`observer(component)` is not correctly recognized by typescript 1.8-beta about mobx-react HOT 5 CLOSED

I have a similar issue. When I write the following (valid) code:

const ObservedMyComponent = observer(MyComponent);
createElement(ObservedMyComponent, { key: "12" });

I get the following error on the second line:

error TS2345: Argument of type 'ComponentClass<any> | void' is not assignable to parameter of type 'ComponentClass<any> | StatelessComponent<any>'.
  Type 'void' is not assignable to type 'ComponentClass<any> | StatelessComponent<any>'.
    Type 'void' is not assignable to type 'StatelessComponent<any>'.

After some juggling around, I've figured out that the problem is in the following line in your package typings:

export function observer<TFunction extends React.ComponentClass<any>>(target: TFunction): TFunction | void; // decorator signature

If you remove the void case, everything works as expected.

Typescript 1.7.5, React 0.14

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I tried to reproduce this issue (see the above commit), however the above error didn't occur.

Does the test https://github.com/mweststrate/mobservable-react/blob/master/test/ts/compile-ts.tsx properly reproduce the issue? Feel free to amend.

Test can simply be run by cloning the repo and running tsc -p test/ts

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Maybe a different version of react.d.ts?

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Didn't have a time to double check it yet, but your tests are missing the case where I got an error:

class T7 extends Component<{ pizza: number}, {}> {
    render() {
        return <div>{this.props.pizza}</div>;
    }
}
React.createElement(observer(T7), { pizza: "4 seasons" });

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Tnx. That was the culprit indeed! Fixed and released as 2.1.5

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