Support top-level-await

[swwind]

$ node -v
v14.13.1

$ cat index.js 
console.log(await Promise.resolve(233));

$ cat package.json 
{
  "type": "module"
}

$ node index.js
233

$ pkg index.js -t node14
> pkg@4.4.9
> Error! Unexpected token, expected "," (1:18)
  /home/swwind/Repositories/tmp/index.js

[Dunky13]

I have the same issue, top level await doesn't want to compile.

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[github-actions]

This issue is now closed due to inactivity, you can of course reopen or reference this issue if you see fit.

[Dunky13]

Still an issue

[robertsLando]

Does the issue persists on 4.5.1?

[Dunky13]

Yes,

4.5.1: > Error! 'await' is only allowed within async functions (45:12)

tsconfig.json
target: ESNext
module: ESNext
moduleResolution: node

package.json
type: module
"pkg": {
        "options": [
            "loader=ts-node/esm.mjs",
            "experimental-top-level-await",
            "harmony-top-level-await"
        ]
    },

[robertsLando]

That's strange, @jesec any clue?

[Dunky13]

I will share a MVP example soon here

[jesec]

Top level await is not allowed in any of the current Node versions supported by pkg. This is expected behavior.

[robertsLando]

@jesec node 13.3+ should allow that, just needs a flag --harmony-top-level-await

[jesec]

Need --harmony-top-level-await and only allowed in ESM mode.

[robertsLando]

I have edited my comment, btw I think that we already have versions that support it we should understand why it is not working, maybe node options are not correctly applied on start?

[jesec]

This should be treated as a feature request. We can’t support every experimental Node feature out there.

[robertsLando]

I think we should add it here?

pkg/lib/fabricator.ts

Line 56 in 6deb812

const activeBakes = bakes.filter((bake) => {

[Dunky13]

I've shared the (trunkated) settings I've tried to use. But even with harmony-top-level-await

[erossignon]

// a.js
console.log(await Promise.resolve(42));

doesn't work with nodejs either the and this is the expected behavior. top level await is not supported yet in nodejs by default unless you use the --harmony-top-level-await flag)

$ node a.js
console.log(await Promise.resolve(42));
               ^^^^^

SyntaxError: missing ) after argument list

a simple workaround is to wrap the async call into an async function

(async ()=>{
  console.log(await Promise.resolve(42));
})();

[robertsLando]

doesn't work with nodejs either and this is the expected behavior (top level await is not supported yet in nodejs)

Not correct, it is supported starting from nodejs 13.3+ but requires a flag, see my comment #997 (comment)

[Dunky13]

@robertsLando how should I run pkg then, I can't seem to get it to work.

[robertsLando]

I'm not 100% sure but you may need to add that option on fabricator.js @Dunky13, I have linked you the line in my prev comment

[jesec]

Features are hidden behind flags for a reason.

[Dunky13]

That I understand, but as stated in #997 (comment) I tried enabling these flags in package.json

[Digicrat]

A flag is not required when using await on an import statement, ie: "await import('node-fetch')".

This bug is preventing me from building an application that uses the above syntax to conditionally import a library in code meant to run in either browser or node. This is distinct from using await in general, which I didn't even know there was a flag to enable before seeing this thread.

Edit: There appear to be other issues as well causing 'Failed to make bytecode' when using ES6 module imports after temporarily disabling the above syntax.

[markwylde]

I get the same error:

Error! 'await' is only allowed within async functions

When using the node16 target, of which top level await is enabled by default.

[vsnthdev]

I get the same error:

Error! 'await' is only allowed within async functions

When using the node16 target, of which top level await is enabled by default.

Yup, I am also getting the exact same error.

[saostad]

top-level await supported since 2020-08-11 in node js 14.8 without any flag as a default behavior.

[webhype]

This is still an issue and no longer an experimental feature hidden behind a flag.

[ryanblock]

Having this issue as well.

[ksturner]

I'm having this issue as well.

[robertsLando]

@jesec I think this could be fixed once we add support for es modules parsing

[saostad]

@jesec I think this could be fixed once we add support for es modules parsing

is there a road map / ETA for es modules parsing?

[robertsLando]

I created a test here: #1323 and I tried to fix it but I have no idea about the changes needed to make the support of them.

The problem is that actually we are using npm resolve module to get modules paths but it doesn't support es modules yet: browserify/resolve#222

[elijaholmos]

I am also having this issue