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
    - 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, ruby-2.7, 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

Supported Version Syntax

• engine-version like ruby-2.6.5 and truffleruby-19.3.0
• short version like 2.6, automatically using the latest release matching that version (2.6.5)
• version only like 2.6.5, assumes MRI for the engine
• engine only like truffleruby, uses the latest stable release of that implementation

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, 2.5, 2.6, 2.7, 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.