Webpack.js.org: [email protected]: unrecognized output.ecmaVersion option

[homobel]

Bug report

Doc says(https://webpack.js.org/migrate/5/) there is _output.ecmaVersion_ option to make webpack use es5 runtime.

What is the current behavior?

But when I use it I got validation error:

ValidationError: Invalid configuration object. Webpack has been initialized using a configuration object that does not match the API schema.
 - configuration.output has an unknown property 'ecmaVersion'. These properties are valid:

If the current behavior is a bug, please provide the steps to reproduce.

npm i webpack@next webpack-cli

webpack.config.js

module.exports = {
    mode: 'development',
    entry: './in.js',
    output: {
        ecmaVersion: 5
    }
};

in.js may be empty.

npx webpack

What is the expected behavior?
No validation error expected. Build runtime has es5 version(no array functions etc).

Other relevant information:
webpack version: 5.0.0-rc.3
Node.js version: v14.10.1
Operating System: win10 64

[yairza]

in https://github.com/webpack/webpack/releases under v5.0.0-beta.30 it says : "output.ecmaVersion is replaced with output.environment which lists features used by webpack"
However i could not find any documentation for output.environment

[homobel]

At least validation error for environment helps here :)

 - configuration.output.environment should be an object:
   object { arrowFunction?, bigIntLiteral?, const?, destructuring?, dynamicImport?, forOf?, module? }

[yairza]

on https://github.com/webpack/webpack/releases/tag/v5.0.0-rc.1 : "uses target: "browserslist" as default when a browserslist config has been found, otherwise fallback to target: "web" as usual"

So i tried to remove "targets" from babel.presets, and add browserslist instead, as below, but i dont see any change
` "browserslist": [
"Chrome >= 70",
"FireFox >= 52",
"Safari >= 10",
"IE 11",
"last 4 Edge versions"
],
"babel": {
"presets": [
[
"@babel/preset-env",
{

      "useBuiltIns": "usage",
      "corejs": {
        "version": 3,
        "proposals": true
      },
      "debug": true
    }
  ]
],`

[homobel]

So, probably should be converted to docs issue.

[alexander-akait]

Please use target: ['web', 'es5'], we need to update docs ASAP

[alexander-akait]

/cc @webpack/documentation-team need to solve ASAP

[alexander-akait]

Close in favor https://github.com/webpack/webpack.js.org/issues/4012