importHelpers in tsconfig.json

[kwonoj]

Issue description or question

If tsconfig.json have config around helper functions,

   "importHelpers": true,
    "noEmitHelpers": true,

it seems noEmitHelpers are honored but importHelpers are not, so some of downlevel transpiled helper is not being referenced. Not sure if this specific configuration related or default behavior.

Sample code

//import 'tslib' //if explicitly imports, below works
const a = () => Promise.resolve('a');
(async() => console.log(await a()))();

tsconfif

{
  "compilerOptions": {
    "removeComments": false,
    "preserveConstEnums": true,
    "sourceMap": true,
    "allowJs": true,
    "noImplicitAny": true,
    "noImplicitReturns": true,
    "suppressImplicitAnyIndexErrors": true,
    "strictNullChecks": true,
    "noUnusedLocals": true,
    "noImplicitThis": true,
    "noUnusedParameters": true,
    "importHelpers": true,
    "noEmitHelpers": true,
    "module": "commonjs",
    "moduleResolution": "node",
    "target": "es2016",
    "jsx": "react",
    "outDir": ".tmp/build",
    "lib": [
      "es2016",
      "dom"
    ],
    "typeRoots": [
      "./node_modules/@types"
    ]
  },
  "include": [
    "src/**/*",
    "build/**/*",
    "spec/**/*"
  ],
}

Sample repository link

If the issue can not be reproduced just using the quokka file above
(for example because it requires/imports some files from your project),
please create a small repository where the issue can be reproduced.

Quokka.js Console Output

​​__awaiter is not defined​​
  at ​​​__dirname​​​ ​quokka.ts:2:12​
  at ​quokka.ts:2:12​

Code editor version

[x] Visual Studio Code v1.?
Webstorm v?
Atom v1.?

OS name and version

[x] Windows
OSX
Linux

[ArtemGovorov]

I didn't have a chance to fully investigate why it's happening, but the issue doesn't see to be Quokka specific. If I run tsc with your tsconfig file on your source file, I'm getting this output:

const a = () => Promise.resolve('a');
(() => __awaiter(this, void 0, void 0, function* () { return console.log(yield a()); }))();
//# sourceMappingURL=test.js.map

[ArtemGovorov]

Have done some investigation - this is by design in TypeScript:

If the file does not have a toplevel import/export is it is not considered a module, and it is treated as script/global.

So TypeScript expects these globals for the file because the file does not look like a module to it.

If you import/export into/from the file, it'll start working as expected:

import 'path';
const a = () => Promise.resolve('a');
(async() => console.log(await a()))();

or

const a = () => Promise.resolve('a');
(async() => console.log(await a()))();
export {};

[davvit]

@ArtemGovorov seems like what you found out does not help. I still get the error.

I am testing out async methods and when i call my long1() method i get the same error.

async function long1(): Promise<any> { return await new Promise((resolve) => { setTimeout(resolve, 500); console.log('long1 done'); return 1 }); }

[ArtemGovorov]

@davvit Could you please

• share your tsconfig.json file,
• on a simple file like this:

import 'path';
const a = () => Promise.resolve('a');
(async() => console.log(await a()))();

run Quokka, and then run Quokka.js: Show Instrumented Code command and paste the output from the Quokka console?