Promise inside QuickJs cannot work

[Lyoko-Jeremie]

I try to use the libsodium-wrapper in QuickJS follow the document, but it hang when await ready .

after some test, i took the strange thing, the Promise will break the VM then i use the code from document .

the mini code in follow :

import {getQuickJS, QuickJSContext, QuickJSHandle, Scope, shouldInterruptAfterDeadline} from 'quickjs-emscripten';


(async () => {
    const QuickJS = await getQuickJS();

    await Scope.withScopeAsync(async (scope) => {
        const vm = scope.manage(QuickJS.newContext());

        const result = vm.evalCode(
            `
(new Promise((resolve, reject) => {
    setTimeout(args => {
        resolve(undefined);
    }, 1000);
})).then(T=>{});
`
        );

        // run in sync way, it return ok.
        // // output:
        // //    Success: {}
        // //    undefined
        // if (result.error) {
        //     console.log('Execution failed:', vm.dump(result.error));
        //     result.error.dispose();
        // } else {
        //     console.log('Success:', vm.dump(result.value));
        //     result.value.dispose();
        // }
        // return;



        // run in async way, it return into strange ?
        // output:
        //    promiseHandle
        //    resolvedResult
        //    resolvedResultPromise Promise { <pending> }
        //    
        // then the process end.


        console.log('promiseHandle');
        const promiseHandle = (vm.unwrapResult(result));

        console.log('resolvedResult');
        const resolvedResultPromise = vm.resolvePromise(promiseHandle);

        console.log('resolvedResultPromise', resolvedResultPromise);
        const resolvedResult = await resolvedResultPromise;    // <============ end on the `await` op

        console.log('promiseHandle.dispose');    // <============ this code be never run
        promiseHandle.dispose();

        console.log('resolvedHandle');
        const resolvedHandle = (vm.unwrapResult(resolvedResult));

        console.log('resolvedHandle', vm.getString(resolvedHandle));

        console.log('resolvedHandle.dispose');
        resolvedHandle.dispose();
    });
})().then(T => {
    console.log(T);
}).catch(E => {
    console.error(E);
});

anything wrong ?

[justjake]

I don’t see a call to executePendingJobs. I think one is needed.

On Wed, Jun 22, 2022 at 9:29 AM LyokoJeremie ***@***.***> wrote: I try to use the libsodium-wrapper in QuickJS follow the document <https://github.com/justjake/quickjs-emscripten#promises>, but it hang when await ready . after some test, i took the strange thing, the Promise will break the VM then i use the code from document <https://github.com/justjake/quickjs-emscripten#promises> . the mini code in follow : import {getQuickJS, QuickJSContext, QuickJSHandle, Scope, shouldInterruptAfterDeadline} from 'quickjs-emscripten'; (async () => { const QuickJS = await getQuickJS(); await Scope.withScopeAsync(async (scope) => { const vm = scope.manage(QuickJS.newContext()); const result = vm.evalCode( `(new Promise((resolve, reject) => { setTimeout(args => { resolve(undefined); }, 1000);})).then(T=>{});` ); // run in sync way, it return ok. // // output: // // Success: {} // // undefined // if (result.error) { // console.log('Execution failed:', vm.dump(result.error)); // result.error.dispose(); // } else { // console.log('Success:', vm.dump(result.value)); // result.value.dispose(); // } // return; // run in async way, it return into strange ? // output: // promiseHandle // resolvedResult // resolvedResultPromise Promise { <pending> } // // then the process end. console.log('promiseHandle'); const promiseHandle = (vm.unwrapResult(result)); console.log('resolvedResult'); const resolvedResultPromise = vm.resolvePromise(promiseHandle); console.log('resolvedResultPromise', resolvedResultPromise); const resolvedResult = await resolvedResultPromise; // <============ end on the `await` op console.log('promiseHandle.dispose'); // <============ this code be never run promiseHandle.dispose(); console.log('resolvedHandle'); const resolvedHandle = (vm.unwrapResult(resolvedResult)); console.log('resolvedHandle', vm.getString(resolvedHandle)); console.log('resolvedHandle.dispose'); resolvedHandle.dispose(); });})().then(T => { console.log(T);}).catch(E => { console.error(E);}); anything wrong ? — Reply to this email directly, view it on GitHub <#67>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AACIKVZXDIDTR2DDXIW577DVQMINJANCNFSM5ZQHPQ4Q> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

-- Jake Teton-Landis (805) 452-0701 ***@***.***

[Lyoko-Jeremie]

@justjake
i think so , but the promise create in the vm , use in the vm , and resolve in the vm , where can i call the executePendingJobs ?

[Lyoko-Jeremie]

i find a JS_BOOL JS_IsJobPending(JSRuntime *rt); function from quickjs.h

https://github.com/bellard/quickjs/blob/2788d71e823b522b178db3b3660ce93689534e6d/quickjs.h#L874

/* JS Job support */


typedef JSValue JSJobFunc(JSContext *ctx, int argc, JSValueConst *argv);
int JS_EnqueueJob(JSContext *ctx, JSJobFunc *job_func, int argc, JSValueConst *argv);


JS_BOOL JS_IsJobPending(JSRuntime *rt);
int JS_ExecutePendingJob(JSRuntime *rt, JSContext **pctx);

the JS_IsJobPending seems like usefull .

---

and after i look up the document, i find some thing :

https://github.com/justjake/quickjs-emscripten/blob/897fded554b9b1c056c830789f407690ed01a2d9/CHANGELOG.md#breaking-changes

executependingjobs()
haspendingjob()

and from the evalcode() comment :

If evaluation returned a handle containing a promise, use resolvePromise to convert it to a native promise and executePendingJobs to finish evaluating the promise.

so, i add vm.runtime.executePendingJobs() call between the vm.resolvePromise and await like follow, the above code work !

        console.log('resolvedResult');
        const resolvedResultPromise = vm.resolvePromise(promiseHandle);


        // add this
        console.log('vm.runtime.hasPendingJob()', vm.runtime.hasPendingJob());    // <============ return true
        console.log('vm.runtime.executePendingJobs()', vm.unwrapResult(vm.runtime.executePendingJobs()));
        console.log('vm.runtime.hasPendingJob()', vm.runtime.hasPendingJob());    // <============ return false


        console.log('resolvedResultPromise', resolvedResultPromise);    // <============ pending on this
        const resolvedResult = await resolvedResultPromise;

---

seems like the document in Readme.md need some update