```ruby
require 'rails_helper'

describe Admin::BaseController do
  controller(Admin::BaseController) do
    def index
      render text: 'index body'
    end
  end

  let(:account) { create :account }

  before do
    controller.stub(:setup_request)
  end
  before { @request.env['HTTPS'] = 'on' }

  it 'redirects to engine authentication path' do
    get :index
    expect(response.body).to include '/auth/bookingsync/?account_id='
  end

  context 'when ssl not used' do
    before { @request.env['HTTPS'] = nil }

    it 'forces ssl' do
      get :index
      expect(response).to redirect_to 'https://test.host/admin/base'
    end
  end

  context 'when X-Frame-Options is set' do
    before do
      allow(controller).to receive(:current_account).and_return(account)
    end

    it 'allows to be run in iframe' do
      request.headers['X-Frame-Options'] = 'SAMEORIGIN'
      get :index
      expect(response.headers['X-Frame-Options']).to eq ''
    end
  end

  context 'with authenticated account' do
    before do
      allow(controller).to receive(:current_account).and_return(account)
    end

    it 'has context set with current_account' do
      expect(controller.send(:context)).to eq(current_account: account)
    end
  end

  it 'is JSONAPI::ResourceController controller' do
    expect(controller).to be_kind_of JSONAPI::ResourceController
  end
end
```

Fix RSpec deprecation by removing stub
user
```ruby
require 'rails_helper'

describe Admin::BaseController do
  controller(Admin::BaseController) do
    def index
      render text: 'index body'
    end
  end

  let(:account) { create :account }

  before do
    allow(controller).to receive(:setup_request)
  end
  before { @request.env['HTTPS'] = 'on' }

  it 'redirects to engine authentication path' do
    get :index
    expect(response.body).to include '/auth/bookingsync/?account_id='
  end

  context 'when ssl not used' do
    before { @request.env['HTTPS'] = nil }

    it 'forces ssl' do
      get :index
      expect(response).to redirect_to 'https://test.host/admin/base'
    end
  end

  context 'when X-Frame-Options is set' do
    before do
      allow(controller).to receive(:current_account).and_return(account)
    end

    it 'allows to be run in iframe' do
      request.headers['X-Frame-Options'] = 'SAMEORIGIN'
      get :index
      expect(response.headers['X-Frame-Options']).to eq ''
    end
  end

  context 'with authenticated account' do
    before do
      allow(controller).to receive(:current_account).and_return(account)
    end

    it 'has context set with current_account' do
      expect(controller.send(:context)).to eq(current_account: account)
    end
  end

  it 'is JSONAPI::ResourceController controller' do
    expect(controller).to be_kind_of JSONAPI::ResourceController
  end
end
```
assistant