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This repository was archived by the owner on Jan 26, 2019. It is now read-only.
This repository was archived by the owner on Jan 26, 2019. It is now read-only.

key on React Component does not compile #300

Closed
@jlguenego

Description

@jlguenego

Is this a bug report?

Yes

Can you also reproduce the problem with npm 4.x?

Yes

Which terms did you search for in User Guide?

key
Module build failed: TypeError: Cannot read property 'length' of undefined

Environment

D:\repos\zzz_react_ts>npm ls react-scripts-ts
zzz_react_ts@0.1.0 D:\repos\zzz_react_ts
`-- react-scripts-ts@2.14.0

D:\repos\zzz_react_ts>node -v
v9.4.0

D:\repos\zzz_react_ts>npm -v
4.6.1

Then, specify:

  1. Operating system: Windows 10
  2. Browser and version (if relevant):
    Chrome 65

Steps to Reproduce

npm install -g create-react-app
create-react-app zzz --scripts-version=react-scripts-ts
cd zzz
npm start

(Write your steps here:)

  1. Replace App.tsx with the following content:
import * as React from 'react';
import './App.css';

const MyComp = () => <div>bar</div>;

class App extends React.Component {
  render() {
    return (
      <div>
        {[0, 1, 2].map(n => <MyComp key={n}/>)}
      </div>
    );
  }
}

export default App;

Expected Behavior

You should see no error in the browser, and a loop printed.

Actual Behavior

Error in the browser:
./src/App.tsx
Module build failed: TypeError: Cannot read property 'length' of undefined

The bug is on MyComp key={n}

Reproducible Demo

zzz_react_ts.zip

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