Support for --trace-warnings option?

[bitliner]

I would need to run ts-node and print stack trace for unhandled promise exceptions.

How to pass an option --trace-warnings?

[blakeembrey]

Feel free to submit a PR. It would need to be added to

ts-node/src/bin.ts

Line 19 in c57ded2

const knownFlags = v8flags.concat([

. This code may be refactored before 4.0 though because of #459 and would also result in resolving this.

[stelcheck]

@bitliner made a PR to add the flag, see #476

[blakeembrey]

@stelcheck If you can split out this issue with the other one, I can merge one before the other. Thanks!

[stelcheck]

Done.

[kateile]

@stelcheck how to use it?
I tried adding script in package.json as
"dev": "ts-node --trace-warnings src/server.tsx",
but i get error when run it

[stelcheck]

Have a look at https://medium.com/the-node-js-collection/node-options-has-landed-in-8-x-5fba57af703d - this should allow you to define Node.JS flags and options through environment variables.

[Elyx0]

Doesn't work @stelcheck still getting the error on --trace-warnings

[Elyx0]

node  --trace-warnings -r ts-node/register -r tsconfig-paths/register ./src/index.ts

For future reference, this worked

[LeonardoRick]

should I be able to run ts-node --trace-warnings in 2020?

[cspotcode]

In 2020 specifically, you're supposed to do this: #465 (comment)

If you find yourself in 2019, you might need to do something else.

[Psychosynthesis]

In 2020 specifically, you're supposed to do this: #465 (comment)

If you find yourself in 2019, you might need to do something else.

It work, but looks awful. Why can't just add a parameter to the ts-node section in the config?

[cspotcode]

@Psychosynthesis This has been discussed many times before, but the short of it is: not possible because we don't spawn a subprocess. Doing so adds extra complexity for users and maintainers, and incurs a performance penalty.

[LeanKhan]

ts-node-dev --trace-warnings --respawn --transpileOnly ./src/server.ts

I use this and it works 🤔

[benallfree]

ts-node-dev --trace-warnings --respawn --transpileOnly ./src/server.ts

I use this and it works 🤔

@LeanKhan Doesn't work. When I run it, I get:

ts-node-dev: no script to run provided
Usage: ts-node-dev [options] script [arguments]

[LeanKhan]

@benallfree I was using a previous version of ts-node:
^1.0.0-pre.39. It stopped working when I updated to ^1.1.8 Now I have to find another way or rollback to that version...

[aymantaybi]

for anyone who wants to run ts-node and print stack trace for unhandled promise exceptions.

node --loader ts-node/esm --trace-warnings exemple/index.ts

make sure to have ts-node installed as a dev dependency.

[amanjha8100]

I still get error with this --trace-warnings flag. Has no one fixed it yet.