[async] Cannot read property 'members' of undefined

[nippur72]

when compiling this code for ES5 (not ES6)

async function f() {
   return { };  
}

instead of giving the "only available in ES6" warning, it throws this exception:

               throw e;
                     ^
TypeError: Cannot read property 'members' of undefined
   at resolveDeclaredMembers (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:15429:65)
   at resolveTypeReferenceMembers (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:15459:26)
   at resolveStructuredTypeMembers (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:15665:21)
   at getPropertiesOfObjectType (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:15673:24)
   at propertiesRelatedTo (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:17141:34)
   at objectTypeRelatedTo (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:17107:30)
   at isRelatedTo (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:16935:34)
   at checkTypeRelatedTo (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:16824:26)
   at checkTypeAssignableTo (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:16797:20)
   at isTypeAssignableTo (C:\Users\Nino\AppData\Roaming\npm\node_modules\typescript\bin\tsc.js:16791:20)

using tsc 1.5.3

[rbuckton]

@nippur72: TypeScript 1.5.3 does not contain support for Async Functions, and I cannot seem to repro this in master. It's possible a recent unrelated change may have fixed this. Is it possible you were using a different version of the compiler than the one you mentioned above? Can you verify the version of the compiler you are using, or possibly verify this against a recent nightly build?

[mhegazy]

@nippur72 can you try using latest `typescript@next?

[nippur72]

@mhegazy @rbuckton I've checked with typescript@next and the bug is gone, so I'm closing this.

(P.S. I was sure it was 1.5.3, but as you've said it couldn't be, so more likely I had something greater than 1.5.3).

[mhegazy]

thanks @nippur72 for confirming.

[jsen-]

I think the issue is not yet gone.

I'm using typescript 1.6.0-dev.20150819 with experimentalAsyncFunctions enabled, targetting es6

The following code seems to trigger the error:

async function abcd() {
    console.log('abcd');
}
abcd().then(() => {
    console.log('then');
});

or

async function abcd() {
    console.log('abcd');
}
async function runAbcd() {
    await abcd();
}
runAbcd();

The following compiles (unfortunately there's no awaiting mechanism):

async function abcd() {
    console.log('abcd');
}
abcd();

D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:35252
                throw e;
                ^

TypeError: Cannot read property 'members' of undefined
    at resolveDeclaredMembers (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:15607:65)
    at resolveTypeReferenceMembers (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:15637:26)
    at resolveStructuredTypeMembers (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:15870:21)
    at getPropertyOfType (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:16002:32)
    at checkPropertyAccessExpressionOrQualifiedName (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:19993:24)
    at checkPropertyAccessExpression (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:19978:20)
    at checkExpressionWorker (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:22117:28)
    at checkExpression (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:22068:42)
    at resolveCallExpression (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:20919:28)
    at getResolvedSignature (D:\projects\sach\node_modules\electrolyte\node_modules\typescript\lib\typescript.js:21088:47)

iojs versions:

{ http_parser: '2.5.0',
  node: '3.0.0',
  v8: '4.4.63.26',
  uv: '1.6.1',
  zlib: '1.2.8',
  ares: '1.10.1-DEV',
  modules: '45',
  openssl: '1.0.2d' }

[nippur72]

Yes the issue is back, I re-discovered it yesterday in 1.6 nightly, so I'm reopening it.

[rbuckton]

This is now fixed for 1.6.