rvm:
  - 2.1
  - 2.2
  - 2.3.1
  - 2.4
  - 2.5
branches:
  only:
    - master
before_install:
  - gem uninstall -v '>= 2' -i $(rvm gemdir)@global -ax bundler || true
  - gem install bundler -v '< 2'

dist: xenial
os: linux
language: ruby
rvm:
  - 2.1
  - 2.2
  - 2.3
  - 2.4
  - 2.5
  - 2.6
  - 2.7
  - ruby-edge
branches:
  only:
    - master
before_install:
  - gem uninstall -v '>= 2' -i $(rvm gemdir)@global -ax bundler || true
  - gem install bundler -v '< 2'
jobs:
  allow_failures:
  - rvm: ruby-edge

Test against Ruby 2.6, 2.7, and edge
Test against Ruby 2.6, 2.7, and edge

Also improves Travis CI configuration by specifying `dist`, `os`, and
`language` parameters