WebStorm type checking React props using type definition

Question

I'm using WebStorm 2018.3.4 and am trying to figure out how to do type checking on a React component's props. Specifically, if a prop is marked as a string but I give it a number I want WebStorm to show an error. I've created a type definition file (as described here ). Here's what the file looks like:

MyComponent.d.ts

import * as React from 'react';

export interface MyComponentProps {
  /** this is the component's title */
  title: string;

  /** this is a short description of the component */
  description?: string;
}

declare class MyComponent extends React.Component<MyComponentProps, {}> {
  render(): JSX.Element;
}

export default MyComponent;

App.jsx

class App extends React.Component {
  render() {
    return (
      <MyComponent title={7} />
    );
  }
}

I was hoping WebStorm would underline title={7} telling me that 7 is the wrong type. If I Ctrl+Q on the prop it definitely tells me the type is string and it gives me the documentation from the .d.ts file. Is there a setting I need to enable? Or does WebStorm not support this? Or is my problem that my app is using JSX rather than TypeScript? Any help would be appreciated.

Answer 1

You can install prop-types

Then you can write your component like this:

import React, { Component } from 'react';
import PropTypes from 'prop-types';

class App extends Component {
    static propTypes = {
        userId: PropTypes.string.isRequired,
        someObject: PropTypes.object.isRequired,
        someFunction: PropTypes.func.isRequired,
    };

    render() {
       ....
    }
}