Cannot read property 'transformFile' of undefined

[RohithPalagiri-BO]

What is the current behavior?
I am running into this issue when attempting to build my iOS app in a Release scheme either via Xcode or via the expo CLI. I am able to successfully run the app in the simulator in debug mode.

With the expo-cli the command is npx expo run:ios --configuration Release

Please provide your exact Metro configuration and mention your Metro, node, yarn/npm version and operating system.

React Native v0.73.4
Node v18.17
Expo v50 (Bare Workflow)

This is the default generated config

// Learn more https://docs.expo.io/guides/customizing-metro
const { getDefaultConfig } = require('expo/metro-config');

/** @type {import('expo/metro-config').MetroConfig} */
const config = getDefaultConfig(__dirname);

module.exports = config;

System Information

OS: macOS 13.5.2
  CPU: (10) arm64 Apple M1 Pro
  Memory: 151.78 MB / 16.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 18.17.0
    path: ~/.nvm/versions/node/v18.17.0/bin/node
  Yarn:
    version: 1.22.15
    path: ~/.yarn/bin/yarn
  npm:
    version: 9.6.7
    path: ~/.nvm/versions/node/v18.17.0/bin/npm
  Watchman:
    version: 2024.01.22.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods:
    version: 1.15.2
    path: /opt/homebrew/bin/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 23.0
      - iOS 17.0
      - macOS 14.0
      - tvOS 17.0
      - watchOS 10.0
  Android SDK: Not Found
IDEs:
  Android Studio: 2023.1 AI-231.9392.1.2311.11330709
  Xcode:
    version: 15.0/15A240d
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 17.0.10
    path: /usr/bin/javac
  Ruby:
    version: 2.6.10
    path: /usr/bin/ruby
npmPackages:
  "@react-native-community/cli": Not Found
  react:
    installed: 18.2.0
    wanted: 18.2.0
  react-native:
    installed: 0.73.4
    wanted: 0.73.4
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: false
iOS:
  hermesEnabled: true
  newArchEnabled: false

Stacktrace

error: Cannot read property 'transformFile' of undefined
TypeError: Cannot read property 'transformFile' of undefined
TypeError: Cannot read property 'transformFile' of undefined
    at Bundler.transformFile (/Users/[USER]/Documents/Projects/sentiance-expo/node_modules/metro/src/Bundler.js:43:30)
    at async Object.transform (/Users/[USER]/Documents/Projects/sentiance-expo/node_modules/metro/src/lib/transformHelpers.js:130:12)
    at async transform (/Users/[USER]/Documents/Projects/sentiance-expo/node_modules/metro/src/DeltaBundler/Graph.js:164:26)
    at async visit (/Users/[USER]/Documents/Projects/sentiance-expo/node_modules/metro/src/DeltaBundler/buildSubgraph.js:82:29)
    at async Promise.all (index 0)
    at async buildSubgraph (/Users/[USER]/Documents/Projects/sentiance-expo/node_modules/metro/src/DeltaBundler/buildSubgraph.js:103:3)
    at async Graph._buildDelta (/Users/[USER]/Documents/Projects/sentiance-expo/node_modules/metro/src/DeltaBundler/Graph.js:157:22)
    at async Graph.initialTraverseDependencies (/Users/[USER]/Documents/Projects/sentiance-expo/node_modules/metro/src/DeltaBundler/Graph.js:140:19)
    at async DeltaCalculator._getChangedDependencies (/Users/[USER]/Documents/Projects/sentiance-expo/node_modules/metro/src/DeltaBundler/DeltaCalculator.js:151:25)
    at async DeltaCalculator.getDelta (/Users/[USER]/Documents/Projects/sentiance-expo/node_modules/metro/src/DeltaBundler/DeltaCalculator.js:68:16)

package.json

{
  "name": "sentiance-expo",
  "version": "1.0.0",
  "main": "expo-router/entry",
  "scripts": {
    "start": "expo start --dev-client",
    "android": "expo run:android",
    "ios": "expo run:ios",
    "web": "expo start --web"
  },
  "dependencies": {
    "@apollo/client": "^3.9.4",
    "@babel/runtime": "^7.23.9",
    "@mapbox/polyline": "^1.2.1",
    "@react-navigation/drawer": "^6.6.7",
    "@sentiance-react-native/core": "^6.6.0",
    "@sentiance-react-native/event-timeline": "^6.6.0",
    "@types/react": "~18.2.45",
    "axios": "^1.6.7",
    "expo": "^50.0.0",
    "expo-clipboard": "~5.0.1",
    "expo-constants": "~15.4.5",
    "expo-dev-client": "~3.3.8",
    "expo-device": "~5.9.3",
    "expo-linking": "~6.2.2",
    "expo-location": "~16.5.3",
    "expo-router": "~3.4.7",
    "expo-sensors": "~12.9.1",
    "expo-splash-screen": "~0.26.4",
    "expo-status-bar": "~1.11.1",
    "graphql": "^15.8.0",
    "react": "18.2.0",
    "react-native": "0.73.4",
    "react-native-circular-progress": "^1.3.9",
    "react-native-device-info": "^10.12.0",
    "react-native-gesture-handler": "~2.14.0",
    "react-native-maps": "1.10.0",
    "react-native-permissions": "^3.3.1",
    "react-native-reanimated": "~3.6.2",
    "react-native-safe-area-context": "4.8.2",
    "react-native-screens": "~3.29.0",
    "react-native-svg": "^14.1.0"
  },
  "devDependencies": {
    "@babel/core": "^7.20.0",
    "@babel/preset-env": "^7.23.9",
    "@types/mapbox__polyline": "^1.0.5",
    "@types/progressbar.js": "^1.1.7",
    "eslint": "^8.56.0",
    "typescript": "^5.3.3"
  },
  "private": true
}

babel.config.json

module.exports = function (api) {
  api.cache(true);
  return {
    presets: ["babel-preset-expo"],
    plugins: ["react-native-reanimated/plugin"],
  };
};

Things I've tried:

• Deleting package-lock.json, node modules, pods, podfile.lock and reinstalling all of them
• Deleting and rebuilding iOS build folder
• Attempted to downgrade to lowest Node version (v18)
• export NODE_OPTIONS=--openssl-legacy-provider in terminal
• npx expo install --fix this was a fresh project so there wasn't anything
• npx react-native start --reset-cache

[mayyamark]

Facing the same issue. I have tried with node 14, 16, 17, 18 and 20 without any luck..

[robhogan]

That error is a symptom rather than the cause. Bundler only assigns _transformer once the dependency graph is ready, and if that fails the constructor logs Failed to construct transformer: <error> and swallows it (#1854 should fix that) - so the next call fails with "Cannot read property 'transformFile' of undefined."

The real error should have been printed before this one, closer to the top of the logs when the transformer is first started.