问题
I was trying to run webpack-4 first time
webpack ./src/js/app.js ./dist/app.bundle.js
it shows warning / error :
WARNING in configuration
The 'mode' option has not been set, webpack will fallback to 'production' for this value. Set 'mode' option to 'development' or 'production' to enable defaults for each environment.
You can also set it to 'none' to disable any default behavior. Learn more: https://webpack.js.org/concepts/mode/
ERROR in multi ./src/js/app.js ./dist/app.bundle.js
Module not found: Error: Can't resolve './dist/app.bundle.js' in 'D:\wamp64\www\webpack-4'
@ multi ./src/js/app.js ./dist/app.bundle.js
Then i tried to change the mode
webpack --mode development
it shows :
ERROR in Entry module not found: Error: Can't resolve './src'
回答1:
Resolved
Spent a lot of time to find out the solution.
Solution: Add index.js file into src folder.
That's it!.. solved :)
During Research, I found some facts about webpack 4 :
webpack 4 doesn’t need a configuration file by default!
webpack 4 there is no need to define the entry point: it will take ./src/index.js as the default!
回答2:
Met this problem when deploying on now.sh
Solution: Use Default Behavior
Move entry point to src/index.js.
This leverage webpack@4 default value for entry:
By default its value is
./src/index.js, but you can specify a different (or multiple entry points) by configuring the entry property in the webpack configuration.
Solution: Be Specific
As @Lokeh pointed out, if you don't want to change your JS file location you can always use path.resolve() in your webpack.config.js:
entry: path.resolve(__dirname, 'src') + '/path/to/your/file.js',
回答3:
webpack ./src/js/app.js --output ./dist/app.bundle.js --mode development
This worked for me. I had the same trouble, it is because of a new version of webpack
回答4:
As of webpack ^4.29.6 you don't need any configuration file so instead of giving path in package.json we need to write simply "build": "webpack" and keep index.js as entry point in src folder. However if you want to change entry point you can do so in webpack config file
来源：https://stackoverflow.com/questions/49772863/webpack-4-error-in-entry-module-not-found-error-cant-resolve-src