Building JavaScript bundle often gets stuck at 0%

Description

When the Expo app starts and I click on my project, 1 out of every 3-4 times it gets stuck. This also happens with the same frequency when I have live reloading enabled and save my changes. The text at the bottom of the screen says “Building JavaScript Bundle…” and to the right is written 0.00%. When this happens, I have to restart the project from Expo XDE and shut down the app on my phone and restart it for it to work again.

Expected Behavior

When I reload the app after changing code, or when I start it up, it should finish building the javascript bundle and start my app.

Observed Behavior

The loading indicator gets stuck at 0%.

If there’s an error message, please paste the full terminal output and error message in this code block:

No error message. I can’t even shake the phone so I can get the developer tools.

Environment

Please run these commands in the project folder and fill in their results:

• npm ls react-native-scripts: It says empty.

• npm ls react-native:

UNMET DEPENDENCY react-native@https://github.com/expo/react-native/archive/sdk-23.0.1.tar.gz 

npm ERR! missing: react-native@https://github.com/expo/react-native/archive/sdk-23.0.1.tar.gz, required by MYAPPNAME@0.1.0
npm ERR! extraneous: react-native@https://github.com/expo/react-native/archive/sdk-23.0.1.tar.gz FOLDERPATH/app/node_modules/react-native

• npm ls expo:

UNMET DEPENDENCY expo@23.0.6 

npm ERR! missing: expo@23.0.6, required by MYAPPNAME@0.1.0
npm ERR! extraneous: expo@23.0.6 FOLDERPATH/app/node_modules/expo

• node -v: v8.7.0
• npm -v: 5.5.1
• yarn --version: 1.3.2
• watchman version: 4.9.0

Also specify:

1. Operating system: MacOS High Sierra 10.13.1
2. Phone/emulator/simulator & version: iPhone 6s

Here’s my package.json if that’s of any help.

{
  "name": "MYAPPNAME",
  "version": "0.1.0",
  "private": true,
  "devDependencies": {
    "babel-cli": "^6.26.0",
    "babel-jest": "^21.2.0",
    "babel-plugin-transform-react-jsx-source": "^6.22.0",
    "babel-preset-es2015": "^6.24.1",
    "babel-preset-react-native": "^4.0.0",
    "enzyme": "^3.2.0",
    "jest": "^21.2.1",
    "jest-expo": "^24.0.0",
    "prettier": "^1.7.4",
    "prettier-eslint": "^8.2.1",
    "react-native-scripts": "1.3.1",
    "react-test-renderer": "^16.0.0"
  },
  "main": "./node_modules/react-native-scripts/build/bin/crna-entry.js",
  "scripts": {
    "start": "react-native-scripts start",
    "eject": "react-native-scripts eject",
    "android": "react-native-scripts android",
    "ios": "react-native-scripts ios",
    "test": "jest"
  },
  "jest": {
    "preset": "jest-expo",
    "testPathIgnorePatterns": [
      "/node_modules/"
    ]
  },
  "dependencies": {
    "axios": "^0.16.2",
    "expo": "^24.0.0",
    "firebase": "^4.5.1",
    "lodash": "^4.17.4",
    "moment": "^2.19.1",
    "prop-types": "^15.6.0",
    "react": "16.0.0",
    "react-native": "https://github.com/expo/react-native/archive/sdk-24.0.0.tar.gz",
    "react-native-autocomplete-input": "^3.4.0",
    "react-native-azure-ad": "^0.2.4",
    "react-native-img-cache": "^1.5.3",
    "react-native-router-flux": "^4.0.0-beta.21",
    "react-native-slider": "^0.11.0",
    "react-redux": "^5.0.6",
    "redux": "^3.7.2",
    "redux-thunk": "^2.2.0",
    "watchman": "^1.0.0"
  }
}

[floriancargoet]

Just got this issue, I can’t build my JS bundle anymore. Deleting node_modules & package-lock.json did not help.

Edit: This stack overflow answer helped: https://stackoverflow.com/a/45477185/4829109 => Delete the content of /usr/local/var/run/watchman/

[bogomya]

There are some problems with watchman. But running watchman --foreground in a separate terminal solved the issue with stucked build for me.