test.host in Rspec testing Rails redirect - ruby-on-rails

Question

Here's a line from my test.rb environnment file in a Rails 3.1.12 app:
config.action_mailer.default_url_options = config.action_controller.default_url_options = { :host => "127.0.0.1", :port => 3000 }
Now here's the test I make:
subject { get :success }
subject.should redirect_to(:home)
This produces an error:
Failure/Error: subject.should redirect_to(:home)
Expected response to be a redirect to <http://127.0.0.1:3000/> but was a redirect to <http://test.host/>
What did I do wrong? Or else, where the testing host be configured?
Here's the spec_helper.rb file for complete reference.
# This file is copied to spec/ when you run 'rails generate rspec:install'
ENV["RAILS_ENV"] = 'test'
require File.expand_path("../../config/environment", __FILE__)
require 'rspec/rails'
require 'rspec/autorun'
require 'capybara/rspec'
# Requires supporting ruby files with custom matchers and macros, etc,
# in spec/support/ and its subdirectories.
Dir[Rails.root.join("spec/support/**/*.rb")].each {|f| require f}
RSpec.configure do |config|
# ## Mock Framework
#
# If you prefer to use mocha, flexmock or RR, uncomment the appropriate line:
#
# config.mock_with :mocha
# config.mock_with :flexmock
# config.mock_with :rr
# Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
config.fixture_path = "#{::Rails.root}/spec/fixtures"
# If you're not using ActiveRecord, or you'd prefer not to run each of your
# examples within a transaction, remove the following line or assign false
# instead of true.
config.use_transactional_fixtures = true
# If true, the base class of anonymous controllers will be inferred
# automatically. This will be the default behavior in future versions of
# rspec-rails.
config.infer_base_class_for_anonymous_controllers = false
# Run specs in random order to surface order dependencies. If you find an
# order dependency and want to debug it, you can fix the order by providing
# the seed, which is printed after each run.
# --seed 1234
config.order = "random"
end
Capybara.configure do |config|
config.app_host = 'http://127.0.0.1'
config.server_port = 3000
end

Answer 1

This worked for me:
# spec/controllers/whatever_controller_spec.rb
before :each do
#request.host = '127.0.0.1:3000'
end
Based on the link #dan-reedy supplied. It is sublimely annoying to have to configure the exact same parameters in config/environments, spec/spec_helper.rb and again here... all in marginally different ways (with 'http://' or without, with port number or port specified separately). Even Capybara.configure syntax can't seem to stay consistent to itself between versions...
But give it a try and see if that solves it.

Answer 2

Here's the workaround that seems to have fixed the issue for me:
In spec/rails_helper.rb add this
module ActionDispatch
class TestRequest
# Override host, by default it is test.host
def host
'localhost:3000'
end
end
end

Answer 3

To set the app host and server port with Capybara add the following lines to your spec/spec_helper.rb file
Capybara.configure do |config|
config.app_host = 'http://127.0.0.1'
config.server_port = 3000
end
-- Edit #1
A nice overview of testing domains is available at http://blog.joncairns.com/2012/12/testing-domains-with-rails-and-test-unit/