Typescript React component type mismatch

Question

Getting a typescript error when defining any type of simple react functional component with any number of props, including using FC, ComponentWithChildren etc...

Here's a minimal reproduction

type Props = {
  className?: string;
};

const Horizontal: Props = ({ className = undefined }) => (
  <div />
);

Gives me the error

Type '({ className }: { className?: undefined; }) => Element' has no properties in common with type 'Props'.ts(2559)

I don't understand this is how i always defined components. Is there something new in typescript that i don't know about?

{
  "name": "call-mvp",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "@testing-library/jest-dom": "^5.16.4",
    "@testing-library/react": "^13.2.0",
    "@testing-library/user-event": "^13.5.0",
    "@types/classnames": "^2.3.1",
    "@types/jest": "^27.5.1",
    "@types/node": "^16.11.36",
    "@types/react": "^18.0.9",
    "@types/react-dom": "^18.0.4",
    "@types/react-measure": "^2.0.8",
    "@types/react-router-dom": "^5.3.3",
    "@types/styled-components": "^5.1.25",
    "classnames": "^2.3.1",
    "react": "^18.1.0",
    "react-dom": "^18.1.0",
    "react-measure": "^2.5.2",
    "react-router-dom": "^6.3.0",
    "react-scripts": "5.0.1",
    "styled-components": "^5.3.5",
    "typescript": "^4.6.4",
    "web-vitals": "^2.1.4"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build",
    "test": "react-scripts test",
    "eject": "react-scripts eject"
  },
  "eslintConfig": {
    "extends": [
      "react-app",
      "react-app/jest"
    ]
  },
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  }
}

Yasin Br · Accepted Answer · 2022-05-20 21:37:12Z

1

you can change it to:

const Horizontal: FC = ({ className = undefined } : Props)

answered May 20, 2022 at 21:37

Yasin Br

1,8091 gold badge8 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

SFournier · Accepted Answer · 2022-05-20 21:34:10Z

1

This should work :

const Horizontal = ({ className = undefined } : Props) => ....

answered May 20, 2022 at 21:34

SFournier

664 bronze badges

2 Comments

Bolza Over a year ago

Ok weird, but what has changed compared to before? I have old code that worked fine with that definition

SFournier Over a year ago

Perhaps the definition has changed overtime. I know i've always use this syntax so it would be hard for me to say what change in a older version

Collectives™ on Stack Overflow

Typescript React component type mismatch

2 Answers 2

Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related