document cache-version

* See https://github.com/ruby/setup-ruby/issues/171
  and https://github.com/oneclick/rubyinstaller/issues/400

.eslintrc.json

@@ -1,18 +0,0 @@
-{
-    "env": {
-        "commonjs": true,
-        "es6": true,
-        "node": true
-    },
-    "extends": "eslint:recommended",
-    "globals": {
-        "Atomics": "readonly",
-        "SharedArrayBuffer": "readonly"
-    },
-    "parserOptions": {
-        "ecmaVersion": 2018,
-        "sourceType": "module"
-    },
-    "rules": {
-    }
-}

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,21 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+<!--
+Before filing this issue:
+* Make sure you use the latest version with `- uses: ruby/setup-ruby@v1` (see https://github.com/ruby/setup-ruby/blob/master/README.md#versioning)
+* If the issue happens on JRuby or TruffleRuby, and does not happen on CRuby (please check), file an issue there instead. It's very unlikely ruby/setup-ruby is the cause.
+* Try to reproduce the issue locally by following the workflow steps (including all commands done by ruby/setup-ruby, except for `Downloading Ruby` & `Extracting Ruby`). If it does reproduce locally, it's not a ruby/setup-ruby issue.
+
+Please provide:
+* the code of or a link to the workflow used
+* the link to the log of a failed workflow job
+* the command and output of the step failing
+* whether you are using a self-hosted runner
+-->

.github/workflows/release.yml

@@ -0,0 +1,12 @@
+name: Update the v1 branch when a release is published
+on:
+  release:
+    types: [published]
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        fetch-depth: 0
+    - run: git push origin HEAD:v1

.github/workflows/test.yml

@@ -1,5 +1,6 @@
 name: Test this action
 on:
+  pull_request:
   push:
     branches-ignore:
     - v1
@@ -7,47 +8,157 @@ on:
     - '*'
     paths-ignore:
     - README.md
+  schedule:
+    - cron: '0 7 * * SUN'
 jobs:
   test:
     strategy:
       fail-fast: false
       matrix:
-        os: [ ubuntu-16.04, ubuntu-18.04, macos-latest, windows-latest ]
-        # Use various version syntaxes here for testing
-        ruby: [ .ruby-version, 2.3, ruby-2.4, 2.5, ruby-2.6.5, 2.7.0, jruby, truffleruby, truffleruby-head, rubinius ]
+        os: [ ubuntu-18.04, ubuntu-20.04, macos-10.15, macos-11.0, windows-2016, windows-2019 ]
+        ruby: [ 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, '3.0', ruby-head, jruby, jruby-head, truffleruby, truffleruby-head ]
+        include:
+        - { os: windows-2016, ruby: mingw }
+        - { os: windows-2019, ruby: mingw }
+        - { os: windows-2019, ruby: mswin }
         exclude:
-        - os: windows-latest
-          ruby: truffleruby
-        - os: windows-latest
-          ruby: truffleruby-head
-        - os: ubuntu-16.04
-          ruby: rubinius
-        - os: macos-latest
-          ruby: rubinius
-        - os: windows-latest
-          ruby: rubinius
+        - { os: windows-2016, ruby: debug }
+        - { os: windows-2016, ruby: truffleruby }
+        - { os: windows-2016, ruby: truffleruby-head }
+        - { os: windows-2019, ruby: debug }
+        - { os: windows-2019, ruby: truffleruby }
+        - { os: windows-2019, ruby: truffleruby-head }
+
+    name: ${{ matrix.os }} ${{ matrix.ruby }}
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v2
+
+    - uses: ./
+      with:
+        ruby-version: ${{ matrix.ruby }}
+        bundler-cache: true
+    - run: ruby -v
+    - name: PATH
+      shell: bash
+      run: echo $PATH
+
+    - name: build compiler
+      run: |
+        ruby -e "puts 'build compiler: ' + RbConfig::CONFIG.fetch('CC_VERSION_MESSAGE', 'unknown').lines.first"
+    - name: gcc and ridk version (mingw)
+      if: startsWith(matrix.os, 'windows')
+      run: |
+        $abi, $plat = $(ruby -e "STDOUT.write RbConfig::CONFIG['ruby_version'] + ' ' + RUBY_PLATFORM").split(' ')
+        if ($plat.Contains('mingw')) {
+          gcc --version
+          if ($abi -ge '2.4') {
+            ridk version
+          } else {
+            echo 'ridk is unavailable'
+          }
+        }
+    - name: RbConfig::CONFIG
+      run: ruby -rrbconfig -rpp -e 'pp RbConfig::CONFIG'
+    - name: RbConfig::MAKEFILE_CONFIG
+      run: ruby -rrbconfig -rpp -e 'pp RbConfig::MAKEFILE_CONFIG'
+
+    - name: Subprocess test
+      run: ruby test_subprocess.rb
+    - name: OpenSSL version
+      run: ruby -ropenssl -e 'puts OpenSSL::OPENSSL_LIBRARY_VERSION'
+    - name: OpenSSL test
+      run: ruby -ropen-uri -e 'puts URI.send(:open, %{https://rubygems.org/}) { |f| f.read(1024) }'
+
+    - name: C extension test
+      run: gem install json:2.2.0 --no-document
+    - run: bundle --version
+    # This step is redundant with `bundler-cache: true` but is there to check a redundant `bundle install` still works
+    - run: bundle install
+    - run: bundle exec rake --version
+
+    - name: which ruby, rake
+      if: "!startsWith(matrix.os, 'windows')"
+      run: which -a ruby rake
+    - name: where ruby, rake
+      if: startsWith(matrix.os, 'windows')
+      run: |
+        $ErrorActionPreference = 'Continue'
+        $where = 'ruby', 'rake'
+        foreach ($e in $where) {
+          $rslt = where.exe $e 2>&1 | Out-String
+          if ($rslt.contains($e)) { echo $rslt.Trim() }
+          else { echo "Can't find $e" }
+          echo ''
+        }
+    - name: bash test
+      shell: bash
+      run: echo ~
+    # Disabled until https://github.com/jruby/jruby/issues/6648 is fixed
+    # - name: Windows JRuby
+    #   if: startsWith(matrix.os, 'windows') && startsWith(matrix.ruby, 'jruby')
+    #   run: gem install sassc -N
+
+  testExactBundlerVersion:
+    name: "Test with an exact Bundler version"
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
     - uses: ./
       with:
-        ruby-version: ${{ matrix.ruby }}
-    - run: ruby --version
-    - run: ridk version
-      if: matrix.os == 'windows-latest' && !startsWith(matrix.ruby, '2.3')
-    - name: OpenSSL version
-      run: ruby -ropenssl -e 'puts OpenSSL::OPENSSL_LIBRARY_VERSION'
-    - name: OpenSSL test
-      run: ruby -ropen-uri -e 'puts open(%{https://rubygems.org/}) { |f| f.read(1024) }'
-    - name: C extension test
-      run: gem install json:2.2.0 --no-document
-    - run: bundle --version
-    - run: bundle install
-    - run: bundle exec rake --version
+        ruby-version: 2.6
+        bundler: 2.2.3
+    - run: bundle --version | grep -F "Bundler version 2.2.3"
+
+  testDependencyOnBundler1:
+    name: "Test gemfile depending on Bundler 1"
+    runs-on: ubuntu-latest
+    env:
+      BUNDLE_GEMFILE: gemfiles/bundler1.gemfile
+    steps:
+      - uses: actions/checkout@v2
+      - uses: ./
+        with:
+          ruby-version: 2.7
+          bundler: 1
+          bundler-cache: true
+      - run: bundle --version | grep -F "Bundler version 1."
+
+  testGemfileMatrix:
+    strategy:
+      fail-fast: false
+      matrix:
+        gemfile: [ rails5, rails6 ]
+    name: "Test with ${{ matrix.gemfile }} gemfile"
+    runs-on: ubuntu-latest
+    env:
+      BUNDLE_GEMFILE: gemfiles/${{ matrix.gemfile }}.gemfile
+    steps:
+      - uses: actions/checkout@v2
+      - uses: ./
+        with:
+          ruby-version: 2.6
+          bundler-cache: true
+      - run: bundle exec rails --version
+
+  testTruffleRubyNokogiri:
+    name: "Test installing a Gemfile with nokogiri on TruffleRuby"
+    runs-on: ubuntu-latest
+    env:
+      BUNDLE_GEMFILE: gemfiles/nokogiri.gemfile
+    steps:
+      - uses: actions/checkout@v2
+      - uses: ./
+        with:
+          ruby-version: truffleruby-head
+          bundler-cache: true
+      - run: bundle list | grep nokogiri
 
   lint:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
     - uses: actions/checkout@v2
     - run: yarn install
-    - run: yarn run lint
+    - run: yarn run package
+    - name: Check generated files are up to date
+      run: git diff --exit-code

.tool-versions

@@ -0,0 +1,2 @@
+nodejs 12.0.0
+ruby 2.7.0

CONTRIBUTING.md

@@ -0,0 +1,21 @@
+# Contributing
+
+## Installing dependencies
+
+```bash
+$ yarn install
+```
+
+`npm` doesn't install the correct dependencies for `eslint` so we use `yarn`.
+
+## Regenerating dist/index.js
+
+```bash
+$ yarn run package
+```
+
+It is recommended to add this as a `git` `pre-commit` hook:
+
+```bash
+$ cp pre-commit .git/hooks/pre-commit
+```

README.md

@@ -1,40 +1,54 @@
-# use-ruby-action
+# setup-ruby
 
 This action downloads a prebuilt ruby and adds it to the `PATH`.
 
 It is very efficient and takes about 5 seconds to download, extract and add the given Ruby to the `PATH`.
 No extra packages need to be installed.
 
+Compared to [actions/setup-ruby](https://github.com/actions/setup-ruby),
+this actions supports many more versions and features.
+
 ### Supported Versions
 
 This action currently supports these versions of MRI, JRuby and TruffleRuby:
 
 | Interpreter | Versions |
 | ----------- | -------- |
-| Ruby | 2.3.0 - 2.3.8, 2.4.0 - 2.4.9, 2.5.0 - 2.5.7, 2.6.0 - 2.6.5, 2.7.0 |
-| JRuby | 9.2.9.0 |
-| TruffleRuby | 19.3.0, 19.3.1, head |
-| Rubinius | 4.13 |
+| `ruby` | 2.1.9, 2.2, all versions from 2.3.0 until 3.0.1, head, debug, mingw, mswin |
+| `jruby` | 9.1.17.0, 9.2.9.0 - 9.2.17.0, head |
+| `truffleruby` | 19.3.0 - 21.1.0, head |
 
-Note that Ruby 2.3 and the OpenSSL version it needs (1.0.2) are both end-of-life,
-which means Ruby 2.3 is unmaintained and considered insecure.
-On Windows, Ruby 2.4 uses OpenSSL 1.0.2, which is no longer maintained.
+`ruby-debug` is the same as `ruby-head` but with assertions enabled (`-DRUBY_DEBUG=1`).  
+On Windows, `mingw` and `mswin` are `ruby-head` builds using the MSYS2/MinGW and the MSVC toolchains respectively.
+
+Preview and RC versions of Ruby might be available too on Ubuntu and macOS (not on Windows).
+However, it is recommended to test against `ruby-head` rather than previews,
+as it provides more useful feedback for the Ruby core team and for upcoming changes.
+
+Only versions published by [RubyInstaller](https://rubyinstaller.org/downloads/archives/) are available on Windows.
+Due to that, Ruby 2.2 resolves to 2.2.6 on Windows and 2.2.10 on other platforms.
+And Ruby 2.3 on Windows only has builds for 2.3.0, 2.3.1 and 2.3.3.
+
+Note that Ruby ≤ 2.4 and the OpenSSL version it needs (1.0.2) are both end-of-life,
+which means Ruby ≤ 2.4 is unmaintained and considered insecure.
 
 ### Supported Platforms
 
 The action works for all [GitHub-hosted runners](https://help.github.com/en/actions/automating-your-workflow-with-github-actions/virtual-environments-for-github-hosted-runners).
 
-| Operating System | Versions |
-| ----------- | -------- |
-| Ubuntu  | `ubuntu-latest` (= `ubuntu-18.04`), `ubuntu-16.04` |
-| macOS   | `macos-latest` |
-| Windows | `windows-latest` |
+| Operating System | Recommended | Other Supported Versions |
+| ----------- | -------- | -------- |
+| Ubuntu  | `ubuntu-latest`  (= `ubuntu-20.04`) | `ubuntu-18.04`, `ubuntu-16.04` |
+| macOS   | `macos-latest`   (= `macos-10.15`)  | `macos-11.0` |
+| Windows | `windows-latest` (= `windows-2019`) | `windows-2016` |
 
-Rubinius is only available on `ubuntu-latest`.
-
-The prebuilt rubies are generated by [eregon/ruby-install-builder](https://github.com/eregon/ruby-install-builder)
-and on Windows by [RubyInstaller2](https://github.com/oneclick/rubyinstaller2).  
-The full list of available Ruby versions can be seen in [ruby-install-builder-versions.js](ruby-install-builder-versions.js)
+The prebuilt releases are generated by [ruby-builder](https://github.com/ruby/ruby-builder)
+and on Windows by [RubyInstaller2](https://github.com/oneclick/rubyinstaller2).
+`mingw` and `mswin` builds are generated by [ruby-loco](https://github.com/MSP-Greg/ruby-loco).
+`ruby-head` is generated by [ruby-dev-builder](https://github.com/ruby/ruby-dev-builder),
+`jruby-head` is generated by [jruby-dev-builder](https://github.com/ruby/jruby-dev-builder)
+and `truffleruby-head` is generated by [truffleruby-dev-builder](https://github.com/ruby/truffleruby-dev-builder).
+The full list of available Ruby versions can be seen in [ruby-builder-versions.js](ruby-builder-versions.js)
 for Ubuntu and macOS and in [windows-versions.js](windows-versions.js) for Windows.
 
 ## Usage
@@ -43,89 +57,196 @@ for Ubuntu and macOS and in [windows-versions.js](windows-versions.js) for Windo
 
 ```yaml
 name: My workflow
-on: [push]
+on: [push, pull_request]
 jobs:
   test:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
-    - uses: eregon/use-ruby-action@v1
+    - uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 2.6
-    - run: ruby -v
+        ruby-version: 2.6 # Not needed with a .ruby-version file
+        bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+    - run: bundle exec rake
 ```
 
-### Matrix
+### Matrix of Ruby Versions
 
-This matrix tests all stable releases of MRI, JRuby and TruffleRuby on Ubuntu and macOS.
+This matrix tests all stable releases and `head` versions of MRI, JRuby and TruffleRuby on Ubuntu and macOS.
 
 ```yaml
 name: My workflow
-on: [push]
+on: [push, pull_request]
 jobs:
   test:
     strategy:
       fail-fast: false
       matrix:
-        os: [ ubuntu-latest, macos-latest ]
-        ruby: [ 2.4, 2.5, 2.6, 2.7, jruby, truffleruby ]
+        os: [ubuntu-latest, macos-latest]
+        # Due to https://github.com/actions/runner/issues/849, we have to use quotes for '3.0'
+        ruby: [2.5, 2.6, 2.7, '3.0', head, jruby, jruby-head, truffleruby, truffleruby-head]
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v2
-    - uses: eregon/use-ruby-action@v1
+    - uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby }}
-    - run: ruby -v
+        bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+    - run: bundle exec rake
 ```
 
+### Matrix of Gemfiles
+
+```yaml
+name: My workflow
+on: [push, pull_request]
+jobs:
+  test:
+    strategy:
+      fail-fast: false
+      matrix:
+        gemfile: [ rails5, rails6 ]
+    runs-on: ubuntu-latest
+    env: # $BUNDLE_GEMFILE must be set at the job level, so it is set for all steps
+      BUNDLE_GEMFILE: gemfiles/${{ matrix.gemfile }}.gemfile
+    steps:
+      - uses: actions/checkout@v2
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: 2.6
+          bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+      - run: bundle exec rake
+```
+
+See the GitHub Actions documentation for more details about the
+[workflow syntax](https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions)
+and the [condition and expression syntax](https://help.github.com/en/actions/reference/context-and-expression-syntax-for-github-actions).
+
 ### 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
-* `.ruby-version` (also the default value) reads from the project's `.ruby-version` file
+* `.ruby-version` reads from the project's `.ruby-version` file
+* `.tool-versions` reads from the project's `.tool-versions` file
+* If the `ruby-version` input is not specified, `.ruby-version` is tried first, followed by `.tool-versions`
+
+### Working Directory
+
+The `working-directory` input can be set to resolve `.ruby-version`, `.tool-versions` and `Gemfile.lock`
+if they are not at the root of the repository, see [action.yml](action.yml) for details.
 
 ### Bundler
 
-Currently, Bundler is guaranteed to be installed for all versions.
-If the Ruby ships with Bundler (Ruby >= 2.6), that version is used.
-Otherwise (Ruby < 2.6), Bundler 1 is installed when that Ruby was built.
+By default, if there is a `Gemfile.lock` file (or `$BUNDLE_GEMFILE.lock` or `gems.locked`) with a `BUNDLED WITH` section,
+that version of Bundler will be installed and used.
+Otherwise, the latest compatible Bundler version is installed (Bundler 2 on Ruby >= 2.4, Bundler 1 on Ruby < 2.4).
 
-### Caching `bundle install`
+This behavior can be customized, see [action.yml](action.yml) for more details about the `bundler` input.
 
-You can cache the installed gems with these two steps:
+### Caching `bundle install` automatically
 
+This action provides a way to automatically run `bundle install` and cache the result:
 ```yaml
-    - uses: actions/cache@v1
+    - uses: ruby/setup-ruby@v1
       with:
-        path: vendor/bundle
-        key: bundle-use-ruby-${{ matrix.os }}-${{ matrix.ruby }}-${{ hashFiles('**/Gemfile.lock') }}
-        restore-keys: |
-          bundle-use-ruby-${{ matrix.os }}-${{ matrix.ruby }}-
-    - name: bundle install
-      run: |
-        bundle config path vendor/bundle
-        bundle install --jobs 4 --retry 3
+        bundler-cache: true
 ```
 
-When using a single job with a Ruby version, replace `${{ matrix.ruby }}` with the Ruby version.  
-When using `.ruby-version`, replace `${{ matrix.ruby }}` with `${{ hashFiles('.ruby-version') }}`.
+Note that any step doing `bundle install` (for the root `Gemfile`) or `gem install bundler` can be removed with `bundler-cache: true`.
 
-This uses the [cache action](https://github.com/actions/cache).
-The code above is a more complete version of the [Ruby - Bundler example](https://github.com/actions/cache/blob/master/examples.md#ruby---bundler).
-Make sure to include `use-ruby` in the `key` to avoid conflicting with previous caches.
+This caching speeds up installing gems significantly and avoids too many requests to RubyGems.org.  
+It needs a `Gemfile` (or `$BUNDLE_GEMFILE` or `gems.rb`) under the [`working-directory`](#working-directory).  
+If there is a `Gemfile.lock` (or `$BUNDLE_GEMFILE.lock` or `gems.locked`), `bundle config --local deployment true` is used.
 
-## Limitations
+To use a `Gemfile` which is not at the root or has a different name, set `BUNDLE_GEMFILE` in the `env` at the job level
+as shown in the [example](#matrix-of-gemfiles).
 
-* This action currently only works with GitHub-hosted runners, not private runners.
+#### bundle config
+
+When using `bundler-cache: true` you might notice there is no good place to run `bundle config ...` commands.
+These can be replaced by `BUNDLE_*` environment variables, which are also faster.
+They should be set in the `env` at the job level as shown in the [example](#matrix-of-gemfiles).
+To find the correct the environment variable name, see the [Bundler docs](https://bundler.io/man/bundle-config.1.html) or look at `.bundle/config` after running `bundle config --local KEY VALUE` locally.
+You might need to `"`-quote the environment variable name in YAML if it has unusual characters like `/`.
+
+To perform caching, this action will use `bundle config --local path $PWD/vendor/bundle`.  
+Therefore, the Bundler `path` should not be changed in your workflow for the cache to work (no `bundle config path`).
+
+#### How it Works
+
+When there is no lockfile, one is generated with `bundle lock`, which is the same as `bundle install` would do first before actually fetching any gem.
+In other words, it works exactly like `bundle install`.
+The hash of the generated lockfile is then used for caching, which is the only correct approach.
+
+#### Dealing with a corrupted cache
+
+In some rare scenarios (like using gems with C extensions whose functionality depends on libraries found on the system
+at the time of the gem's build) it may be necessary to ignore contents of the cache and get and build all the gems anew.
+In order to achieve this, set the `cache-version` option to any value other than `0` (or change it to a new unique value
+if you have already used it before.)
+
+```yaml
+    - uses: ruby/setup-ruby@v1
+      with:
+        bundler-cache: true
+        cache-version: 1
+```
+
+#### Caching `bundle install` manually
+
+It is also possible to cache gems manually, but this is not recommended because it is verbose and *very difficult* to do correctly.
+There are many concerns which means using `actions/cache` is never enough for caching gems (e.g., incomplete cache key, cleaning old gems when restoring from another key, correctly hashing the lockfile if not checked in, OS versions, ABI compatibility for `ruby-head`, etc).
+So, please use `bundler-cache: true` instead and report any issue.
+
+## Windows
+
+Note that running CI on Windows can be quite challenging if you are not very familiar with Windows.
+It is recommended to first get your build working on Ubuntu and macOS before trying Windows.
+
+* The default shell on Windows is not Bash but [PowerShell](https://help.github.com/en/actions/automating-your-workflow-with-github-actions/workflow-syntax-for-github-actions#using-a-specific-shell).
+  This can lead issues such as multi-line scripts [not working as expected](https://github.com/ruby/setup-ruby/issues/13).
+* The `PATH` contains [multiple compiler toolchains](https://github.com/ruby/setup-ruby/issues/19). Use `where.exe` to debug which tool is used.
+* For Ruby ≥ 2.4, MSYS2 is prepended to the `Path`, similar to what RubyInstaller2 does.
+* For Ruby < 2.4, the DevKit MSYS tools are installed and prepended to the `Path`.
+* JRuby on Windows has a known bug that `bundle exec rake` [fails](https://github.com/ruby/setup-ruby/issues/18).
 
 ## Versioning
 
+It is highly recommended to use `ruby/setup-ruby@v1` for the version of this action.
+This will provide the best experience by automatically getting bug fixes, new Ruby versions and new features.
+
+If you instead choose a specific version (v1.2.3) or a commit sha, there will be no automatic bug fixes and
+it will be your responsibility to update every time the action no longer works.
+Make sure to always use the latest release before reporting an issue on GitHub.
+
 This action follows semantic versioning with a moving `v1` branch.
 This follows the [recommendations](https://github.com/actions/toolkit/blob/master/docs/action-versioning.md) of GitHub Actions.
 
+## Using self-hosted runners
+
+This action might work with [self-hosted runners](https://docs.github.com/en/actions/hosting-your-own-runners/about-self-hosted-runners)
+if the [virtual environment](https://github.com/actions/virtual-environments) is very similar to the ones used by GitHub runners. Notably:
+
+* Make sure to use the same operating system and version.
+* Set the environment variable `ImageOS` on the runner to the corresponding value on GitHub-hosted runners (e.g. `ubuntu18`/`macos1015`/`win19`). This is necessary to detect the operating system and version.
+* Make sure to use the same version of libssl.
+* Make sure that the operating system has `libyaml-0` installed
+* The default tool cache directory (`/opt/hostedtoolcache` on Linux, `/Users/runner/hostedtoolcache` on macOS,
+  `C:/hostedtoolcache/windows` on Windows) must be writable by the `runner` user.
+  This is necessary since the Ruby builds embed the install path when built and cannot be moved around.
+* `/home/runner` must be writable by the `runner` user.
+
+In other cases, please use a system Ruby or [install Ruby manually](https://github.com/postmodern/chruby/wiki#installing-rubies) instead.
+
+## History
+
+This action used to be at `eregon/use-ruby-action` and was moved to the `ruby` organization.
+Please [update](https://github.com/ruby/setup-ruby/releases/tag/v1.13.0) if you are using `eregon/use-ruby-action`.
+
 ## Credits
 
-Most of the Windows logic is from https://github.com/MSP-Greg/actions-ruby by MSP-Greg.
+The current maintainer of this action is @eregon.
+Most of the Windows logic is based on work by MSP-Greg.
 Many thanks to MSP-Greg and Lars Kanis for the help with Ruby Installer.

action.yml

@@ -6,9 +6,30 @@ branding:
   icon: download
 inputs:
   ruby-version:
-    description: 'Engine and version to use, see the syntax in the README. Reads from .ruby-version if unset.'
+    description: 'Engine and version to use, see the syntax in the README. Reads from .ruby-version or .tool-versions if unset.'
     required: false
-    default: '.ruby-version'
+    default: 'default'
+  bundler:
+    description: |
+      The version of Bundler to install. Either 'none', 'latest', 'Gemfile.lock', or a version number (e.g., 1, 2, 2.1.4).
+      For 'Gemfile.lock', the version is determined based on the BUNDLED WITH section from the file Gemfile.lock, $BUNDLE_GEMFILE.lock or gems.locked.
+      Defaults to 'Gemfile.lock' if the file exists and 'latest' otherwise.
+    required: false
+    default: 'default'
+  bundler-cache:
+    description: 'Run "bundle install", and cache the result automatically. Either true or false.'
+    required: false
+    default: 'false'
+  working-directory:
+    description: 'The working directory to use for resolving paths for .ruby-version, .tool-versions and Gemfile.lock.'
+    required: false
+    default: '.'
+  cache-version:
+    description: |
+      Arbitrary string that will be added to the cache key of the bundler cache. Set or change it if you need
+      to invalidate the cache.
+    required: false
+    default: '0'
 outputs:
   ruby-prefix:
     description: 'The prefix of the installed ruby'

bundler.js

@@ -0,0 +1,201 @@
+const fs = require('fs')
+const path = require('path')
+const core = require('@actions/core')
+const exec = require('@actions/exec')
+const cache = require('@actions/cache')
+const common = require('./common')
+
+export const DEFAULT_CACHE_VERSION = '0'
+
+// The returned gemfile is guaranteed to exist, the lockfile might not exist
+export function detectGemfiles() {
+  const gemfilePath = process.env['BUNDLE_GEMFILE'] || 'Gemfile'
+  if (fs.existsSync(gemfilePath)) {
+    return [gemfilePath, `${gemfilePath}.lock`]
+  } else if (process.env['BUNDLE_GEMFILE']) {
+    throw new Error(`$BUNDLE_GEMFILE is set to ${gemfilePath} but does not exist`)
+  }
+
+  if (fs.existsSync("gems.rb")) {
+    return ["gems.rb", "gems.locked"]
+  }
+
+  return [null, null]
+}
+
+function readBundledWithFromGemfileLock(lockFile) {
+  if (lockFile !== null && fs.existsSync(lockFile)) {
+    const contents = fs.readFileSync(lockFile, 'utf8')
+    const lines = contents.split(/\r?\n/)
+    const bundledWithLine = lines.findIndex(line => /^BUNDLED WITH$/.test(line.trim()))
+    if (bundledWithLine !== -1) {
+      const nextLine = lines[bundledWithLine+1]
+      if (nextLine && /^\d+/.test(nextLine.trim())) {
+        const bundlerVersion = nextLine.trim()
+        console.log(`Using Bundler ${bundlerVersion} from ${lockFile} BUNDLED WITH ${bundlerVersion}`)
+        return bundlerVersion
+      }
+    }
+  }
+  return null
+}
+
+async function afterLockFile(lockFile, platform, engine) {
+  if (engine === 'truffleruby' && platform.startsWith('ubuntu-')) {
+    const contents = fs.readFileSync(lockFile, 'utf8')
+    if (contents.includes('nokogiri')) {
+      await common.measure('Installing libxml2-dev libxslt-dev, required to install nokogiri on TruffleRuby', async () =>
+          exec.exec('sudo', ['apt-get', '-yqq', 'install', 'libxml2-dev', 'libxslt-dev'], { silent: true }))
+    }
+  }
+}
+
+export async function installBundler(bundlerVersionInput, lockFile, platform, rubyPrefix, engine, rubyVersion) {
+  let bundlerVersion = bundlerVersionInput
+
+  if (bundlerVersion === 'default' || bundlerVersion === 'Gemfile.lock') {
+    bundlerVersion = readBundledWithFromGemfileLock(lockFile)
+
+    if (!bundlerVersion) {
+      bundlerVersion = 'latest'
+    }
+  }
+
+  if (bundlerVersion === 'latest') {
+    bundlerVersion = '2'
+  }
+
+  if (/^\d+/.test(bundlerVersion)) {
+    // OK
+  } else {
+    throw new Error(`Cannot parse bundler input: ${bundlerVersion}`)
+  }
+
+  if (engine === 'ruby' && rubyVersion.match(/^2\.[012]/)) {
+    console.log('Bundler 2 requires Ruby 2.3+, using Bundler 1 on Ruby <= 2.2')
+    bundlerVersion = '1'
+  } else if (engine === 'ruby' && rubyVersion.match(/^2\.3\.[01]/)) {
+    console.log('Ruby 2.3.0 and 2.3.1 have shipped with an old rubygems that only works with Bundler 1')
+    bundlerVersion = '1'
+  } else if (engine === 'jruby' && rubyVersion.startsWith('9.1')) { // JRuby 9.1 targets Ruby 2.3, treat it the same
+    console.log('JRuby 9.1 has a bug with Bundler 2 (https://github.com/ruby/setup-ruby/issues/108), using Bundler 1 instead on JRuby 9.1')
+    bundlerVersion = '1'
+  }
+
+  if (common.isHeadVersion(rubyVersion) && common.isBundler2Default(engine, rubyVersion) && bundlerVersion.startsWith('2')) {
+    // Avoid installing a newer Bundler version for head versions as it might not work.
+    // For releases, even if they ship with Bundler 2 we install the latest Bundler.
+    console.log(`Using Bundler 2 shipped with ${engine}-${rubyVersion}`)
+  } else if (engine === 'truffleruby' && !common.isHeadVersion(rubyVersion) && bundlerVersion.startsWith('1')) {
+    console.log(`Using Bundler 1 shipped with ${engine}`)
+  } else {
+    const gem = path.join(rubyPrefix, 'bin', 'gem')
+    const bundlerVersionConstraint = bundlerVersion.match(/^\d+\.\d+\.\d+/) ? bundlerVersion : `~> ${bundlerVersion}`
+    await exec.exec(gem, ['install', 'bundler', '-v', bundlerVersionConstraint, '--no-document'])
+  }
+
+  return bundlerVersion
+}
+
+export async function bundleInstall(gemfile, lockFile, platform, engine, rubyVersion, bundlerVersion, cacheVersion) {
+  if (gemfile === null) {
+    console.log('Could not determine gemfile path, skipping "bundle install" and caching')
+    return false
+  }
+
+  let envOptions = {}
+  if (bundlerVersion.startsWith('1') && common.isBundler2Default(engine, rubyVersion)) {
+    // If Bundler 1 is specified on Rubies which ship with Bundler 2,
+    // we need to specify which Bundler version to use explicitly until the lockfile exists.
+    console.log(`Setting BUNDLER_VERSION=${bundlerVersion} for "bundle config|lock" commands below to ensure Bundler 1 is used`)
+    envOptions = { env: { ...process.env, BUNDLER_VERSION: bundlerVersion } }
+  }
+
+  // config
+  const cachePath = 'vendor/bundle'
+  // An absolute path, so it is reliably under $PWD/vendor/bundle, and not relative to the gemfile's directory
+  const bundleCachePath = path.join(process.cwd(), cachePath)
+
+  await exec.exec('bundle', ['config', '--local', 'path', bundleCachePath], envOptions)
+
+  if (fs.existsSync(lockFile)) {
+    await exec.exec('bundle', ['config', '--local', 'deployment', 'true'], envOptions)
+  } else {
+    // Generate the lockfile so we can use it to compute the cache key.
+    // This will also automatically pick up the latest gem versions compatible with the Gemfile.
+    await exec.exec('bundle', ['lock'], envOptions)
+  }
+
+  await afterLockFile(lockFile, platform, engine)
+
+  // cache key
+  const paths = [cachePath]
+  const baseKey = await computeBaseKey(platform, engine, rubyVersion, lockFile, cacheVersion)
+  const key = `${baseKey}-${await common.hashFile(lockFile)}`
+  // If only Gemfile.lock changes we can reuse part of the cache, and clean old gem versions below
+  const restoreKeys = [`${baseKey}-`]
+  console.log(`Cache key: ${key}`)
+
+  // restore cache & install
+  let cachedKey = null
+  try {
+    cachedKey = await cache.restoreCache(paths, key, restoreKeys)
+  } catch (error) {
+    if (error.name === cache.ValidationError.name) {
+      throw error;
+    } else {
+      core.info(`[warning] There was an error restoring the cache ${error.message}`)
+    }
+  }
+
+  if (cachedKey) {
+    console.log(`Found cache for key: ${cachedKey}`)
+  }
+
+  // Always run 'bundle install' to list the gems
+  await exec.exec('bundle', ['install', '--jobs', '4'])
+
+  // @actions/cache only allows to save for non-existing keys
+  if (cachedKey !== key) {
+    if (cachedKey) { // existing cache but Gemfile.lock differs, clean old gems
+      await exec.exec('bundle', ['clean'])
+    }
+
+    // Error handling from https://github.com/actions/cache/blob/master/src/save.ts
+    console.log('Saving cache')
+    try {
+      await cache.saveCache(paths, key)
+    } catch (error) {
+      if (error.name === cache.ValidationError.name) {
+        throw error;
+      } else if (error.name === cache.ReserveCacheError.name) {
+        core.info(error.message);
+      } else {
+        core.info(`[warning]${error.message}`)
+      }
+    }
+  }
+
+  return true
+}
+
+async function computeBaseKey(platform, engine, version, lockFile, cacheVersion) {
+  const cacheVersionSuffix = DEFAULT_CACHE_VERSION === cacheVersion ? '' : `-cachever:${cacheVersion}`
+  let key = `setup-ruby-bundler-cache-v3-${platform}-${engine}-${version}${cacheVersionSuffix}`
+
+  if (engine !== 'jruby' && common.isHeadVersion(version)) {
+    let revision = '';
+    await exec.exec('ruby', ['-e', 'print RUBY_REVISION'], {
+      silent: true,
+      listeners: {
+        stdout: (data) => {
+          revision += data.toString();
+        }
+      }
+    });
+    key += `-revision-${revision}`
+  }
+
+  key += `-${lockFile}`
+  return key
+}

common.js

@@ -0,0 +1,180 @@
+const os = require('os')
+const path = require('path')
+const fs = require('fs')
+const util = require('util')
+const stream = require('stream')
+const crypto = require('crypto')
+const core = require('@actions/core')
+const { performance } = require('perf_hooks')
+
+export const windows = (os.platform() === 'win32')
+// Extract to SSD on Windows, see https://github.com/ruby/setup-ruby/pull/14
+export const drive = (windows ? (process.env['GITHUB_WORKSPACE'] || 'C')[0] : undefined)
+
+export function partition(string, separator) {
+  const i = string.indexOf(separator)
+  if (i === -1) {
+    throw new Error(`No separator ${separator} in string ${string}`)
+  }
+  return [string.slice(0, i), string.slice(i + separator.length, string.length)]
+}
+
+let inGroup = false
+
+export async function measure(name, block) {
+  const body = async () => {
+    const start = performance.now()
+    try {
+      return await block()
+    } finally {
+      const end = performance.now()
+      const duration = (end - start) / 1000.0
+      console.log(`Took ${duration.toFixed(2).padStart(6)} seconds`)
+    }
+  }
+
+  if (inGroup) {
+    // Nested groups are not yet supported on GitHub Actions
+    console.log(`> ${name}`)
+    return await body()
+  } else {
+    inGroup = true
+    try {
+      return await core.group(name, body)
+    } finally {
+      inGroup = false
+    }
+  }
+}
+
+export function isHeadVersion(rubyVersion) {
+  return rubyVersion === 'head' || rubyVersion === 'debug' || rubyVersion === 'mingw' || rubyVersion === 'mswin'
+}
+
+export function isStableVersion(rubyVersion) {
+  return /^\d+(\.\d+)*$/.test(rubyVersion)
+}
+
+export function isBundler2Default(engine, rubyVersion) {
+  if (engine === 'ruby') {
+    return isHeadVersion(rubyVersion) || floatVersion(rubyVersion) >= 2.7
+  } else if (engine === 'truffleruby') {
+    return isHeadVersion(rubyVersion) || floatVersion(rubyVersion) >= 21.0
+  } else if (engine === 'jruby') {
+    return isHeadVersion(rubyVersion) || floatVersion(rubyVersion) >= 9.3
+  } else {
+    return false
+  }
+}
+
+export function floatVersion(rubyVersion) {
+  const match = rubyVersion.match(/^\d+\.\d+/)
+  if (match) {
+    return parseFloat(match[0])
+  } else {
+    return 0.0
+  }
+}
+
+export async function hashFile(file) {
+  // See https://github.com/actions/runner/blob/master/src/Misc/expressionFunc/hashFiles/src/hashFiles.ts
+  const hash = crypto.createHash('sha256')
+  const pipeline = util.promisify(stream.pipeline)
+  await pipeline(fs.createReadStream(file), hash)
+  return hash.digest('hex')
+}
+
+function getImageOS() {
+  const imageOS = process.env['ImageOS']
+  if (!imageOS) {
+    throw new Error('The environment variable ImageOS must be set')
+  }
+  return imageOS
+}
+
+export function getVirtualEnvironmentName() {
+  const imageOS = getImageOS()
+
+  let match = imageOS.match(/^ubuntu(\d+)/) // e.g. ubuntu18
+  if (match) {
+    return `ubuntu-${match[1]}.04`
+  }
+
+  match = imageOS.match(/^macos(\d{2})(\d+)?/) // e.g. macos1015, macos11
+  if (match) {
+    return `macos-${match[1]}.${match[2] || '0'}`
+  }
+
+  match = imageOS.match(/^win(\d+)/) // e.g. win19
+  if (match) {
+    return `windows-20${match[1]}`
+  }
+
+  throw new Error(`Unknown ImageOS ${imageOS}`)
+}
+
+export function shouldUseToolCache(engine, version) {
+  return engine === 'ruby' && !isHeadVersion(version)
+}
+
+function getPlatformToolCache(platform) {
+  // Hardcode paths rather than using $RUNNER_TOOL_CACHE because the prebuilt Rubies cannot be moved anyway
+  if (platform.startsWith('ubuntu-')) {
+    return '/opt/hostedtoolcache'
+  } else if (platform.startsWith('macos-')) {
+    return '/Users/runner/hostedtoolcache'
+  } else if (platform.startsWith('windows-')) {
+    return 'C:/hostedtoolcache/windows'
+  } else {
+    throw new Error('Unknown platform')
+  }
+}
+
+export function getToolCacheRubyPrefix(platform, version) {
+  const toolCache = getPlatformToolCache(platform)
+  return path.join(toolCache, 'Ruby', version, 'x64')
+}
+
+export function createToolCacheCompleteFile(toolCacheRubyPrefix) {
+  const completeFile = `${toolCacheRubyPrefix}.complete`
+  fs.writeFileSync(completeFile, '')
+}
+
+// convert windows path like C:\Users\runneradmin to /c/Users/runneradmin
+export function win2nix(path) {
+  if (/^[A-Z]:/i.test(path)) {
+    // path starts with drive
+    path = `/${path[0].toLowerCase()}${partition(path, ':')[1]}`
+  }
+  return path.replace(/\\/g, '/').replace(/ /g, '\\ ')
+}
+
+export function setupPath(newPathEntries) {
+  const envPath = windows ? 'Path' : 'PATH'
+  const originalPath = process.env[envPath].split(path.delimiter)
+  let cleanPath = originalPath.filter(entry => !/\bruby\b/i.test(entry))
+
+  // First remove the conflicting path entries
+  if (cleanPath.length !== originalPath.length) {
+    core.startGroup(`Cleaning ${envPath}`)
+    console.log(`Entries removed from ${envPath} to avoid conflicts with Ruby:`)
+    for (const entry of originalPath) {
+      if (!cleanPath.includes(entry)) {
+        console.log(`  ${entry}`)
+      }
+    }
+    core.exportVariable(envPath, cleanPath.join(path.delimiter))
+    core.endGroup()
+  }
+
+  // Then add new path entries using core.addPath()
+  let newPath
+  if (windows) {
+    // add MSYS2 in path for all Rubies on Windows, as it provides a better bash shell and a native toolchain
+    const msys2 = ['C:\\msys64\\mingw64\\bin', 'C:\\msys64\\usr\\bin']
+    newPath = [...newPathEntries, ...msys2]
+  } else {
+    newPath = newPathEntries
+  }
+  core.addPath(newPath.join(path.delimiter))
+}

gemfiles/bundler1.gemfile

@@ -0,0 +1,3 @@
+source 'https://rubygems.org'
+
+gem "bundler", "~> 1.0"

gemfiles/nokogiri.gemfile

@@ -0,0 +1,3 @@
+source "https://rubygems.org"
+
+gem "nokogiri"

gemfiles/rails5.gemfile

@@ -0,0 +1,3 @@
+source "https://rubygems.org"
+
+gem "rails", "~> 5.2.0"

gemfiles/rails6.gemfile

@@ -0,0 +1,3 @@
+source "https://rubygems.org"
+
+gem "rails", "~> 6.0.0"

generate-windows-versions.rb

@@ -2,6 +2,8 @@ require 'net/http'
 require 'yaml'
 require 'json'
 
+min_requirements = ['~> 2.1.9', '>= 2.2.6'].map { |req| Gem::Requirement.new(req) }
+
 url = 'https://raw.githubusercontent.com/oneclick/rubyinstaller.org-website/master/_data/downloads.yaml'
 entries = YAML.load(Net::HTTP.get(URI(url)), symbolize_names: true)
 
@@ -16,12 +18,16 @@ versions = entries.select { |entry|
   end
   [version, builds.first]
 }.sort_by { |version, entry|
-  version
+  Gem::Version.new(version)
 }.select { |version, entry|
-  version >= "2.3"
+  min_requirements.any? { |req| req.satisfied_by?(Gem::Version.new(version)) }
 }.map { |version, entry|
   [version, entry[:href]]
 }.to_h
 
+versions['head'] = 'https://github.com/oneclick/rubyinstaller2/releases/download/rubyinstaller-head/rubyinstaller-head-x64.7z'
+versions['mingw'] = 'https://github.com/MSP-Greg/ruby-loco/releases/download/ruby-master/ruby-mingw.7z'
+versions['mswin'] = 'https://github.com/MSP-Greg/ruby-loco/releases/download/ruby-master/ruby-mswin.7z'
+
 js = "export const versions = #{JSON.pretty_generate(versions)}\n"
-File.write 'windows-versions.js', js
+File.binwrite 'windows-versions.js', js

index.js

@@ -1,90 +1,162 @@
 const os = require('os')
 const fs = require('fs')
+const path = require('path')
 const core = require('@actions/core')
+const common = require('./common')
+const bundler = require('./bundler')
 
-async function run() {
+const windows = common.windows
+
+const inputDefaults = {
+  'ruby-version': 'default',
+  'bundler': 'default',
+  'bundler-cache': 'true',
+  'working-directory': '.',
+  'cache-version': bundler.DEFAULT_CACHE_VERSION,
+}
+
+// entry point when this action is run on its own
+export async function run() {
   try {
-    const platform = getVirtualEnvironmentName()
-    const [engine, version] = parseRubyEngineAndVersion(core.getInput('ruby-version'))
-
-    let installer
-    if (platform === 'windows-latest' && engine !== 'jruby') {
-      installer = require('./windows')
-    } else {
-      installer = require('./ruby-install-builder')
-    }
-
-    const engineVersions = installer.getAvailableVersions(platform, engine)
-    const ruby = validateRubyEngineAndVersion(platform, engineVersions, engine, version)
-
-    const rubyPrefix = await installer.install(platform, ruby)
-    core.setOutput('ruby-prefix', rubyPrefix)
+    await setupRuby()
   } catch (error) {
     core.setFailed(error.message)
   }
 }
 
+// entry point when this action is run from other actions
+export async function setupRuby(options = {}) {
+  const inputs = { ...options }
+  for (const key in inputDefaults) {
+    if (!Object.prototype.hasOwnProperty.call(inputs, key)) {
+      inputs[key] = core.getInput(key) || inputDefaults[key]
+    }
+  }
+
+  process.chdir(inputs['working-directory'])
+
+  const platform = common.getVirtualEnvironmentName()
+  const [engine, parsedVersion] = parseRubyEngineAndVersion(inputs['ruby-version'])
+
+  let installer
+  if (platform.startsWith('windows-') && engine !== 'jruby') {
+    installer = require('./windows')
+  } else {
+    installer = require('./ruby-builder')
+  }
+
+  const engineVersions = installer.getAvailableVersions(platform, engine)
+  const version = validateRubyEngineAndVersion(platform, engineVersions, engine, parsedVersion)
+
+  createGemRC()
+  envPreInstall()
+
+  const rubyPrefix = await installer.install(platform, engine, version)
+
+  // When setup-ruby is used by other actions, this allows code in them to run
+  // before 'bundle install'.  Installed dependencies may require additional
+  // libraries & headers, build tools, etc.
+  if (inputs['afterSetupPathHook'] instanceof Function) {
+    await inputs['afterSetupPathHook']({ platform, rubyPrefix, engine, version })
+  }
+
+  if (inputs['bundler'] !== 'none') {
+    const [gemfile, lockFile] = bundler.detectGemfiles()
+
+    const bundlerVersion = await common.measure('Installing Bundler', async () =>
+        bundler.installBundler(inputs['bundler'], lockFile, platform, rubyPrefix, engine, version))
+
+    if (inputs['bundler-cache'] === 'true') {
+      await common.measure('bundle install', async () =>
+          bundler.bundleInstall(gemfile, lockFile, platform, engine, version, bundlerVersion, inputs['cache-version']))
+    }
+  }
+
+  core.setOutput('ruby-prefix', rubyPrefix)
+}
+
 function parseRubyEngineAndVersion(rubyVersion) {
+  if (rubyVersion === 'default') {
+    if (fs.existsSync('.ruby-version')) {
+      rubyVersion = '.ruby-version'
+    } else if (fs.existsSync('.tool-versions')) {
+      rubyVersion = '.tool-versions'
+    } else {
+      throw new Error('input ruby-version needs to be specified if no .ruby-version or .tool-versions file exists')
+    }
+  }
+
   if (rubyVersion === '.ruby-version') { // Read from .ruby-version
     rubyVersion = fs.readFileSync('.ruby-version', 'utf8').trim()
     console.log(`Using ${rubyVersion} as input from file .ruby-version`)
+  } else if (rubyVersion === '.tool-versions') { // Read from .tool-versions
+    const toolVersions = fs.readFileSync('.tool-versions', 'utf8').trim()
+    const rubyLine = toolVersions.split(/\r?\n/).filter(e => e.match(/^ruby\s/))[0]
+    rubyVersion = rubyLine.match(/^ruby\s+(.+)$/)[1]
+    console.log(`Using ${rubyVersion} as input from file .tool-versions`)
   }
 
   let engine, version
-  if (rubyVersion.match(/^\d+/)) { // X.Y.Z => ruby-X.Y.Z
+  if (rubyVersion.match(/^(\d+)/) || common.isHeadVersion(rubyVersion)) { // X.Y.Z => ruby-X.Y.Z
     engine = 'ruby'
     version = rubyVersion
   } else if (!rubyVersion.includes('-')) { // myruby -> myruby-stableVersion
     engine = rubyVersion
-    version = '' // Let the logic below find the version
+    version = '' // Let the logic in validateRubyEngineAndVersion() find the version
   } else { // engine-X.Y.Z
-    [engine, version] = rubyVersion.split('-', 2)
+    [engine, version] = common.partition(rubyVersion, '-')
   }
 
   return [engine, version]
 }
 
-function validateRubyEngineAndVersion(platform, engineVersions, engine, version) {
+function validateRubyEngineAndVersion(platform, engineVersions, engine, parsedVersion) {
   if (!engineVersions) {
     throw new Error(`Unknown engine ${engine} on ${platform}`)
   }
 
-  if (!engineVersions.includes(version)) {
+  let version = parsedVersion
+  if (!engineVersions.includes(parsedVersion)) {
     const latestToFirstVersion = engineVersions.slice().reverse()
-    const found = latestToFirstVersion.find(v => v.startsWith(version))
+    // Try to match stable versions first, so an empty version (engine-only) matches the latest stable version
+    let found = latestToFirstVersion.find(v => common.isStableVersion(v) && v.startsWith(parsedVersion))
+    if (!found) {
+      // Exclude head versions, they must be exact matches
+      found = latestToFirstVersion.find(v => !common.isHeadVersion(v) && v.startsWith(parsedVersion))
+    }
+
     if (found) {
       version = found
     } else {
-      throw new Error(`Unknown version ${version} for ${engine} on ${platform}
+      throw new Error(`Unknown version ${parsedVersion} for ${engine} on ${platform}
         available versions for ${engine} on ${platform}: ${engineVersions.join(', ')}
-        File an issue at https://github.com/eregon/use-ruby-action/issues if would like support for a new version`)
+        Make sure you use the latest version of the action with - uses: ruby/setup-ruby@v1
+        File an issue at https://github.com/ruby/setup-ruby/issues if would like support for a new version`)
     }
   }
 
-  return engine + '-' + version
+  return version
 }
 
-function getVirtualEnvironmentName() {
-  const platform = os.platform()
-  if (platform === 'linux') {
-    return `ubuntu-${findUbuntuVersion()}`
-  } else if (platform === 'darwin') {
-    return 'macos-latest'
-  } else if (platform === 'win32') {
-    return 'windows-latest'
-  } else {
-    throw new Error(`Unknown platform ${platform}`)
+function createGemRC() {
+  const gemrc = path.join(os.homedir(), '.gemrc')
+  if (!fs.existsSync(gemrc)) {
+    fs.writeFileSync(gemrc, `gem: --no-document${os.EOL}`)
   }
 }
 
-function findUbuntuVersion() {
-  const lsb_release = fs.readFileSync('/etc/lsb-release', 'utf8')
-  const match = lsb_release.match(/^DISTRIB_RELEASE=(\d+\.\d+)$/m)
-  if (match) {
-    return match[1]
-  } else {
-    throw new Error('Could not find Ubuntu version')
+// sets up ENV variables
+// currently only used on Windows runners
+function envPreInstall() {
+  const ENV = process.env
+  if (windows) {
+    // puts normal Ruby temp folder on SSD
+    core.exportVariable('TMPDIR', ENV['RUNNER_TEMP'])
+    // bash - sets home to match native windows, normally C:\Users\<user name>
+    core.exportVariable('HOME', ENV['HOMEDRIVE'] + ENV['HOMEPATH'])
+    // bash - needed to maintain Path from Windows
+    core.exportVariable('MSYS2_PATH_TYPE', 'inherit')
   }
 }
 
-run()
+if (__filename.endsWith('index.js')) { run() }

package.json

@@ -1,15 +1,14 @@
 {
-  "name": "use-ruby-action",
+  "name": "setup-ruby",
   "version": "0.1.0",
   "description": "Download a prebuilt Ruby and add it to the PATH in 5 seconds",
   "main": "index.js",
   "scripts": {
-    "lint": "eslint *.js",
     "package": "ncc build index.js -o dist"
   },
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/eregon/use-ruby-action.git"
+    "url": "git+https://github.com/ruby/setup-ruby.git"
   },
   "keywords": [
     "GitHub",
@@ -19,18 +18,17 @@
   "author": "Benoit Daloze",
   "license": "MIT",
   "bugs": {
-    "url": "https://github.com/eregon/use-ruby-action/issues"
+    "url": "https://github.com/ruby/setup-ruby/issues"
   },
-  "homepage": "https://github.com/eregon/use-ruby-action",
+  "homepage": "https://github.com/ruby/setup-ruby",
   "dependencies": {
-    "@actions/core": "^1.1.1",
-    "@actions/exec": "^1.0.1",
-    "@actions/io": "^1.0.1",
-    "@actions/tool-cache": "^1.1.2",
-    "axios": "^0.19.0"
+    "@actions/cache": "^1.0.5",
+    "@actions/core": "^1.2.6",
+    "@actions/exec": "^1.0.3",
+    "@actions/io": "^1.0.2",
+    "@actions/tool-cache": "^1.3.4"
   },
   "devDependencies": {
-    "@zeit/ncc": "^0.20.5",
-    "eslint": "^6.3.0"
+    "@vercel/ncc": "^0.23.0"
   }
 }

pre-commit

@@ -0,0 +1,5 @@
+#!/usr/bin/sh
+set -e
+yarn install
+yarn run package
+exec git add dist/index.js

ruby-builder-versions.js

@@ -0,0 +1,28 @@
+export function getVersions(platform) {
+  const versions = {
+    "ruby": [
+      "2.1.9",
+      "2.2.10",
+      "2.3.0", "2.3.1", "2.3.2", "2.3.3", "2.3.4", "2.3.5", "2.3.6", "2.3.7", "2.3.8",
+      "2.4.0", "2.4.1", "2.4.2", "2.4.3", "2.4.4", "2.4.5", "2.4.6", "2.4.7", "2.4.9", "2.4.10",
+      "2.5.0", "2.5.1", "2.5.2", "2.5.3", "2.5.4", "2.5.5", "2.5.6", "2.5.7", "2.5.8", "2.5.9",
+      "2.6.0", "2.6.1", "2.6.2", "2.6.3", "2.6.4", "2.6.5", "2.6.6", "2.6.7",
+      "2.7.0", "2.7.1", "2.7.2", "2.7.3",
+      "3.0.0-preview1", "3.0.0-preview2", "3.0.0-rc1", "3.0.0", "3.0.1",
+      "head", "debug",
+    ],
+    "jruby": [
+      "9.1.17.0",
+      "9.2.9.0", "9.2.10.0", "9.2.11.0", "9.2.11.1", "9.2.12.0", "9.2.13.0", "9.2.14.0", "9.2.15.0", "9.2.16.0", "9.2.17.0",
+      "head"
+    ],
+    "truffleruby": [
+      "19.3.0", "19.3.1",
+      "20.0.0", "20.1.0", "20.2.0", "20.3.0",
+      "21.0.0", "21.1.0",
+      "head"
+    ]
+  }
+
+  return versions
+}

ruby-builder.js

@@ -0,0 +1,86 @@
+const os = require('os')
+const path = require('path')
+const exec = require('@actions/exec')
+const io = require('@actions/io')
+const tc = require('@actions/tool-cache')
+const common = require('./common')
+const rubyBuilderVersions = require('./ruby-builder-versions')
+
+const builderReleaseTag = 'toolcache'
+const releasesURL = 'https://github.com/ruby/ruby-builder/releases'
+
+const windows = common.windows
+
+export function getAvailableVersions(platform, engine) {
+  return rubyBuilderVersions.getVersions(platform)[engine]
+}
+
+export async function install(platform, engine, version) {
+  let rubyPrefix, inToolCache
+  if (common.shouldUseToolCache(engine, version)) {
+    inToolCache = tc.find('Ruby', version)
+    if (inToolCache) {
+      rubyPrefix = inToolCache
+    } else {
+      rubyPrefix = common.getToolCacheRubyPrefix(platform, version)
+    }
+  } else if (windows) {
+    rubyPrefix = path.join(`${common.drive}:`, `${engine}-${version}`)
+  } else {
+    rubyPrefix = path.join(os.homedir(), '.rubies', `${engine}-${version}`)
+  }
+
+  // Set the PATH now, so the MSYS2 'tar' is in Path on Windows
+  common.setupPath([path.join(rubyPrefix, 'bin')])
+
+  if (!inToolCache) {
+    await downloadAndExtract(platform, engine, version, rubyPrefix);
+  }
+
+  return rubyPrefix
+}
+
+async function downloadAndExtract(platform, engine, version, rubyPrefix) {
+  const parentDir = path.dirname(rubyPrefix)
+
+  await io.rmRF(rubyPrefix)
+  await io.mkdirP(parentDir)
+
+  const downloadPath = await common.measure('Downloading Ruby', async () => {
+    const url = getDownloadURL(platform, engine, version)
+    console.log(url)
+    return await tc.downloadTool(url)
+  })
+
+  await common.measure('Extracting Ruby', async () => {
+    if (windows) {
+      // Windows 2016 doesn't have system tar, use MSYS2's, it needs unix style paths
+      await exec.exec('tar', ['-xz', '-C', common.win2nix(parentDir), '-f', common.win2nix(downloadPath)])
+    } else {
+      await exec.exec('tar', ['-xz', '-C', parentDir, '-f', downloadPath])
+    }
+  })
+
+  if (common.shouldUseToolCache(engine, version)) {
+    common.createToolCacheCompleteFile(rubyPrefix)
+  }
+}
+
+function getDownloadURL(platform, engine, version) {
+  let builderPlatform = platform
+  if (platform.startsWith('windows-')) {
+    builderPlatform = 'windows-latest'
+  } else if (platform.startsWith('macos-')) {
+    builderPlatform = 'macos-latest'
+  }
+
+  if (common.isHeadVersion(version)) {
+    return getLatestHeadBuildURL(builderPlatform, engine, version)
+  } else {
+    return `${releasesURL}/download/${builderReleaseTag}/${engine}-${version}-${builderPlatform}.tar.gz`
+  }
+}
+
+function getLatestHeadBuildURL(platform, engine, version) {
+  return `https://github.com/ruby/${engine}-dev-builder/releases/latest/download/${engine}-${version}-${platform}.tar.gz`
+}

ruby-install-builder-versions.js

@@ -1,25 +0,0 @@
-export function getVersions(platform) {
-  const versions = {
-    "ruby": [
-      "2.3.0", "2.3.1", "2.3.2", "2.3.3", "2.3.4", "2.3.5", "2.3.6", "2.3.7", "2.3.8",
-      "2.4.0", "2.4.1", "2.4.2", "2.4.3", "2.4.4", "2.4.5", "2.4.6", "2.4.7", "2.4.9",
-      "2.5.0", "2.5.1", "2.5.2", "2.5.3", "2.5.4", "2.5.5", "2.5.6", "2.5.7",
-      "2.6.0", "2.6.1", "2.6.2", "2.6.3", "2.6.4", "2.6.5",
-      "2.7.0"
-    ],
-    "jruby": [
-      "9.2.9.0"
-    ],
-    "truffleruby": [
-      "head", "19.3.0", "19.3.1"
-    ]
-  }
-
-  if (platform === 'ubuntu-18.04') {
-    versions['rubinius'] = [
-      "4.13"
-    ]
-  }
-
-  return versions
-}

ruby-install-builder.js

@@ -1,51 +0,0 @@
-const os = require('os')
-const path = require('path')
-const core = require('@actions/core')
-const io = require('@actions/io')
-const tc = require('@actions/tool-cache')
-const rubyBuilderVersions = require('./ruby-install-builder-versions')
-const axios = require('axios')
-
-const builderReleaseTag = 'builds-newer-openssl'
-const releasesURL = 'https://github.com/eregon/ruby-install-builder/releases'
-
-const truffleRubyHeadReleaseURL = 'https://github.com/eregon/truffleruby-dev-builder/releases/download'
-const truffleRubyHeadMetadataURL = 'https://raw.githubusercontent.com/eregon/truffleruby-dev-builder/metadata/latest_build.tag'
-
-export function getAvailableVersions(platform, engine) {
-  return rubyBuilderVersions.getVersions(platform)[engine]
-}
-
-export async function install(platform, ruby) {
-  const rubyPrefix = await downloadAndExtract(platform, ruby)
-
-  core.addPath(path.join(rubyPrefix, 'bin'))
-  if (ruby.startsWith('rubinius')) {
-    core.addPath(path.join(rubyPrefix, 'gems', 'bin'))
-  }
-
-  return rubyPrefix
-}
-
-async function downloadAndExtract(platform, ruby) {
-  const rubiesDir = path.join(os.homedir(), '.rubies')
-  await io.mkdirP(rubiesDir)
-
-  const url = await getDownloadURL(platform, ruby)
-  console.log(url)
-
-  const downloadPath = await tc.downloadTool(url)
-  await tc.extractTar(downloadPath, rubiesDir)
-
-  return path.join(rubiesDir, ruby)
-}
-
-async function getDownloadURL(platform, ruby) {
-  if (ruby === 'truffleruby-head') {
-    const response = await axios.get(truffleRubyHeadMetadataURL)
-    const tag = response.data.trim()
-    return `${truffleRubyHeadReleaseURL}/${tag}/${ruby}-${platform}.tar.gz`
-  } else {
-    return `${releasesURL}/download/${builderReleaseTag}/${ruby}-${platform}.tar.gz`
-  }
-}

test_subprocess.rb

@@ -0,0 +1,13 @@
+require 'rbconfig'
+require 'stringio'
+
+puts "CPPFLAGS: #{RbConfig::CONFIG["CPPFLAGS"]}"
+
+$stderr = StringIO.new
+begin
+  system RbConfig.ruby, "-e", "p :OK"
+  out = $stderr.string
+ensure
+  $stderr = STDERR
+end
+abort out unless out.empty?

versions-strings-for-builder.rb

@@ -0,0 +1,18 @@
+hash = File.read('ruby-builder-versions.js')[/\bversions = {[^}]+}/]
+versions = eval hash
+
+by_minor = versions[:ruby].group_by { |v| v[/^\d\.\d/] }
+
+(1..7).each do |minor|
+  p by_minor["2.#{minor}"].map { |v| "ruby-#{v}" }
+end
+
+puts
+p (versions[:truffleruby] - %w[head]).map { |v| "truffleruby-#{v}" }
+
+puts
+p (versions[:jruby] - %w[head]).map { |v| "jruby-#{v}" }
+
+(versions[:jruby] - %w[head]).each do |v|
+  puts "- { os: windows-latest, jruby-version: #{v}, ruby: jruby-#{v} }"
+end

windows-versions.js

@@ -1,7 +1,9 @@
 export const versions = {
-  "2.3.0": "https://dl.bintray.com/oneclick/rubyinstaller/ruby-2.3.0-x64-mingw32.7z",
-  "2.3.1": "https://dl.bintray.com/oneclick/rubyinstaller/ruby-2.3.1-x64-mingw32.7z",
-  "2.3.3": "https://dl.bintray.com/oneclick/rubyinstaller/ruby-2.3.3-x64-mingw32.7z",
+  "2.1.9": "https://github.com/oneclick/rubyinstaller/releases/download/ruby-2.1.9/ruby-2.1.9-x64-mingw32.7z",
+  "2.2.6": "https://github.com/oneclick/rubyinstaller/releases/download/ruby-2.2.6/ruby-2.2.6-x64-mingw32.7z",
+  "2.3.0": "https://github.com/oneclick/rubyinstaller/releases/download/ruby-2.3.0/ruby-2.3.0-x64-mingw32.7z",
+  "2.3.1": "https://github.com/oneclick/rubyinstaller/releases/download/ruby-2.3.1/ruby-2.3.1-x64-mingw32.7z",
+  "2.3.3": "https://github.com/oneclick/rubyinstaller/releases/download/ruby-2.3.3/ruby-2.3.3-x64-mingw32.7z",
   "2.4.1": "https://github.com/oneclick/rubyinstaller2/releases/download/2.4.1-2/rubyinstaller-2.4.1-2-x64.7z",
   "2.4.2": "https://github.com/oneclick/rubyinstaller2/releases/download/rubyinstaller-2.4.2-2/rubyinstaller-2.4.2-2-x64.7z",
   "2.4.3": "https://github.com/oneclick/rubyinstaller2/releases/download/rubyinstaller-2.4.3-2/rubyinstaller-2.4.3-2-x64.7z",
@@ -10,17 +12,30 @@ export const versions = {
   "2.4.6": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.4.6-1/rubyinstaller-2.4.6-1-x64.7z",
   "2.4.7": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.4.7-1/rubyinstaller-2.4.7-1-x64.7z",
   "2.4.9": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.4.9-1/rubyinstaller-2.4.9-1-x64.7z",
+  "2.4.10": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.4.10-1/rubyinstaller-2.4.10-1-x64.7z",
   "2.5.0": "https://github.com/oneclick/rubyinstaller2/releases/download/rubyinstaller-2.5.0-2/rubyinstaller-2.5.0-2-x64.7z",
   "2.5.1": "https://github.com/oneclick/rubyinstaller2/releases/download/rubyinstaller-2.5.1-2/rubyinstaller-2.5.1-2-x64.7z",
   "2.5.3": "https://github.com/oneclick/rubyinstaller2/releases/download/rubyinstaller-2.5.3-1/rubyinstaller-2.5.3-1-x64.7z",
   "2.5.5": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.5.5-1/rubyinstaller-2.5.5-1-x64.7z",
   "2.5.6": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.5.6-1/rubyinstaller-2.5.6-1-x64.7z",
   "2.5.7": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.5.7-1/rubyinstaller-2.5.7-1-x64.7z",
+  "2.5.8": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.5.8-2/rubyinstaller-2.5.8-2-x64.7z",
+  "2.5.9": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.5.9-1/rubyinstaller-2.5.9-1-x64.7z",
   "2.6.0": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.6.0-1/rubyinstaller-2.6.0-1-x64.7z",
   "2.6.1": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.6.1-1/rubyinstaller-2.6.1-1-x64.7z",
   "2.6.2": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.6.2-1/rubyinstaller-2.6.2-1-x64.7z",
   "2.6.3": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.6.3-1/rubyinstaller-2.6.3-1-x64.7z",
   "2.6.4": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.6.4-1/rubyinstaller-2.6.4-1-x64.7z",
   "2.6.5": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.6.5-1/rubyinstaller-2.6.5-1-x64.7z",
-  "2.7.0": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.7.0-1/rubyinstaller-2.7.0-1-x64.7z"
+  "2.6.6": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.6.6-2/rubyinstaller-2.6.6-2-x64.7z",
+  "2.6.7": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.6.7-1/rubyinstaller-2.6.7-1-x64.7z",
+  "2.7.0": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.7.0-1/rubyinstaller-2.7.0-1-x64.7z",
+  "2.7.1": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.7.1-1/rubyinstaller-2.7.1-1-x64.7z",
+  "2.7.2": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.7.2-1/rubyinstaller-2.7.2-1-x64.7z",
+  "2.7.3": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-2.7.3-1/rubyinstaller-2.7.3-1-x64.7z",
+  "3.0.0": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-3.0.0-1/rubyinstaller-3.0.0-1-x64.7z",
+  "3.0.1": "https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-3.0.1-1/rubyinstaller-3.0.1-1-x64.7z",
+  "head": "https://github.com/oneclick/rubyinstaller2/releases/download/rubyinstaller-head/rubyinstaller-head-x64.7z",
+  "mingw": "https://github.com/MSP-Greg/ruby-loco/releases/download/ruby-master/ruby-mingw.7z",
+  "mswin": "https://github.com/MSP-Greg/ruby-loco/releases/download/ruby-master/ruby-mswin.7z"
 }

windows.js

@@ -2,11 +2,24 @@
 // https://github.com/MSP-Greg/actions-ruby/blob/master/lib/main.js
 
 const fs = require('fs')
+const path = require('path')
+const cp = require('child_process')
 const core = require('@actions/core')
 const exec = require('@actions/exec')
+const io = require('@actions/io')
 const tc = require('@actions/tool-cache')
+const common = require('./common')
 const rubyInstallerVersions = require('./windows-versions').versions
 
+const drive = common.drive
+
+// needed for 2.1, 2.2, 2.3, and mswin, cert file used by Git for Windows
+const certFile = 'C:\\Program Files\\Git\\mingw64\\ssl\\cert.pem'
+
+// location & path for old RubyInstaller DevKit (MSYS), Ruby 2.1, 2.2 and 2.3
+const msys = `${drive}:\\DevKit64`
+const msysPathEntries = [`${msys}\\mingw\\x86_64-w64-mingw32\\bin`, `${msys}\\mingw\\bin`, `${msys}\\bin`]
+
 export function getAvailableVersions(platform, engine) {
   if (engine === 'ruby') {
     return Object.keys(rubyInstallerVersions)
@@ -15,67 +28,128 @@ export function getAvailableVersions(platform, engine) {
   }
 }
 
-export async function install(platform, ruby) {
-  const version = ruby.split('-', 2)[1]
+export async function install(platform, engine, version) {
   const url = rubyInstallerVersions[version]
-  console.log(url)
 
   if (!url.endsWith('.7z')) {
-    throw new Error('URL should end in .7z')
+    throw new Error(`URL should end in .7z: ${url}`)
   }
   const base = url.slice(url.lastIndexOf('/') + 1, url.length - '.7z'.length)
 
-  // Extract to SSD, see https://github.com/eregon/use-ruby-action/pull/14
-  const drive = (process.env['GITHUB_WORKSPACE'] || 'C')[0]
-
-  const downloadPath = await tc.downloadTool(url)
-  await exec.exec(`7z x ${downloadPath} -xr!${base}\\share\\doc -o${drive}:\\`)
-  const rubyPrefix = `${drive}:\\${base}`
-
-  const [hostedRuby, msys2] = await linkMSYS2()
-  const newPath = setupPath(msys2, rubyPrefix)
-  core.exportVariable('PATH', newPath)
-
-  if (version.startsWith('2.3')) {
-    core.exportVariable('SSL_CERT_FILE', `${hostedRuby}\\ssl\\cert.pem`)
+  let rubyPrefix, inToolCache
+  if (common.shouldUseToolCache(engine, version)) {
+    inToolCache = tc.find('Ruby', version)
+    if (inToolCache) {
+      rubyPrefix = inToolCache
+    } else {
+      rubyPrefix = common.getToolCacheRubyPrefix(platform, version)
+    }
+  } else {
+    rubyPrefix = `${drive}:\\${base}`
   }
 
-  if (!fs.existsSync(`${rubyPrefix}\\bin\\bundle.cmd`)) {
-    await exec.exec(`${rubyPrefix}\\bin\\gem install bundler -v "~> 1" --no-document`)
+  let toolchainPaths = (version === 'mswin') ? await setupMSWin() : await setupMingw(version)
+
+  common.setupPath([`${rubyPrefix}\\bin`, ...toolchainPaths])
+
+  if (!inToolCache) {
+    await downloadAndExtract(engine, version, url, base, rubyPrefix);
   }
 
   return rubyPrefix
 }
 
-async function linkMSYS2() {
-  const toolCacheVersions = tc.findAllVersions('Ruby')
-  toolCacheVersions.sort()
-  if (toolCacheVersions.length === 0) {
-    throw new Error('Could not find MSYS2 in the toolcache')
+async function downloadAndExtract(engine, version, url, base, rubyPrefix) {
+  const parentDir = path.dirname(rubyPrefix)
+
+  const downloadPath = await common.measure('Downloading Ruby', async () => {
+    console.log(url)
+    return await tc.downloadTool(url)
+  })
+
+  await common.measure('Extracting Ruby', async () =>
+    exec.exec('7z', ['x', downloadPath, `-xr!${base}\\share\\doc`, `-o${parentDir}`], { silent: true }))
+
+  if (base !== path.basename(rubyPrefix)) {
+    await io.mv(path.join(parentDir, base), rubyPrefix)
   }
-  const latestVersion = toolCacheVersions.slice(-1)[0]
-  const latestHostedRuby = tc.find('Ruby', latestVersion)
 
-  const hostedMSYS2 = `${latestHostedRuby}\\msys64`
-  const msys2 = 'C:\\msys64'
-  await exec.exec(`cmd /c mklink /D ${msys2} ${hostedMSYS2}`)
-  return [latestHostedRuby, msys2]
+  if (common.shouldUseToolCache(engine, version)) {
+    common.createToolCacheCompleteFile(rubyPrefix)
+  }
 }
 
-function setupPath(msys2, rubyPrefix) {
-  let path = process.env['PATH'].split(';')
+async function setupMingw(version) {
+  core.exportVariable('MAKE', 'make.exe')
 
-  // Remove conflicting dev tools from PATH
-  path = path.filter(e => !e.match(/\b(Chocolatey|CMake|mingw64|OpenSSL|Strawberry)\b/))
+  if (version.match(/^2\.[123]/)) {
+    core.exportVariable('SSL_CERT_FILE', certFile)
+    await common.measure('Installing MSYS', async () => installMSYS(version))
+    return msysPathEntries
+  } else {
+    return []
+  }
+}
 
-  // Remove default Ruby in PATH
-  path = path.filter(e => !e.match(/\bRuby\b/))
+// Ruby 2.1, 2.2 and 2.3
+async function installMSYS(version) {
+  const url = 'https://github.com/oneclick/rubyinstaller/releases/download/devkit-4.7.2/DevKit-mingw64-64-4.7.2-20130224-1432-sfx.exe'
+  const downloadPath = await tc.downloadTool(url)
+  await exec.exec('7z', ['x', downloadPath, `-o${msys}`], { silent: true })
 
-  // Add MSYS2 in PATH
-  path.unshift(`${msys2}\\mingw64\\bin`, `${msys2}\\usr\\bin`)
+  // below are set in the old devkit.rb file ?
+  core.exportVariable('RI_DEVKIT', msys)
+  core.exportVariable('CC' , 'gcc')
+  core.exportVariable('CXX', 'g++')
+  core.exportVariable('CPP', 'cpp')
+  core.info(`Installed RubyInstaller DevKit for Ruby ${version}`)
+}
 
-  // Add the downloaded Ruby in PATH
-  path.unshift(`${rubyPrefix}\\bin`)
+async function setupMSWin() {
+  core.exportVariable('MAKE', 'nmake.exe')
 
-  return path.join(';')
+  // All standard MSVC OpenSSL builds use C:\Program Files\Common Files\SSL
+  const certsDir = 'C:\\Program Files\\Common Files\\SSL\\certs'
+  if (!fs.existsSync(certsDir)) {
+    fs.mkdirSync(certsDir)
+  }
+
+  // cert.pem location is hard-coded by OpenSSL msvc builds
+  const cert = 'C:\\Program Files\\Common Files\\SSL\\cert.pem'
+  if (!fs.existsSync(cert)) {
+    fs.copyFileSync(certFile, cert)
+  }
+
+  return await common.measure('Setting up MSVC environment', async () => addVCVARSEnv())
+}
+
+/* Sets MSVC environment for use in Actions
+ *   allows steps to run without running vcvars*.bat, also for PowerShell
+ *   adds a convenience VCVARS environment variable
+ *   this assumes a single Visual Studio version being available in the windows-latest image */
+export function addVCVARSEnv() {
+  const vcVars = '"C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\Enterprise\\VC\\Auxiliary\\Build\\vcvars64.bat"'
+  core.exportVariable('VCVARS', vcVars)
+
+  let newEnv = new Map()
+  let cmd = `cmd.exe /c "${vcVars} && set"`
+  let newSet = cp.execSync(cmd).toString().trim().split(/\r?\n/)
+  newSet = newSet.filter(line => line.match(/\S=\S/))
+  newSet.forEach(s => {
+    let [k,v] = common.partition(s, '=')
+    newEnv.set(k,v)
+  })
+
+  let newPathEntries = undefined
+  for (let [k, v] of newEnv) {
+    if (process.env[k] !== v) {
+      if (/^Path$/i.test(k)) {
+        const newPathStr = v.replace(`${path.delimiter}${process.env['Path']}`, '')
+        newPathEntries = newPathStr.split(path.delimiter)
+      } else {
+        core.exportVariable(k, v)
+      }
+    }
+  }
+  return newPathEntries
 }