Rubinius builds will no longer be provided

* This reverts commit 35f0af38a7.
* It fails for some cases like Ruby <= 2.2 and on some RubyInstaller builds,
  see https://github.com/ruby/setup-ruby/issues/98#issuecomment-723468255
* Most users will use Bundler to install rake, and that already works fine.

.github/workflows/test.yml

@@ -60,6 +60,10 @@ jobs:
             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
@@ -71,6 +75,7 @@ jobs:
     - 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
 

README.md

@@ -66,6 +66,7 @@ jobs:
     - uses: ruby/setup-ruby@v1
       with:
         ruby-version: 2.6 # Not needed with a .ruby-version file
+        bundler-cache: true # runs 'bundle install' and caches installed gems automatically
     - run: bundle install
     - run: bundle exec rake
 ```
@@ -91,6 +92,7 @@ jobs:
     - uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby }}
+        bundler-cache: true # runs 'bundle install' and caches installed gems automatically
     - run: bundle install
     - run: bundle exec rake
 ```
@@ -131,12 +133,14 @@ This action provides a way to automatically run `bundle install` and cache the r
         bundler-cache: true
 ```
 
+Note that any step doing `bundle install` (for the root `Gemfile`) or `gem install bundler` can be removed with `bundler-cache: true`.
+
 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.
 
 To perform caching, this action will use `bundle config --local path vendor/bundle`.  
-Therefore, the Bundler `path` should not be changed in your workflow for the cache to work.
+Therefore, the Bundler `path` should not be changed in your workflow for the cache to work (no `bundle config path`).
 
 ### Caching `bundle install` manually
 

dist/index.js

@@ -52860,6 +52860,7 @@ __webpack_require__.r(__webpack_exports__);
 /* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "install", function() { return install; });
 const os = __webpack_require__(87)
 const path = __webpack_require__(622)
+const core = __webpack_require__(186)
 const exec = __webpack_require__(514)
 const io = __webpack_require__(436)
 const tc = __webpack_require__(188)
@@ -52886,6 +52887,7 @@ async function downloadAndExtract(platform, engine, version) {
 
   // Set the PATH now, so the MSYS2 'tar' is in Path on Windows
   if (engine === 'rubinius') {
+    core.warning('Rubinius builds will no longer be provided, see https://github.com/ruby/setup-ruby/issues/101')
     common.setupPath([path.join(rubyPrefix, 'bin'), path.join(rubyPrefix, 'gems', 'bin')])
   } else {
     common.setupPath([path.join(rubyPrefix, 'bin')])

ruby-builder.js

@@ -1,5 +1,6 @@
 const os = require('os')
 const path = require('path')
+const core = require('@actions/core')
 const exec = require('@actions/exec')
 const io = require('@actions/io')
 const tc = require('@actions/tool-cache')
@@ -26,6 +27,7 @@ async function downloadAndExtract(platform, engine, version) {
 
   // Set the PATH now, so the MSYS2 'tar' is in Path on Windows
   if (engine === 'rubinius') {
+    core.warning('Rubinius builds will no longer be provided, see https://github.com/ruby/setup-ruby/issues/101')
     common.setupPath([path.join(rubyPrefix, 'bin'), path.join(rubyPrefix, 'gems', 'bin')])
   } else {
     common.setupPath([path.join(rubyPrefix, 'bin')])

versions-strings-for-builder.rb

@@ -3,14 +3,16 @@ versions = eval hash
 
 by_minor = versions[:ruby].group_by { |v| v[/^\d\.\d/] }
 
-p by_minor['2.1']
+(1..7).each do |minor|
-p by_minor['2.2']
-p by_minor['2.3']
-
-(4..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}" }
 
-p (versions[:truffleruby] - %w[head]).map { |v| "truffleruby-#{v}" }
+(versions[:jruby] - %w[head]).each do |v|
+  puts "- { os: windows-latest, jruby-version: #{v}, ruby: jruby-#{v} }"
+end