All 33 Ruby versions between 2.3.0 and 2.7.0 are now supported

README.md

@@ -11,7 +11,7 @@ This action currently supports these versions of MRI, JRuby and TruffleRuby:
 
 | Interpreter | Versions |
 | ----------- | -------- |
-| Ruby | 2.3.8, 2.4.9, 2.5.7, 2.6.5, 2.7.0 |
+| 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 |
 
@@ -88,7 +88,11 @@ jobs:
 
 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), the latest version of Bundler is installed when that Ruby was built.
+Otherwise (Ruby < 2.6), Bundler 1 is installed when that Ruby was built.
+
+### Caching `bundle install`
+
+See this [example](https://github.com/actions/cache/blob/master/examples.md#ruby---gem) using [actions/cache](https://github.com/actions/cache).
 
 ## Limitations
 

dist/index.js

@@ -6495,7 +6495,7 @@ async function downloadExtractAndSetPATH(ruby) {
   core.exportVariable('PATH', newPath)
 
   if (!fs.existsSync(`${rubyPrefix}\\bin\\bundle.cmd`)) {
-    await exec.exec(`${rubyPrefix}\\bin\\gem install bundler --no-document`)
+    await exec.exec(`${rubyPrefix}\\bin\\gem install bundler -v "~> 1" --no-document`)
   }
 
   return rubyPrefix
@@ -6526,7 +6526,7 @@ function setupPath(msys2, rubyPrefix) {
   path = path.filter(e => !e.match(/\bRuby\b/))
 
   // Add MSYS2 in PATH
-  path.unshift(`${msys2}\\mingw64`, `${msys2}\\usr`)
+  path.unshift(`${msys2}\\mingw64\\bin`, `${msys2}\\usr\\bin`)
 
   // Add the downloaded Ruby in PATH
   path.unshift(`${rubyPrefix}\\bin`)

windows.js

@@ -28,7 +28,7 @@ export async function downloadExtractAndSetPATH(ruby) {
   core.exportVariable('PATH', newPath)
 
   if (!fs.existsSync(`${rubyPrefix}\\bin\\bundle.cmd`)) {
-    await exec.exec(`${rubyPrefix}\\bin\\gem install bundler --no-document`)
+    await exec.exec(`${rubyPrefix}\\bin\\gem install bundler -v "~> 1" --no-document`)
   }
 
   return rubyPrefix
@@ -59,7 +59,7 @@ function setupPath(msys2, rubyPrefix) {
   path = path.filter(e => !e.match(/\bRuby\b/))
 
   // Add MSYS2 in PATH
-  path.unshift(`${msys2}\\mingw64`, `${msys2}\\usr`)
+  path.unshift(`${msys2}\\mingw64\\bin`, `${msys2}\\usr\\bin`)
 
   // Add the downloaded Ruby in PATH
   path.unshift(`${rubyPrefix}\\bin`)