React npm start tidak berfungsi setelah create-react-app

Sep 16 2020

Saya hanya belajar React dan bahasa Inggris saya buruk. Saya sudah memiliki dua proyek reaksi tetapi mereka juga tidak berhasil :( Saya mengikuti langkah-langkah ini,

npx buat-reaksi-aplikasi aplikasi-saya cd aplikasi-saya npm start

tapi tidak berhasil. Saya mencoba membersihkan cache dan menginstal npm lagi tetapi tidak berhasil. Bagaimana saya bisa memecahkan masalah ini?

> [email protected] start /Users/edu/Documents/htdocs/my-app
> react-scripts start


There might be a problem with the project dependency tree.
It is likely not a bug in Create React App, but something you need to fix locally.

The react-scripts package provided by Create React App requires a dependency:

  "babel-loader": "8.0.5"

Don't try to install it manually: your package manager does it automatically.
However, a different version of babel-loader was detected higher up in the tree:

  /Users/edu/node_modules/babel-loader (version: 8.1.0) 

Manually installing incompatible versions is known to cause hard-to-debug issues.

If you would prefer to ignore this check, add SKIP_PREFLIGHT_CHECK=true to an .env file in your project.
That will permanently disable this message but you might encounter other issues.

To fix the dependency tree, try following the steps below in the exact order:

  1. Delete package-lock.json (not package.json!) and/or yarn.lock in your project folder.
  2. Delete node_modules in your project folder.
  3. Remove "babel-loader" from dependencies and/or devDependencies in the package.json file in your project folder.
  4. Run npm install or yarn, depending on the package manager you use.

In most cases, this should be enough to fix the problem.
If this has not helped, there are a few other things you can try:

  5. If you used npm, install yarn (http://yarnpkg.com/) and repeat the above steps with it instead.
     This may help because npm has known issues with package hoisting which may get resolved in future versions.

  6. Check if /Users/edu/node_modules/babel-loader is outside your project directory.
     For example, you might have accidentally installed something in your home folder.

  7. Try running npm ls babel-loader in your project folder.
     This will tell you which other package (apart from the expected react-scripts) installed babel-loader.

If nothing else helps, add SKIP_PREFLIGHT_CHECK=true to an .env file in your project.
That would permanently disable this preflight check in case you want to proceed anyway.

P.S. We know this message is long but please read the steps above :-) We hope you find them helpful!

npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] start: `react-scripts start`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the [email protected] start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /Users/edu/.npm/_logs/2020-09-17T00_43_20_777Z-debug.log

Jawaban

2 ScottyJamison Sep 17 2020 at 00:50

Lihatlah saran nomor 6 di keluaran Anda.

Periksa apakah / Users / edu / node_modules / babel-loader berada di luar direktori proyek Anda. Misalnya, Anda mungkin tidak sengaja menginstal sesuatu di folder utama Anda.

Kedengarannya seperti di beberapa titik Anda secara tidak sengaja menginstal npm di folder home Anda ( /Users/edu/) alih-alih folder proyek Anda, dan proyek Anda mengambil ketergantungan ini.

Perbaikannya adalah menghapus node_modules, package.json, dan package-lock.json /Users/edu/, yang tidak perlu ada di sana.

fedeteka Sep 16 2020 at 23:51

Mungkin mencoba:

npm cache clean

npm install

npm create-react-app my-app

cd my-app

npm run start