uri,
+      object: old_account.uri,
+      target: new_account.uri,
+    }.with_indifferent_access
+  end
+
+  describe '#perform' do
+    subject { described_class.new(json, old_account) }
+
+    before do
+      subject.perform
+    end
+
+    it 'sets moved account on old account' do
+      expect(old_account.reload.moved_to_account_id).to eq new_account.id
+    end
+
+    it 'makes followers unfollow old account' do
+      expect(follower.following?(old_account)).to be false
+    end
+
+    it 'makes followers follow-request the new account' do
+      expect(follower.requested?(new_account)).to be true
+    end
+  end
+end