language: ruby
rvm:
  - 2.3.0
  - 2.4.0
  - 2.5.0
before_install: gem install bundler -v 1.16.1

language: ruby
rvm:
  - 2.3.0
  - 2.4.0
  - 2.5.0
  - 2.6.0-preview1
before_install: gem install bundler -v 1.16.1

Add Ruby 2.6.0-preview1 to Travis CI test matrix
Add Ruby 2.6.0-preview1 to Travis CI test matrix
