@withStyles + required propType checks shows warning

not sure when this started happening but it wasnt happening before. when using decorators for withStyles and checking for the classes prop inside the class i get the following error

Warning: Failed prop type: The prop `classes` is marked as required in `withStyles(MyModule)`, but its value is `undefined`.

same explanation using code:

const styles = theme => (...)

// works and shows warning
@withStyles(styles)
export default class MyModule extends Component {
  static propTypes = {
    classes: PropTypes.object.isRequired,
  }
  ...
}

// works without warning
class MyModule extends Component {
  static propTypes = {
    classes: PropTypes.object.isRequired,
  }
  ...
}

export default withStyles(styles)(LoginModule)

[dskyberg]

Here are the relevant entries:

"babel": {
    "presets": [
        "@babel/preset-env",
        "@babel/preset-stage-0",
        "@babel/preset-react"
    ],
    "plugins": [
        "transform-decorators-legacy",
        "@babel/plugin-transform-runtime", [
            "@babel/plugin-proposal-class-properties",
            {
                "loose": true
            }
        ]
    ]
},
"dependencies": {
    "@babel/polyfill": "^7.0.0-beta.35",
    "@babel/runtime": "^7.0.0-beta.35"
},
"devDependencies": {
    "@babel/cli": "^7.0.0-beta.35",
    "@babel/core": "^7.0.0-beta.35",
    "@babel/plugin-transform-runtime": "^7.0.0-beta.35",
    "@babel/preset-env": "^7.0.0-beta.35",
    "@babel/preset-react": "^7.0.0-beta.35",
    "@babel/preset-stage-0": "^7.0.0-beta.35",
    "babel-eslint": "8.0.3",
    "babel-jest": "^22.0.3",
    "babel-loader": "^8.0.0-beta.0",
    "babel-plugin-transform-decorators-legacy": "^1.3.4"
}

[lmachens]

Looks like classes is undefined in constructor. So the decorator inject classes on mount.