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nyc 15 gives no coverage without the useSpawnWrap option

See original GitHub issue

Link to bug demonstration repository

https://github.com/adjerbetian/nyc-bug-demo-use-spawn

Expected Behavior

I would want to have the coverage, but I get nothing in the output

I tried to debug, and when I use the flag --use-spawn-wrap I get the expected result:

📝 This problem does not occur on nyc@14.

Observed Behavior

Troubleshooting steps

run npx nyc mocha --> ❌ no coverage
run npx nyc --use-spawn-wrap mocha --> ✔️ coverage
still occurring when I put cache: false in my nyc config

Environment Information

  System:
    OS: Linux 4.15 Ubuntu 18.04.4 LTS (Bionic Beaver)
    CPU: (12) x64 Intel(R) Core(TM) i9-8950HK CPU @ 2.90GHz
    Memory: 10.25 GB / 31.07 GB
  Binaries:
    Node: 12.16.1 - /usr/bin/node
    npm: 6.14.4 - /usr/bin/npm
  npmPackages:
    nyc: ^15.0.1 => 15.0.1

Issue Analytics

State:
Created 3 years ago
Comments:5 (3 by maintainers)

Top GitHub Comments

1reaction

coreyfarrellcommented, Apr 15, 2020

Thanks for the update. This is odd as I’m not seeing the issue using 12.16.1 on Fedora either. Without being able to reproduce I think we can close this issue, if you do ever see it again please be sure to post a new issue!

0reactions

coreyfarrellcommented, Apr 21, 2020

Worker threads are not supported by spawn-wrap at all. node-preload is the replacement, if it is failing in a case where spawn-wrap worked I need to see a reproducible demo suit can be fixed. Be aware spawn-wrap fails in many situations, especially on Windows.