webpack can't find module if file named jsx

2019-01-07 11:13发布

问题:

As I write webpack.config.js like this

module.exports = {
  entry: './index.jsx',
  output: {
    filename: 'bundle.js'
  },
  module: {
    loaders: [{
      test: /\.jsx?$/,
      exclude: /node_modules/,
      loader: 'babel',
      query: {
        presets: ['es2015', 'react']
      }
    }]
  }
};

And in index.jsx I import a react module App

import React from 'react';
import { render } from 'react-dom';

import App from './containers/App';

let rootElement = document.getElementById('box')
render(
  <App />,
  rootElement
)

I find if I named module app in App.jsx, then webpack will say in index.jsx can't find module App, but if I named named module app in App.js, it will find this module and work well.

So, I'm confuse about it. In my webpack.config.js, I have writed test: /\.jsx?$/ to check file, but why named *.jsx can't be found?

回答1:

Webpack doesn't know to resolve .jsx files implicitly. You can specify a file extension in your app (import App from './containers/App.jsx';). Your current loader test says to use the babel loader when you explicitly import a file with the jsx extension.

or, you can include .jsx in the extensions that webpack should resolve without explicit declaration:

module.exports = {
  entry: './index.jsx',
  output: {
    filename: 'bundle.js'
  },
  module: {
    loaders: [{
      test: /\.jsx?$/,
      exclude: /node_modules/,
      loader: 'babel',
      query: {
        presets: ['es2015', 'react']
      }
    }]
  },
  resolve: {
    extensions: ['', '.js', '.jsx'],
  }
};

For Webpack 2, leave off the empty extension.

resolve: {
  extensions: ['.js', '.jsx']
}


回答2:

Adding to the above answer,

The resolve property is where you have to add all the file types you are using in your application.

Suppose you want to use .jsx or .es6 files; you can happily include them here and webpack will resolve them:

resolve: {
  extensions: ["", ".js", ".jsx", ".es6"]
}

If you add the extensions in the resolve property, you can remove them from the import statement:

import Hello from './hello'; // Extensions removed
import World from './world';

Other scenarios like if you want coffee script to be detected you should configure your test property as well like:

// webpack.config.js
module.exports = {
  entry: './main.js',
  output: {
    filename: 'bundle.js'       
  },
  module: {
    loaders: [
      { test: /\.coffee$/, loader: 'coffee-loader' },
      {
        test: /\.js$/,
        loader: 'babel-loader',
        query: {
          presets: ['es2015', 'react']
        }
      }
    ]
  },
  resolve: {
    // you can now require('file') instead of require('file.coffee')
    extensions: ['', '.js', '.json', '.coffee'] 
  }
};


回答3:

In the interest of readability and copy-paste coding. Here is the webpack 4 answer from mr rogers comment in this thread.

module: {
  rules: [
    {
      test: /\.(js|jsx)$/,
      exclude: /node_modules/,
      resolve: {
        extensions: [".js", ".jsx"]
      },
      use: {
        loader: "babel-loader"
      }
    },
  ]
}


回答4:

Verify, that bundle.js is being generated without errors (check the Task Runner Log).

I was getting 'can't find module if file named jsx' due to the syntax error in html in component render function.



回答5:

I was facing similar issue, and was able to resolve using resolve property.

const path = require('path');
module.exports = {
    entry: './src/app.jsx',
    output: {
        path: path.join(__dirname,'public'),
        filename:  'bundle.js'
    },
    module : {
        rules: [{
            loader: 'babel-loader',
            test: /\.jsx$/,
            exclude: /node_modules/
        }]
    },
    resolve: {
        extensions: ['.js', '.jsx']
    }
}

As You can see I have used .jsx in there which resolved following error

ERROR in ./src/app.jsx Module not found: Error: Can't resolve

For Reference: https://webpack.js.org/configuration/resolve/#resolve-extensions