Switch sessions when the subdomain is switched

Credit: http://www.automation-excellence.com/blog/racking-my-brains

spec/acceptance/subdomains_spec.rb

@@ -12,18 +12,22 @@
   end
 
   scenario "Access subdomain one" do
-    Capybara.default_host = "one.example.com"
-    Capybara.app_host     = "http://one.example.com"
+    set_subdomain("one")
     visit '/'
     current_url.should == "http://one.example.com/" # passes
-    find("h1").text.should == "http://one.example.com/" # fails with envjs
+    find("h1").text.should == "http://one.example.com/" # passes
   end
 
   scenario "Access subdomain two" do
-    Capybara.default_host = "two.example.com"
-    Capybara.app_host     = "http://two.example.com"
+    set_subdomain("two")
     visit '/'
     current_url.should == "http://two.example.com/" # passes
-    find("h1").text.should == "http://two.example.com/" # fails with envjs
+    find("h1").text.should == "http://two.example.com/" # passes
+  end
+
+  def set_subdomain(subdomain)
+    Capybara.default_host = "#{subdomain}.example.com"
+    Capybara.app_host     = "http://#{subdomain}.example.com"
+    switch_session(subdomain)
   end
 end

spec/acceptance/support/helpers.rb

@@ -1,5 +1,16 @@
 module HelperMethods
-  # Put helper methods you need to be available in all tests here.
+  def set_session(id)
+    Capybara.instance_variable_set('@session_pool', {
+     "#{Capybara.current_driver}#{Capybara.app.object_id}" => $sessions[id]
+    })
+  end
+
+  def switch_session(id)
+    $sessions ||= {}
+    $sessions[:default] ||= Capybara.current_session
+    $sessions[id]       ||= Capybara::Session.new(Capybara.current_driver, Capybara.app)
+    set_session(id)
+  end
 end
 
 RSpec.configuration.include HelperMethods, :type => :acceptance