use-ruby

This action downloads a prebuilt ruby and adds it to $PATH.

It currently supports the latest stable versions of MRI, JRuby and TruffleRuby.

See https://github.com/eregon/ruby-install-builder/blob/metadata/versions.json for the available Ruby versions.

The action works for the ubuntu-16.04, ubuntu-18.04 and macos-latest GitHub-hosted runners.
windows-latest is not yet supported.

The prebuilt rubies are generated by https://github.com/eregon/ruby-install-builder.

Usage

Single Job

name: My workflow
on: [push]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v2
    - uses: eregon/use-ruby-action@master
      with:
        ruby-version: ruby-2.6.5
    - run: ruby -v

Matrix

name: My workflow
on: [push]
jobs:
  test:
    strategy:
      fail-fast: false
      matrix:
        os: [ 'ubuntu-latest', 'macos-latest' ]
        ruby: [ 'ruby-2.6.5', 'ruby-2.7.0', 'truffleruby-19.3.0', 'jruby-9.2.9.0' ]
    runs-on: ${{ matrix.os }}
    steps:
    - uses: actions/checkout@v2
    - uses: eregon/use-ruby-action@master
      with:
        ruby-version: ${{ matrix.ruby }}
    - run: ruby -v

If a specific version is not given, it uses the latest stable release of that implementation. For instance truffleruby is currently the same as truffleruby-19.3.0.

If it's just a version number (e.g., 2.6.5), then MRI is assumed (same as ruby-2.6.5).

All Stable Versions

With that, we can test on all stable releases of MRI, JRuby and TruffleRuby with:

name: My workflow
on: [push]
jobs:
  test:
    strategy:
      fail-fast: false
      matrix:
        os: [ 'ubuntu-latest', 'macos-latest' ]
        ruby: [ '2.4.9', '2.5.7', '2.6.5', '2.7.0', 'truffleruby', 'jruby' ]
    runs-on: ${{ matrix.os }}
    steps:
    - uses: actions/checkout@v2
    - uses: eregon/use-ruby-action@master
      with:
        ruby-version: ${{ matrix.ruby }}
    - run: ruby -v

Efficiency

It takes about 5 seconds to setup the given Ruby.

Limitations

• Currently does not work on Windows since the builder doesn't build on Windows. https://github.com/MSP-Greg/actions-ruby is an alternative on Windows.
• This action currently only works with GitHub-hosted runners, not private runners.