mastodon/spec/controllers/activitypub/outboxes_controller_spec.rb

require 'rails_helper'

RSpec.describe ActivityPub::OutboxesController, type: :controller do
  let!(:account) { Fabricate(:account) }

  before do
    Fabricate(:status, account: account)
  end

  describe 'GET #show' do
    before do
      get :show, params: { account_username: account.username }
    end

    it 'returns http success' do
      expect(response).to have_http_status(200)
    end

    it 'returns application/activity+json' do
      expect(response.content_type).to eq 'application/activity+json'
    end
  end
end