Add test checking using an exact Bundler version works

.github/workflows/test.yml

@@ -102,6 +102,17 @@ jobs:
       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: 2.6
+        bundler: 2.1.4
+    - run: bundle --version | grep -F 2.1.4
+
   lint:
     runs-on: ubuntu-20.04
     steps:

action.yml

@@ -11,7 +11,7 @@ inputs:
     default: 'default'
   bundler:
     description: |
-      The version of Bundler to install. Either 'none', 1, 2, 'latest' or 'Gemfile.lock'.
+      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

common.js

@@ -40,6 +40,25 @@ 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)
+  } 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')

dist/index.js

@@ -32114,6 +32114,8 @@ __webpack_require__.r(__webpack_exports__);
 /* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "measure", function() { return measure; });
 /* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "isHeadVersion", function() { return isHeadVersion; });
 /* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "isStableVersion", function() { return isStableVersion; });
+/* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "isBundler2Default", function() { return isBundler2Default; });
+/* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "floatVersion", function() { return floatVersion; });
 /* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "hashFile", function() { return hashFile; });
 /* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "getVirtualEnvironmentName", function() { return getVirtualEnvironmentName; });
 /* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "shouldUseToolCache", function() { return shouldUseToolCache; });
@@ -32163,6 +32165,25 @@ function isStableVersion(rubyVersion) {
   return /^\d+(\.\d+)*$/.test(rubyVersion)
 }
 
+function isBundler2Default(engine, rubyVersion) {
+  if (engine === 'ruby') {
+    return isHeadVersion(rubyVersion) || floatVersion(rubyVersion) >= 2.7
+  } else if (engine === 'truffleruby') {
+    return isHeadVersion(rubyVersion)
+  } else {
+    return false
+  }
+}
+
+function floatVersion(rubyVersion) {
+  const match = rubyVersion.match(/^\d+\.\d+/)
+  if (match) {
+    return parseFloat(match[0])
+  } else {
+    return 0.0
+  }
+}
+
 async function hashFile(file) {
   // See https://github.com/actions/runner/blob/master/src/Misc/expressionFunc/hashFiles/src/hashFiles.ts
   const hash = crypto.createHash('sha256')
@@ -51375,9 +51396,8 @@ function readBundledWithFromGemfileLock(lockFile) {
       const nextLine = lines[bundledWithLine+1]
       if (nextLine && /^\d+/.test(nextLine.trim())) {
         const bundlerVersion = nextLine.trim()
-        const majorVersion = bundlerVersion.match(/^\d+/)[0]
-        console.log(`Using Bundler ${majorVersion} from ${lockFile} BUNDLED WITH ${bundlerVersion}`)
-        return majorVersion
+        console.log(`Using Bundler ${bundlerVersion} from ${lockFile} BUNDLED WITH ${bundlerVersion}`)
+        return bundlerVersion
       }
     }
   }
@@ -51405,7 +51425,7 @@ async function installBundler(bundlerVersionInput, lockFile, platform, rubyPrefi
     throw new Error(`Cannot parse bundler input: ${bundlerVersion}`)
   }
 
-  if (engine === 'ruby' && rubyVersion.match(/^2\.[12]/)) {
+  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.startsWith('2.3')) {
@@ -51416,9 +51436,9 @@ async function installBundler(bundlerVersionInput, lockFile, platform, rubyPrefi
     bundlerVersion = '1'
   }
 
-  if ((engine === 'ruby' || engine === 'truffleruby') && common.isHeadVersion(rubyVersion) && bundlerVersion === '2') {
+  if (common.isHeadVersion(rubyVersion) && common.isBundler2Default(engine, rubyVersion) && bundlerVersion.startsWith('2')) {
     console.log(`Using Bundler 2 shipped with ${engine}-${rubyVersion}`)
-  } else if (engine === 'truffleruby' && !common.isHeadVersion(rubyVersion) && bundlerVersion === '1') {
+  } 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')
@@ -51434,20 +51454,25 @@ async function bundleInstall(gemfile, lockFile, platform, engine, rubyVersion, b
     return false
   }
 
-  // Before the lockfile exists, we need to specify which Bundler version to use explicitly
-  const optionsWithBundlerVersion = { env: { ...process.env, BUNDLER_VERSION: bundlerVersion } }
+  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 path = 'vendor/bundle'
 
-  await exec.exec('bundle', ['config', '--local', 'path', path], optionsWithBundlerVersion)
+  await exec.exec('bundle', ['config', '--local', 'path', path], envOptions)
 
   if (fs.existsSync(lockFile)) {
-    await exec.exec('bundle', ['config', '--local', 'deployment', 'true'], optionsWithBundlerVersion)
+    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'], optionsWithBundlerVersion)
+    await exec.exec('bundle', ['lock'], envOptions)
   }
 
   // cache key

index.js

@@ -181,9 +181,8 @@ function readBundledWithFromGemfileLock(lockFile) {
       const nextLine = lines[bundledWithLine+1]
       if (nextLine && /^\d+/.test(nextLine.trim())) {
         const bundlerVersion = nextLine.trim()
-        const majorVersion = bundlerVersion.match(/^\d+/)[0]
-        console.log(`Using Bundler ${majorVersion} from ${lockFile} BUNDLED WITH ${bundlerVersion}`)
-        return majorVersion
+        console.log(`Using Bundler ${bundlerVersion} from ${lockFile} BUNDLED WITH ${bundlerVersion}`)
+        return bundlerVersion
       }
     }
   }
@@ -211,7 +210,7 @@ async function installBundler(bundlerVersionInput, lockFile, platform, rubyPrefi
     throw new Error(`Cannot parse bundler input: ${bundlerVersion}`)
   }
 
-  if (engine === 'ruby' && rubyVersion.match(/^2\.[12]/)) {
+  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.startsWith('2.3')) {
@@ -222,9 +221,9 @@ async function installBundler(bundlerVersionInput, lockFile, platform, rubyPrefi
     bundlerVersion = '1'
   }
 
-  if ((engine === 'ruby' || engine === 'truffleruby') && common.isHeadVersion(rubyVersion) && bundlerVersion === '2') {
+  if (common.isHeadVersion(rubyVersion) && common.isBundler2Default(engine, rubyVersion) && bundlerVersion.startsWith('2')) {
     console.log(`Using Bundler 2 shipped with ${engine}-${rubyVersion}`)
-  } else if (engine === 'truffleruby' && !common.isHeadVersion(rubyVersion) && bundlerVersion === '1') {
+  } 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')
@@ -240,20 +239,25 @@ async function bundleInstall(gemfile, lockFile, platform, engine, rubyVersion, b
     return false
   }
 
-  // Before the lockfile exists, we need to specify which Bundler version to use explicitly
-  const optionsWithBundlerVersion = { env: { ...process.env, BUNDLER_VERSION: bundlerVersion } }
+  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 path = 'vendor/bundle'
 
-  await exec.exec('bundle', ['config', '--local', 'path', path], optionsWithBundlerVersion)
+  await exec.exec('bundle', ['config', '--local', 'path', path], envOptions)
 
   if (fs.existsSync(lockFile)) {
-    await exec.exec('bundle', ['config', '--local', 'deployment', 'true'], optionsWithBundlerVersion)
+    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'], optionsWithBundlerVersion)
+    await exec.exec('bundle', ['lock'], envOptions)
   }
 
   // cache key