__awaiter is not defined

[tinganho]

Was there something changed recently on the async/await for typescript? I'm using typescript@next to compile my project.

With below version it works fine:

$ tsc --version
Version 1.8.0-dev.20151210

But for this version it doesn't:

$ tsc --version
Version 1.8.0-dev.20151216

I got a runtime error:

ReferenceError: __awaiter is not defined

And in my code I have a bunch of object literals that has async functions:

let a: {
  f: async () => { ... }
}

I'm targetting es6. Though I cannot produce a self-contained test. Even though I compile the whole file excluding dependecies it includes the __awaiter. Only when I compile the whole project, just one file misses to have __awaiter on top of the file.

There must have been some very recent change. Since my CI started to bark today.

[DanielRosenwasser]

@rbuckton any clue?

[DanielRosenwasser]

@tinganho looks like you have a typo - did you mean

let a = {
  f: async () => { /*...*/ }
}

I get an awaiter here.

[rbuckton]

@tinganho I am also unable to reproduce this issue. We recently fixed an issue where __awaiter was added to the top of every file following a file with an async function, even when those files did not contain an async function. Could it be that the file in question does not have a valid async function?

[tinganho]

@rbuckton I think they are correctly defined. There are no compile errors though.

I think I narrowed down the root cause. The one file that is not including an __awaiter on the top has some circular dependencies. At least, when I remove the circular dependency the __awaiter comes back.

[tinganho]

@rbuckton @DanielRosenwasser I could produce a self contained test now:

a.ts:

import { b } from './b';
export let a = {
    f: async () => {
        await b.f();
    }
}

b.ts

import { a } from './a';
export let b = {
    f: async () => {
        await a.f();
    }
}

shell:

tsc a.ts --target es6

output of a.js:

import { b } from './b';
export let a = {
    f: () => __awaiter(this, void 0, Promise, function* () {
        yield b.f();
    })
};

No, __awaiter on a.js.

[DanielRosenwasser]

Confirmed; b.js is getting an awaiter, but not a.js.