React-native: New project with typescript template causes Haste module naming collision error

[stefanedberg]

When creating a new React Native project with typescript template the following error occurs:

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└──────────────────────────────────────────────────────────────────────────────┘

Looking for JS files in
   /Users/user/development/ProjectName 

Loading dependency graph...jest-haste-map: Haste module naming collision: ProjectName
  The following files share their name; please adjust your hasteImpl:
    * <rootDir>/package.json
    * <rootDir>/template/package.json

Failed to construct transformer:  { Error: Duplicated files or mocks. Please check the console for more info
    at setModule (/Users/user/development/ProjectName/node_modules/jest-haste-map/build/index.js:620:17)
    at workerReply (/Users/user/development/ProjectName/node_modules/jest-haste-map/build/index.js:691:9)
    at process._tickCallback (internal/process/next_tick.js:68:7)
  mockPath1: 'package.json',
  mockPath2: 'template/package.json' }
(node:4451) UnhandledPromiseRejectionWarning: Error: Duplicated files or mocks. Please check the console for more info
    at setModule (/Users/user/development/ProjectName/node_modules/jest-haste-map/build/index.js:620:17)
    at workerReply (/Users/user/development/ProjectName/node_modules/jest-haste-map/build/index.js:691:9)
    at process._tickCallback (internal/process/next_tick.js:68:7)
(node:4451) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:4451) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
Error: Duplicated files or mocks. Please check the console for more info
    at setModule (/Users/user/development/ProjectName/node_modules/jest-haste-map/build/index.js:620:17)
    at workerReply (/Users/user/development/ProjectName/node_modules/jest-haste-map/build/index.js:691:9)
    at process._tickCallback (internal/process/next_tick.js:68:7)

React Native version:
System: OS: macOS 10.14.6 CPU: (8) x64 Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz Memory: 530.60 MB / 16.00 GB Shell: 3.2.57 - /bin/bash Binaries: Node: 10.16.3 - /usr/local/bin/node Yarn: 1.5.1 - /usr/local/bin/yarn npm: 6.9.0 - /usr/local/bin/npm Watchman: 4.9.0 - /usr/local/bin/watchman SDKs: iOS SDK: Platforms: iOS 12.4, macOS 10.14, tvOS 12.4, watchOS 5.3 Android SDK: API Levels: 22, 23, 25, 26, 27, 28 Build Tools: 23.0.1, 25.0.0, 25.0.1, 25.0.2, 25.0.3, 26.0.2, 27.0.3, 28.0.3 System Images: android-22 | Intel x86 Atom, android-22 | Intel x86 Atom_64, android-22 | Google APIs Intel x86 Atom_64, android-23 | Intel x86 Atom, android-23 | Intel x86 Atom_64, android-23 | Google APIs Intel x86 Atom, android-24 | Google Play Intel x86 Atom, android-25 | Google APIs Intel x86 Atom, android-26 | Android TV Intel x86 Atom, android-26 | Android Wear Intel x86 Atom, android-26 | Google APIs Intel x86 Atom, android-26 | Google Play Intel x86 Atom Android NDK: 16.1.4479499 IDEs: Android Studio: 3.1 AI-173.4697961 Xcode: 10.3/10G8 - /usr/bin/xcodebuild npmPackages: react: 16.8.6 => 16.8.6 react-native: 0.60.5 => 0.60.5 npmGlobalPackages: create-react-native-app: 1.0.0 react-native-app-id: 0.0.4 react-native-cli: 2.0.1 react-native-git-upgrade: 0.2.7

Steps To Reproduce

1. react-native init ProjectName --template typescript
2. cd ProjectName && react-native run-ios

Describe what you expected to happen:
The development server should start and the app would run successfully.

[lordkiz]

There appears to be a package.json file in both ./rootAppFolder and ./rootAppFolder/template. I wonder if the default file structure should be so.

[kristianhasselknippe]

Removing the template folder fixed the issue for me. Thanks for the hint @lordkiz

[lordkiz]

@kristianhasselknippe if you still want to use typescript after removing the template folder, just follow the instructions on https://github.com/Microsoft/TypeScript-React-Native-Starter

[ycai2]

I'm facing the same issue. The above solution definitely will work, but it feels wrong...
Isn't the whole point of init --template typescript to have a typescript RN project without any manual installation? Just removing the template folder and manually install typescript would defeat the purpose of --template config, no? ... Does this mean that template support is being dropped?
If it were just a bug, it'd all make sense though.

[larkintuckerllc]

FYI... Just over a month ago, I used the documented --template typescript approach and got a fully operational solution. Used as a baseline for an article that I wrote about adding ESLint for linting.

Happened to notice today that the exact same command produces a completely different project.

Here is the repository, with the Baseline commit being what was generated by the command at the time.

https://github.com/larkintuckerllc/ESLintReactNative/tree/60c1ffc99be6485a6dfb55971c3c2dd93a6af861

[ycai2]

@stefanedberg I also found https://github.com/react-native-community/react-native-template-typescript/issues/64. Don't if it's related or whether it could help.
It seems somehow you have to npm uninstall react-native-cli first, as an IMPORTANT STEP.

[larkintuckerllc]

FYI.. Confirmed that the updated command of:

npx react-native init [YOUR PROJECT] --template react-native-template-typescript

starts up an entirely different looking installer (blue logo, etc). Also looks like you have to refer to the template directly (not just typescript).

[alradadi]

npm uninstall -g react-native-cli
npx react-native init MyApp --template react-native-template-typescript

This worked for me.

[andytrich]

I was caught out by this too. abdullah-sr soloution worked for me.

The CLI git hub page recommends using the local command npx react-native init MyApp --template react-native-template-typescript rather than the global react-native init MyApp --template typescript

We strongly encourage you to only use global react-native-cli for bootstrapping new projects. Use local version for everything else.

To be fair even the getting started documentation is lagging behind https://facebook.github.io/react-native/docs/typescript

[cargallo]

It seems that people behind react native strives the community to move to flutter platform. Lately coding on this is a hell of warnings, deprecations and this kind of problems where something that works a month ago, suddenly stops working with no reasonable cause

[stale[bot]]

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[stale[bot]]

Closing this issue after a prolonged period of inactivity. If this issue is still present in the latest release, please feel free to create a new issue with up-to-date information.