Gemfile in mongoid-history-0.4.1 vs Gemfile in mongoid-history-0.4.2

@@ -1,16 +1,12 @@
-source "http://rubygems.org"
-
-gem "easy_diff"
-gem "mongoid", ">= 3.0"
-gem "activesupport"
-
-group :test do
-  gem "rspec", ">= 2.11.0"
-  gem "bundler", ">= 1.0.0"
-end
-
-group :development do
-  gem 'rubocop', '~> 0.15.0'
-  gem "yard"
-  gem "jeweler"
-end
+source 'https://rubygems.org'
+
+gemspec
+
+case version = ENV['MONGOID_VERSION'] || '~> 4.0'
+when /4/
+  gem 'mongoid', '~> 4.0'
+when /3/
+  gem 'mongoid', '~> 3.1'
+else
+  gem 'mongoid', version
+end