模块构建失败（来自 ./node_modules/babel-loader/lib/index.js）：错误：找不到模块“babel-preset-react”

Question

I'm stuck with the following error when trying to build a react app with Webpack4 and Babel7.

ERROR in ./src/index.js
Module build failed (from ./node_modules/babel-loader/lib/index.js):
Error: Cannot find module 'babel-preset-react' from '/Users/me/Desktop/reflask'
- If you want to resolve "react", use "module:react"
- Did you mean "@babel/react"?
    at Function.module.exports [as sync] (/Users/me/Desktop/reflask/node_modules/resolve/lib/sync.js:43:15)
    at resolveStandardizedName (/Users/me/Desktop/reflask/node_modules/@babel/core/lib/config/files/plugins.js:101:31)
    at resolvePreset (/Users/me/Desktop/reflask/node_modules/@babel/core/lib/config/files/plugins.js:58:10)
    at loadPreset (/Users/me/Desktop/reflask/node_modules/@babel/core/lib/config/files/plugins.js:77:20)
    at createDescriptor (/Users/me/Desktop/reflask/node_modules/@babel/core/lib/config/config-descriptors.js:154:9)
    at items.map (/Users/me/Desktop/reflask/node_modules/@babel/core/lib/config/config-descriptors.js:109:50)
    at Array.map (<anonymous>)
    at createDescriptors (/Users/me/Desktop/reflask/node_modules/@babel/core/lib/config/config-descriptors.js:109:29)
    at createPresetDescriptors (/Users/me/Desktop/reflask/node_modules/@babel/core/lib/config/config-descriptors.js:101:10)
    at passPerPreset (/Users/me/Desktop/reflask/node_modules/@babel/core/lib/config/config-descriptors.js:58:96)
 @ multi (webpack)-dev-server/client?http://localhost:8080 ./src main[1]

I've tried removing the node_modules folder and reinstalling dependencies with the following.

Terminal

rm -rf node_modules/
npm install

Configuration

package.json

{
  "name": "reflask",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "webpack-dev-server --open --mode development",
    "build": "webpack"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "@babel/core": "^7.1.0",
    "@babel/preset-env": "^7.1.0",
    "@babel/preset-react": "^7.0.0",
    "babel-loader": "^8.0.2",
    "html-loader": "^0.5.5",
    "html-webpack-plugin": "^3.2.0",
    "prop-types": "^15.6.2",
    "webpack": "^4.19.1",
    "webpack-cli": "^3.1.1",
    "webpack-dev-server": "^3.1.9"
  },
  "dependencies": {
    "bootstrap": "^4.1.3",
    "react": "^16.5.2",
    "react-bootstrap": "^0.32.4",
    "react-dom": "^16.5.2",
    "react-router-dom": "^4.3.1"
  }
}

webpack.config.js

const HtmlWebPackPlugin = require("html-webpack-plugin");
module.exports = {
    module: {
        rules: [
            {
                test: /\.js$/,
                exclude: /node_modules/,
                use: {
                    loader: "babel-loader",
                    options: {
                        presets: ['react']
                    }
                }
            },
            {
                test: /\.html$/,
                use: [
                    {
                        loader: "html-loader"
                    }
                ]
            }
        ]
    },
    plugins: [
        new HtmlWebPackPlugin({
            template: "./src/index.html",
            filename: "./index.html"
        })
    ]
};

index.js

import React from 'react';
import ReactDOM from 'react-dom';
import App from './js/components/App.jsx';
import registerServiceWorker from './registerServiceWorker';

ReactDOM.render(<App />, document.getElementById('root'));
registerServiceWorker();

.babelrc

{
  "presets": ["@babel/preset-env", "@babel/preset-react"]
}

Answer 1

in your webpack config did you already try @babel/preset-react instead of just react ?

Btw. you test for /\\.js$/ Better test for /\\.jsx?$/ (x? means x is optional), because you import a .jsx file in your index.js

Not

options: {
    presets: ['react']
}

but

options: {
    presets: ['@babel/preset-react']
}

Answer 2

place .babelrc file at root dir with this inside

{
  "presets": ["@babel/preset-env", "@babel/preset-react"]
}

and remove preset from babel-loader webpack cfg

options: {
  presets: ['react']
}

Answer 3

I did it at the end with this settings, (becouse es2015 has been changed https://www.npmjs.com/package/babel-preset-es2015 ) now!

And presets in package.json or .babelrc or babel.config ::

 use: { loader: 'babel-loader', options: { presets: ['@babel/react', '@babel/preset-env'], plugins: ['@babel/plugin-proposal-class-properties'] } }

and..

 "devDependencies": { "@babel/cli": "^7.1.5", "@babel/core": "^7.1.6", "@babel/plugin-proposal-class-properties": "^7.1.0", "@babel/plugin-transform-react-constant-elements": "^7.0.0", "@babel/plugin-transform-react-inline-elements": "^7.0.0", "@babel/preset-env": "^7.1.6", "@babel/preset-react": "^7.0.0", "@babel/register": "^7.0.0", "@babel/runtime": "^7.1.5", "babel-eslint": "^8.2.6", "babel-loader": "^8.0.4", "babel-node": "^6.5.3", "babel-plugin-react-transform": "^3.0.0", "babel-plugin-transform-class-properties": "^6.24.1", "babel-plugin-transform-react-pure-class-to-function": "^1.0.1", "babel-plugin-transform-react-remove-prop-types": "^0.4.20", "babel-polyfill": "^6.26.0", "babel-preset-env": "^1.7.0", "babel-preset-es2015": "^6.24.1", "babel-preset-react": "^6.24.1", "webpack": "^4.26.1" }

and the code that you call to preset example:

   "theme:build": "babel theme/src -d theme/dist --presets @babel/react --plugins transform-class-properties --quiet && npm run webpack:store",

presets @babel/react

in github very much forum about the subject!

Answer 4

I had the same error before, I just run the app on another port.

To do so run this command in ur terminal

npm start

Then it'll ask if u want to run the app on another port write

y

Answer 5

It worked for me, I had to change ['react'] to ['@babel/preset-react'] in .bablerc
If your are upgrading babel from 6.x to 7.x