While testing Devise with rspec, it acts like I am not logged in - ruby-on-rails-3

Question

I'm using Rails 3.2.13, devise 2.2.4, and rspec 2.13.2. I have a multi-tenant app in which the default scope only shows current_user's items. Everything seems to work in development, but my tests are having issues.
Problem: When I create a meal in my test, it shows user_id => nil. In my development environment everything works, though. Also, when I go into debug mode, when I check the #controller.current_user, it shows user_id 1 is logged in. Since in my development environment the user_id is being assigned automatically when I create an object, I can't figure out why it's not doing it during tests. Any ideas?
Here's my abbreviated meals_controller_spec file:
describe MealsController do
include Devise::TestHelpers
describe "When logged in as user," do
before(:each) do
#request.env["devise.mapping"] = Devise.mappings[:user]
#email = "someone#test.com"
#password = "password"
#user = User.create(email: #email, password: #password)
sign_in #user
end
describe "DELETE destroy" do
it "destroys the requested meal" do
meal = Meal.create!("name" => "", "servings" => "2", "meal_type" => "dinner")
expect { delete 'destroy', {:id => meal.id} }.to change(Meal, :count).by(-1)
end
end
end
end
Here's part of my model:
class Meal < ActiveRecord::Base
belongs_to :user
default_scope { where(user_id: User.current_id) }
Here's part of my controller:
class MealsController < ApplicationController
before_filter :authenticate_user!
def destroy
#meal = Meal.find(params[:id])
#meal.destroy
redirect_to meals_url, :notice => "Successfully deleted #{#meal.name}."
end
end
And I think my application controller could be relevant:
class ApplicationController < ActionController::Base
protect_from_forgery
around_filter :scope_current_tenant
private
def scope_current_tenant
User.current_id = current_user.id
yield
rescue Exception
yield
ensure
User.current_id = nil
end
end
Here's some output when I debug in the middle of that test:
(rdb:1) #controller.current_user.id
1
(rdb:1) Meal.create!(name: "meal", meal_type: "dinner", servings: 2)
#<Meal id: 2, name: "meal", meal_type: "dinner", servings: 2, user_id: nil, created_at: "2013-06-17 06:07:34", updated_at: "2013-06-17 06:07:34">
(rdb:1) Meal.create!(name: "meal", meal_type: "dinner", servings: 2, user_id: 1)
#<Meal id: 3, name: "meal", meal_type: "dinner", servings: 2, user_id: 1, created_at: "2013-06-17 06:12:18", updated_at: "2013-06-17 06:12:18">
(rdb:1) Meal.find(3).destroy
*** NoMethodError Exception: undefined method `destroy' for nil:NilClass
So I guess I'm wondering why the user in my test appears to be nil, even though I am using the Devise test helpers and signing in, and in my dev environment everything works.
Edit:
Here are some more debugger results:
(rdb:1) Meal.find(4)
*** ActiveRecord::RecordNotFound Exception: Couldn't find Meal with id=4 [WHERE "meals"."user_id" IS NULL]
(rdb:1) Meal.find(4).destroy
*** ActiveRecord::RecordNotFound Exception: Couldn't find Meal with id=4 [WHERE "meals"."user_id" IS NULL]
(rdb:1) Meal.where(:user_id => 1).find(3)
#<Meal id: 3, name: "meal", meal_type: "dinner", servings: 2, user_id: 1, created_at: "2013-06-17 06:12:18", updated_at: "2013-06-17 06:12:18">
It appears that the "current user" is in fact user_id => nil, per the sql snippets. So why would that be if I used the Devise test helper sign_in function?