Jest source maps not working

[schw4rzlicht]

Hey there!

I'm pretty new to TypeScript/jest and I spent hours in figuring out why line numbering in failing tests are wrong so please bear with me.

I'm not sure if I missed something or it's an actual bug and I couldn't find anything close to my problem online. When running install(), line numbering breaks, when commenting it out, everything works fine (but of course stack traces don't work any more). It doesn't matter if install() is run in test code or in imported production code, test line numbering always breaks.

I have set up a demo repo over here.

Thanks for your help!

[LinusU]

Did it work with 0.5.18? 🤔

[schw4rzlicht]

I just tested 0.5.0 and 0.5.18 and they both have the same problem.

[andinoJamesV]

Possibly related and probably not this Libs issue istanbuljs/nyc#1323 as Jest uses Istanbul nyc.

Any suggestions?

Also this error is occurring with nyc that is strange

robot@raspberrypi:~/Sketches/JS/Classes/_/o $ ../node_modules/.bin/nyc  --require=../node_modules/source-map-support/register.js  --source-map=false --cache=false --compact=false  ../node_modules/.bin/_mocha Test/Spork.js
Cannot find module '../node_modules/source-map-support/register.js'
Require stack:
- /home/robot/Sketches/JS/Classes/_/node_modules/nyc/bin/nyc.js

Verified that register.js is where it is expected

My suspicion is mix and match CJS and ES module types are the problem?

Lib is working with just mocha though

[andinoJamesV]

So I kept digging into the project and code coverage is built into V8

[schw4rzlicht]

@Heavy-Gray I'm not sure how I could actually help.

My suspicion is mix and match CJS and ES module types are the problem?

Where does that suspicion come from? Did you have a look at the sample I linked above? Do you mean b/c of

{
  "compilerOptions": {
    "esModuleInterop": true
  }
}

https://github.com/schw4rzlicht/node-sourcemap-jest-demo/blob/master/tsconfig.json

[andinoJamesV]

@schw4rzlicht No for sure you can`t I was bouncing around broken libraries and by chance this lib and thread came up.

Just to verify node-source-map-support is working and the problem you are having is in nyc or Jest

[schw4rzlicht]

Just to verify node-source-map-support is working and the problem you are having is in nyc or Jest

Yes. Debugging and stack traces have the right line numbers outside of Jest tests.

[dmaretskyi]

Related issue: jestjs/jest#10330

[stavalfi]

as a workaround:

if (!process.env.TEST_MODE) {
  require('source-map-support').install()
}

until this issue is fixed.

also, https://github.com/evanw/esbuild has impact as well because of this issue. probably https://github.com/swc-project/swc also.

[silasdavis]

Are you using ts-jest? I am seeing this issue when using ts-jest and I have opened a ticket with minimal repro here: kulshekhar/ts-jest#2372