Add envPreInstall, common.setupPath, use MSYS2 bash for Windows bash

envPreInstall - sets ENV values for runners

common.setupPath - collects all Path operations into one function, runs before Ruby install

Add MSYS2 paths to all Windows builds for MSYS2 Bash use

common.js

@@ -1,4 +1,5 @@
 const os = require('os')
+const path = require('path')
 const fs = require('fs')
 const util = require('util')
 const stream = require('stream')
@@ -6,6 +7,8 @@ const crypto = require('crypto')
 const core = require('@actions/core')
 const { performance } = require('perf_hooks')
 
+const isWin = (os.platform() === 'win32')
+
 export async function measure(name, block) {
   return await core.group(name, async () => {
     const start = performance.now()
@@ -62,3 +65,30 @@ export function win2nix(path) {
   }
   return path.replace(/\\/g, '/').replace(/ /g, '\\ ')
 }
+
+export function setupPath(newPathEntries) {
+  const envPath = isWin ? 'Path' : 'PATH'
+  const originalPath = process.env[envPath].split(path.delimiter)
+  let cleanPath = originalPath.filter(entry => !/\bruby\b/i.test(entry))
+
+  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()
+  }
+  let newPath
+  if (isWin) {
+    // add MSYS2 path to all for bash shell
+    const msys2 = ['C:\\msys64\\mingw64\\bin', 'C:\\msys64\\usr\\bin']
+    newPath = [...newPathEntries, ...msys2]
+  } else {
+    newPath = newPathEntries
+  }
+  core.addPath(newPath.join(path.delimiter))
+}