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

在使用Webpack4和Babel7构建React应用时，我遇到了以下错误。

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]

我尝试过使用以下命令删除 node_modules 文件夹并重新安装依赖项。

终端

rm -rf node_modules/
npm install

配置

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

：Babel配置文件。

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

- user3342735

Answer 1

在你的Webpack配置中，你是否已经尝试过使用@babel/preset-react而不仅仅是react？

顺便提一下，你测试了/\.js$/，最好测试/\.jsx?$/（x? 表示 x 是可选的），因为你在 index.js 中导入了一个 .jsx 文件。

不要这样做。

options: {
    presets: ['react']
}

但是

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

- Matthi

Answer 2

将 .babelrc 文件放在根目录，并按如下内容编写：

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

从babel-loader webpack配置中移除预设

options: {
  presets: ['react']
}

- zebnat

---

抱歉，我应该提到 .babelrc 文件已经在根目录中，并且包含了您上面所述的内容。此外，我添加了 presets: ['react'] 部分，因为我在 ./src/js/components/App.jsx 中遇到了一个错误 'Module parse failed: Unexpected token'，这个文件中引用了一些 HTML。 - user3342735

webpack的预设选项是babelrc的替代品。 - zebnat

正如zebnat所说，webpack的preset选项是babelrc的一个完全可行的替代品。任何有助于开发人员合并配置文件的工具都应该被鼓励使用。 - stackleit

Answer 3

我使用这个设置最终完成了它，（因为es2015已经改变 https://www.npmjs.com/package/babel-preset-es2015）。

在package.json或.babelrc或babel.config中的预设：

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

和..

"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"
  }

并且你调用的代码来预设示例：

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

预设 @babel/react

在 Github 上有很多关于此主题的论坛！

- Hamit YILDIRIM

---

持续遇到旧仓库错误，其babel依赖项未更新完成且webpack 4设置不太好。第一部分对我有效，已按上述更改了我的webpack。 - Carmine Tambascia

Answer 4

这对我有用，我不得不在 .bablerc 中将 ['react'] 更改为 ['@babel/preset-react']。
如果你正在从 babel 6.x 升级到 7.x

- ashish siddhu

---

最好发布文件中的实际代码，而不是屏幕截图。 - Guillermo Aguirre

Answer 5

如果你正在将 Babel 从 6.x 升级到 7.x，这个方法对我有效。我需要在 .bablerc 文件中进行以下更改：

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

- Abhishek Verma

Answer 6

我之前也遇到了同样的错误，我只是在另一个端口上运行了应用程序。

为此，在终端中运行以下命令：

npm start

然后它会询问您是否要在另一个端口上运行应用程序，请输入：

y

- LaLa