Ruby on Rails difference between cookies[:remember_token] and cookies["remember_token"]

Question

I have trouble undestanding the following situation:

I am logging in and remembering my users by doing the following

class SessionsController < ApplicationController

  def create
    user=User.find_by(email: params[:session][:email])
    if user && user.authenticate(params[:session][:password])
      log_in(user)
      params[:session][:remember_me]=="1" ? remember(user) : forget(user)
      redirect_to user
    else
      flash.now[:danger]="Invalid email/password combination"
      render "new"
    end
  end

and

module SessionsHelper

    def remember(user)
        user.remember
        cookies.permanent.signed[:user_id]=user.id
        cookies.permanent[:remember_token]=user.remember_token
    end

all of which works fine. The thing that I don't understand though, is that in an integration test I have to use cookies["remember_token"] because in the following situation cookies[:remember_token] will return nil

test "login with remember_me" do
    log_in_as(@user)
    assert_not_nil cookies["remember_token"]
end

Why does it return nil here and why does it not do that, if I use it for example as a parameter in a function inside of the Sessionhelper ( for example user.authenticated?(cookies[:remember_token]) )

P.S.: All of the code above comes from the Ruby on Rails Tutorial by Michael Hartl https://www.railstutorial.org/book (chap. 9.3.1)

Answer 1

This is because in normal application cookies method returns ActionDispatch::Cookies::CookieJar object which always converts cookie names to string. In integration test, cookies method returns Rack::Test::CookieJar object which doesn't do such conversion. So if you set your cookie in tests via symbol you need to access it via symbol. The same goes if you set your cookie via string.