[rspec] Grape APIのhelpersをスタブ化するメモ

grape 1.3.3
rspec-rails 5.0.1

grape使っている際, current_userのようなよく使うものへスタブ差し込む方法が分からなかったのでメモ

諸々省略

app/apis/my_service/api.rb

class MyService::Api < Grape::API
  # 省略
  helpers do
    def current_user
      @current_user ||= User.find(params[:id])
    end
  end
end

spec/app/apis/my_service/v1/users_spec.rb

describe MyService::V1::Users do
  describe "GET /my_service/v1/user/:id" do
    subject { get "/my_service/v1/user/#{user.id}" }

    let(:user) { create(:user) }
    context "no good" do
      before do
        allow(User).to receive(:find).and_return(user)
      end
      it 'response user' do
        subject
        expect(my_response[:name]).to eq user.name
        ...
      end
    end
    context "good" do
      before do
        Grape::Endpoint.before_each do |endpoint|
          allow(endpoint).to receive(:current_user).and_return(user)
        end
      end
      after { Grape::Endpoint.before_each nil }

      it 'response user' do
        subject
        expect(my_response[:name]).to eq user.name
        ...
      end      
    end
  end
end

参考
https://github.com/ruby-grape/grape/issues/396