language: ruby
env:
  - ARUBA_TIMEOUT=240
before_install:
  - gem update --system
  - rvm @default,@global do gem uninstall bundler -v 2.0.1 -x
cache: bundler
rvm:
  - 2.3
  - 2.4
  - 2.5
  - 2.6
  - ruby-head
branches:
  only:
    - master
install:
  - "bundle install --retry 3 --jobs 8"
gemfile:
  - gemfiles/rails4.2.gemfile
  - gemfiles/rails5.0.gemfile
  - gemfiles/rails5.1.gemfile
  - gemfiles/rails5.2.gemfile
  - gemfiles/rails6.0.gemfile
matrix:
  fast_finish: true
  allow_failures:
    - rvm: ruby-head
  exclude:
    - rvm: 2.3
      gemfile: gemfiles/rails6.0.gemfile
    - rvm: 2.4
      gemfile: gemfiles/rails6.0.gemfile

language: ruby
env:
  - ARUBA_TIMEOUT=240
before_install:
  - gem update --system
  - rvm @default,@global do gem uninstall bundler -v 2.0.2 -x
cache: bundler
rvm:
  - 2.3
  - 2.4
  - 2.5
  - 2.6
  - ruby-head
branches:
  only:
    - master
install:
  - "bundle install --retry 3 --jobs 8"
gemfile:
  - gemfiles/rails4.2.gemfile
  - gemfiles/rails5.0.gemfile
  - gemfiles/rails5.1.gemfile
  - gemfiles/rails5.2.gemfile
  - gemfiles/rails6.0.gemfile
matrix:
  fast_finish: true
  allow_failures:
    - rvm: ruby-head
  exclude:
    - rvm: 2.3
      gemfile: gemfiles/rails6.0.gemfile
    - rvm: 2.4
      gemfile: gemfiles/rails6.0.gemfile

Address `Bundler could not find compatible versions for gem "bundler":`
Address `Bundler could not find compatible versions for gem "bundler":`

https://travis-ci.org/thoughtbot/factory_bot_rails/jobs/567563177#L333-L355

```ruby
Bundler could not find compatible versions for gem "bundler":
  In rails4.2.gemfile:
    appraisal was resolved to 2.2.0, which depends on
      bundler

    rails (~> 4.2.11) was resolved to 4.2.11.1, which depends on
      bundler (>= 1.3.0, < 2.0)

  Current Bundler version:
    bundler (2.0.2)
This Gemfile requires a different version of Bundler.
Perhaps you need to update Bundler by running `gem install bundler`?

Could not find gem 'bundler (>= 1.3.0, < 2.0)', which is required by gem 'rails
(~> 4.2.11)', in any of the sources.

Bundler could not find compatible versions for gem "cucumber":
  In rails4.2.gemfile:
    cucumber (= 1.3.19)

    aruba was resolved to 0.14.11, which depends on
      cucumber (>= 1.3.19)
The command "bundle install --retry 3 --jobs 8" failed and exited with 6 during .
```

because the latest version of Bundler is 2.0.2 since June 13, 2019

https://rubygems.org/gems/bundler/versions/2.0.2
