The CLI moved into a separate package: webpack-cli
I went through the same example and faced the same issue. So following the above answers I first ran this command -
npm install -g webpack-cli --save-devNothing happened and was still facing the same issue.
Then I ran this command -
npm install webpack-cli --save-devThe issue was solved but I was getting another error.
Turns out in the new Webpack version they have changed the module attributes also. So you need to make change in the webpack.config.js file also.
module: { rules: [ { test: /\.jsx?$/, exclude: /node_modules/, loader: 'babel-loader', query: { presets: ['es2015', 'react'] } } ] }So basically loaders is replaced by rules inside the module object.
I made this change and it worked for me.
Hope it helps other people who are following this tutorial.
To resolve the Invalid configuration object issue, I referred to this answer.https://stackoverflow.com/a/42482079/5892553
In webpack 3, webpack itself and the CLI for it used to be in the same package, but in version 4, they've separated the two to manage each of them better.
To solve your issue, install the webpack-cli package as the error suggests by running npm install webpack-cli --save-dev on the command line, same as you would any other package.
Was having the same problem, and no luck with the above solutions - I tried installing webpack-cli globally as well as locally and this worked.
npm install -g webpack-cli --save-devThis fixed it for me. At least enough to perform webpack --mode development.