The --cwd option breaks instrumentation on Windows

Link to bug demonstration repository

https://github.com/elliot-nelson/nyc-bug-demo

Expected Behavior

Running nyc --cwd spec jasmine should instrument the specs run, and produce a coverage report:

1 spec, 0 failures
Finished in 0.023 seconds
Randomized with seed 40333 (jasmine --random=true --seed=40333)
---------------|---------|----------|---------|---------|-------------------
File           | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
---------------|---------|----------|---------|---------|-------------------
All files      |     100 |      100 |     100 |     100 |                   
 index-spec.js |     100 |      100 |     100 |     100 |                   
---------------|---------|----------|---------|---------|-------------------

Observed Behavior

Adding the --cwd option removes all instrumentation:

1 spec, 0 failures
Finished in 0.017 seconds
Randomized with seed 50629 (jasmine --random=true --seed=50629)
----------|---------|----------|---------|---------|-------------------
File      | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s
----------|---------|----------|---------|---------|-------------------
All files |       0 |        0 |       0 |       0 |
----------|---------|----------|---------|---------|-------------------

Troubleshooting steps

• Issue occurs only on Windows (the --cwd flag works as expected on MacOS/Linux)
• Issue does not occur in Windows using nyc@14.1.1 (–cwd flag works as expected)
• Suspecting the issue is with jasmine, I tried modifying the the "spec_dir" setting in spec/support/jasmine.json - this didn’t work (jasmine is running the right files, those files just aren’t instrumented).

Environment Information

npx: installed 1 in 1.869s

  System:
    OS: Windows Server 2012 6.3.9600
    CPU: (2) x64 Intel(R) Xeon(R) CPU E5-2686 v4 @ 2.30GHz
    Memory: 5.63 GB / 8.00 GB
  Binaries:
    Node: 8.15.0 - c:\nodejs\node.EXE
    npm: 6.4.1 - c:\nodejs\npm.CMD
  npmPackages:
    nyc: ^15.0.1 => 15.0.1

[ryancabanas]

I’m new to programming, so I know my statements could be completely off, but I am experiencing an issue using the cwd option too, like @elliot-nelson.

I was using nyc@15.1.0 in my NodeJS project and I had placed the nyc package in a location other than my project’s root folder. When I attempted to use the cwd option to specify the project’s root folder, I got the same empty coverage report like @elliot-nelson showed. I only got valid results if I actually moved the nyc package to my project’s root folder.

If I downgraded to nyc@14.1.1, as @elliot-nelson mentioned, I began getting a valid coverage report even with the nyc package in a folder other than the project’s root folder and using the cwd option to specify the project’s root folder.

I’m not sure if this is helpful at all to this particular thread, but I thought I would mention it, as the content here did help me to find out that I wasn’t going crazy after and I was actually using the cwd option correctly after all. 😃 Thanks!

[addaleax]

@elliot-nelson I think it’s also about the comment I just left on the fix about using path.resolve() instead of path.join() 😃