Gemfile in github-ds-0.4.0 vs Gemfile in github-ds-0.5.0

@@ -1,12 +1,18 @@
 source "https://rubygems.org"
 gemspec
 
-DEFAULT_RAILS_VERSION = '5.0.2'
+DEFAULT_RAILS_VERSION = '6.0.3'
+ENV['RAILS_VERSION'] ||= DEFAULT_RAILS_VERSION
 
-if ENV['RAILS_VERSION'] = '4.2.10'
+if ENV['RAILS_VERSION'] == '4.2.10'
   gem 'mysql2', '~> 0.3.18'
 else
   gem "mysql2"
 end
-gem "rails", "~> #{ENV['RAILS_VERSION'] || DEFAULT_RAILS_VERSION}"
-gem "activerecord", "~> #{ENV['RAILS_VERSION'] || DEFAULT_RAILS_VERSION}"
+
+if ENV['RAILS_VERSION'] == 'master'
+  gem "activerecord", git: "https://github.com/rails/rails"
+else
+  gem "rails", "~> #{ENV['RAILS_VERSION'] || DEFAULT_RAILS_VERSION}"
+  gem "activerecord", "~> #{ENV['RAILS_VERSION'] || DEFAULT_RAILS_VERSION}"
+end