Request tests fail after upgrading to Rails 5

Before Rails 5, I used to write “request specs” using rspec as below:

describe Api::Apps::Show do

  describe 'GET /api/apps/:id' do

    it 'responds with 200' do

      headers = { 
        'Authorization' => "Bearer #{auth_token}",  
        "Content-Type" => "application/vnd.api+json",
        "Accept" => "application/json"
      }

      get url, nil, headers
      expect(response.status).to eq(200)
    end

  end

end

After upgrading to Rails 5, when I run the spec above I got the following error:

ArgumentError: wrong number of arguments (given 3, expected 1)

According to the error message above, get method expects 1 argument instead of 3. Trying to debug the error was redirected me to actionpack-5.1.3/lib/action_dispatch/testing/integration.rb file. I found the definition of get method around line 15:

def get(path, **args)
  process(:get, path, **args)
end

Replacing the get method call in the spec code as below solved the problem:

get url, params: nil, headers: headers

See this stackoverflow post how to use splat and double splat.