Fix Rails 4.0 tests

.travis.yml

@@ -8,15 +8,13 @@ rvm:
   - 2.0.0
   - rbx-19mode
   - jruby-19mode
-  - ruby-head
 
 env:
+  - "RAILS_VERSION=4.0"
   - "RAILS_VERSION=3.2"
   - "RAILS_VERSION=3.1"
   - "RAILS_VERSION=3.0"
-  - "RAILS_VERSION=master"
 
 matrix:
   allow_failures:
-    - rvm: ruby-head
-    - env: "RAILS_VERSION=master"
+    - env: "RAILS_VERSION=4.0"

Gemfile

@@ -13,27 +13,4 @@ end
 
 version = ENV["RAILS_VERSION"] || "3.2"
 
-rails = case version
-when "master"
-  {github: "rails/rails"}
-else
-  "~> #{version}.0"
-end
-
-mongoid = case version
-when "master"
-  {github: "mongoid/mongoid"}
-when "3.2"
-  "~> 3.1.0"
-when "3.1"
-  "~> 3.0.0"
-end
-
-devise = case version
-when "3.1", "3.2"
-  "~> 2.2"
-end
-
-gem "rails", rails
-gem "mongoid", mongoid if mongoid
-gem "devise", devise if devise
+eval_gemfile File.expand_path("../gemfiles/#{version}.gemfile", __FILE__)

gemfiles/3.0.gemfile

@@ -0,0 +1 @@
+gem "rails", "~> 3.0.0"

gemfiles/3.1.gemfile

@@ -0,0 +1,3 @@
+gem "rails", "~> 3.1.0"
+gem "mongoid", "~> 3.0.0"
+gem "devise", "~> 2.2"

gemfiles/3.2.gemfile

@@ -0,0 +1,3 @@
+gem "rails", "~> 3.2.0"
+gem "mongoid", "~> 3.1.0"
+gem "devise", "~> 2.2"

gemfiles/4.0.gemfile

@@ -0,0 +1,3 @@
+gem "rails", github: "rails/rails", branch: "4-0-0"
+gem "mongoid", github: "mongoid/mongoid"
+gem "devise", github: "plataformatec/devise"