decorators on generator functions parse error with --typescript

[wangtao0101]

Is this a bug report?

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Yes

Did you try recovering your dependencies?

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npm --version
6.4.1

Which terms did you search for in User Guide?

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decorators on generator functions parse error with --typescript

Environment

(paste the output of the command here)

Environment Info:

System:
OS: Windows 10
CPU: x64 Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz
Binaries:
Yarn: 1.10.1 - C:\Program Files\nodejs\yarn.CMD
npm: 6.1.0 - C:\Program Files\nodejs\npm.CMD
Browsers:
Edge: 42.17134.1.0
Internet Explorer: 11.0.17134.1
npmPackages:
react: ^16.8.4 => 16.8.4
react-dom: ^16.8.4 => 16.8.4
react-scripts: Not Found
npmGlobalPackages:
create-react-app: Not Found

Steps to Reproduce

(Write your steps here:)

1. create-react-app my-app typescript
2. add experimentalDecorators in tsconfig.json
3. add related code

@effect() // define async action handle
    * addAsync(count: number) {
        yield delay(2000);
        this.add(count); // type check here
    }

Expected Behavior

(Write what you thought would happen.)

parse success

Actual Behavior

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./src/AppModel.ts
SyntaxError: C:\Users\zeroone\Desktop\my-app\src\AppModel.ts: Unexpected token (17:30)

  15 | export default class AppModel extends Model<AppState> {
  16 |     @effect() // define async action handle
> 17 |     * addAsync(count: number) {
     |                               ^
  18 |         yield delay(2000);
  19 |         this.add(count); // type check here
  20 |     }

Reproducible Demo

(Paste the link to an example project and exact instructions to reproduce the issue.)

[mrmckeb]

Hi @wangtao0101, I believe this is related to #6225.

If so, it looks like this was just solved on the Babel side and we'll be able to fix this by bumping our dependencies. babel/babel#9693

Would you like to submit a PR for that?

[wangtao0101]

@mrmckeb after i try @babel/plugin-transform-typescript@7.4.0, the bug was still, but i agree that maybe the bug do caused by babel