Gemfile in community_engine-2.3.0 vs Gemfile in community_engine-2.3.1

@@ -4,6 +4,20 @@
 
 group :test do
   gem 'sqlite3'
 end
 
-gemspec
\ No newline at end of file
+rails_version = ENV["RAILS_VERSION"] || "default"
+
+rails = case rails_version
+when "master"
+  {github: "rails/rails"}
+when "default"
+  ">= 3.2.0"
+else
+  "~> #{rails_version}"
+end
+
+gem "rails", rails
+
+
+gemspec