Updating ruby version
The reason for doing so is to bring it to developers attention that their project may have dependencies that should not be used on JRuby in production.Using C extensions on JRuby is technically possible but is not a good idea performance and stability-wise and we believe continuous integration services like Travis CI should highlight it.You can tell Travis CI to cache the installed bundle. On the second one, we’ll pull in the cache, making in their default set of gems.This slows down the installation process quite a lot, and commonly, those libraries aren’t needed when running your tests.On January 3rd 2019 the Bundler team released Bundler 2.0 which dropped support for Ruby versions 2.2 and older, and added a new dependency on Ruby Gems 3.0.0.A subsequent release, 2.0.1, requires Ruby Gems 2.5.0.Edit: Another way to go without bumping the Ruby version is to update rubygems itself (gem update --system), but I’m not sure if that’s possible early in the build / setup process.
Travis CI uses Bundler to install your Ruby project’s dependencies if there is a Gemfile in the project’s root directory, or if there is a Gemfile specified in the build matrix: By default, gems are installed into vendor/bundle in your project’s root directory.
The same is true for gems that you only need in production, like Unicorn, the New Relic library, and the like.