Extract utility methods to common.js

common.js

@@ -0,0 +1,25 @@
+const os = require('os')
+const fs = require('fs')
+
+export 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 ${platform}`)
+  }
+}
+
+function findUbuntuVersion() {
+  const lsb_release = fs.readFileSync('/etc/lsb-release', 'utf8')
+  const match = lsb_release.match(/^DISTRIB_RELEASE=(\d+\.\d+)$/m)
+  if (match) {
+    return match[1]
+  } else {
+    throw new Error('Could not find Ubuntu version')
+  }
+}