lz4wasm catches UnhandledPromiseRejectionWarning and exits node process

[khelkun]

Inside a non terminating program (like an expressjs server). Without require('lz4-asm') module the instruction new Promise((resolve, reject) => { throw new Error("my promise thrown error"); }); produces the following output and does not end the nodejs process:

(node:15532) UnhandledPromiseRejectionWarning: Error: my promise thrown error
    at interfaces.start (G:\algorithm-scheduler\svc\interface.js:43:40)
    at new Promise (<anonymous>)
    at Object.<anonymous> (G:\algorithm-scheduler\svc\interface.js:43:1)
    at Module._compile (internal/modules/cjs/loader.js:1123:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1143:10)
    at Module.load (internal/modules/cjs/loader.js:972:32)
    at Function.Module._load (internal/modules/cjs/loader.js:872:14)
    at Module.require (internal/modules/cjs/loader.js:1012:19)
    at require (internal/modules/cjs/helpers.js:72:18)
    at Object.<anonymous> (G:\algorithm-scheduler\svc\entrypoints.js:8:23)
(node:15532) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:15532) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code

But if I require('lz4-asm') in my program, then the same instruction produces the following output and ends the nodejs process:

Error: my promise thrown error
    at G:\VIZUA\gitlab\3dverse\algobelt\algorithm-scheduler\svc\interface.js:43:40
    at new Promise (<anonymous>)
    at Object.<anonymous> (G:\VIZUA\gitlab\3dverse\algobelt\algorithm-scheduler\svc\interface.js:43:1)
    at Module._compile (internal/modules/cjs/loader.js:1123:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1143:10)
    at Module.load (internal/modules/cjs/loader.js:972:32)
    at Function.Module._load (internal/modules/cjs/loader.js:872:14)
    at Module.require (internal/modules/cjs/loader.js:1012:19)
    at require (internal/modules/cjs/helpers.js:72:18)
    at Object.<anonymous> (G:\VIZUA\gitlab\3dverse\algobelt\algorithm-scheduler\svc\entrypoints.js:8:23)
Error: my promise thrown error
    at G:\VIZUA\gitlab\3dverse\algobelt\algorithm-scheduler\svc\interface.js:43:40
    at new Promise (<anonymous>)
    at Object.<anonymous> (G:\VIZUA\gitlab\3dverse\algobelt\algorithm-scheduler\svc\interface.js:43:1)
    at Module._compile (internal/modules/cjs/loader.js:1123:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1143:10)
    at Module.load (internal/modules/cjs/loader.js:972:32)
    at Function.Module._load (internal/modules/cjs/loader.js:872:14)
    at Module.require (internal/modules/cjs/loader.js:1012:19)
    at require (internal/modules/cjs/helpers.js:72:18)
    at Object.<anonymous> (G:\VIZUA\gitlab\3dverse\algobelt\algorithm-scheduler\svc\entrypoints.js:8:23)
G:\VIZUA\gitlab\3dverse\algobelt\algorithm-scheduler\node_modules\lz4-asm\dist\lz4wasm.js:12
if(r)t=q?require("path").dirname(t)+"/":__dirname+"/",u=function(a,b){w||(w=require("fs"));x||(x=require("path"));a=x.normalize(a);return w.readFileSync(a,b?null:"utf8")},v=function(a){a=u(a,!0);a.buffer||(a=new Uint8Array(a));a.buffer||y("Assertion failed: undefin
ed");return a},1<process.argv.length&&process.argv[1].replace(/\\/g,"/"),process.argv.slice(2),process.on("uncaughtException",function(a){if(!(a instanceof z))throw a;}),process.on("unhandledRejection",y),n=function(a){process.exit(a)},

                                                                                                                                                               ^

RuntimeError: abort(Error: my promise thrown error). Build with -s ASSERTIONS=1 for more info.
    at process.y (G:\VIZUA\gitlab\3dverse\algobelt\algorithm-scheduler\node_modules\lz4-asm\dist\lz4wasm.js:16:393)
    at process.emit (events.js:315:20)
    at processPromiseRejections (internal/process/promises.js:209:33)
    at processTicksAndRejections (internal/process/task_queues.js:98:32)
npm ERR! code ELIFECYCLE
npm ERR! errno 7
npm ERR! algorithm-scheduler@0.1.0 start: `node svc/main.js`
npm ERR! Exit status 7
npm ERR!
npm ERR! Failed at the algorithm-scheduler@0.1.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\sebtr\AppData\Roaming\npm-cache\_logs\2020-08-27T15_25_02_512Z-debug.log

I tried to figure out where this comes from and how to disable it but I failed. Could you help me please?

[khelkun]

this could be related:
emscripten-core/emscripten#11768

and the workaround would be:
emscripten-core/emscripten#9061

@STUkh @ukyo
Would it be a problem to add -s NODEJS_CATCH_REJECTION=0 to the RELEASE_ARGS of your gulp/emscripten.js ?

[STUkh]

@khelkun created PR to resolve this issue. Nice catch!

[galrose]

@STUkh Hey is this being worked on?

[STUkh]

@galrose It was resolved but I don't see @ukyo merged it. So you can use code with this PR: #7
I recently tried to re-compile this project with latest emcc and it fail with asm build, but wasm is 100% ok. So you can try it out - it works flawlessly