Regression: Linux: (edge case) nyc returns 0% coverage if Node.js binary has permissions to bind to ports < 1024 via setcap

To reproduce

1. Install the simple test app.

   git clone https://github.com/aral/simple-demonstration-of-nyc-bug-1281 bug-1281
   cd bug-1281
   npm i
   

2. Ensure Node.js does not have permissions to access privileged ports:

   sudo setcap 'cap_net_bind_service=-ep' `which node`
   

3. npm run coverage succeeds (100%)
4. Get permissions for Node to bind to ports < 1024:

   sudo setcap 'cap_net_bind_service=+ep' `which node`
   

5. npm run coverage fails (0%)

Run the second step again to return to being able to use nyc properly.

It appears that using setcap to set permissions has side-effects. e.g., see this: Linux capabilities (setcap) seems to disable LD_LIBRARY_PATH.

What should happen

Coverage should be 100% at Step 5.

What actually happens

Coverage is 0% at Step 5.

Regression

Works with nyc@14.1.1 (with both Tape 4.11.0 and Tape 5.0.0). The issue occurs on nyc@15.0.1.

<strike>

To reproduce

1. Check out the git repo at https://source.ind.ie/site.js/app (branch: hugo)
2. Run ./install
3. Run npm run coverage

What happens (nyc version 15.0.0)

Incorrectly reports 0% coverage:

> @small-tech/site.js@12.11.0 coverage /home/aral/small-tech/site.js/app
> QUIET=true nyc tape test/*.js | tap-nyc

    ----------|---------|----------|---------|---------|-------------------
    File      | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
    ----------|---------|----------|---------|---------|-------------------
    All files |       0 |        0 |       0 |       0 |                   
    ----------|---------|----------|---------|---------|-------------------

  total:     143
  passing:   143

  duration:  680ms

What happens (nyc version 14.1.1)

Works correctly:

> @small-tech/site.js@12.11.0 coverage /home/aral/small-tech/site.js/app
> QUIET=true nyc tape test/*.js | tap-nyc

    -----------------------|----------|----------|----------|----------|-------------------|
    File                   |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
    -----------------------|----------|----------|----------|----------|-------------------|
    All files              |    36.68 |    24.61 |    36.76 |     37.5 |                   |
     app                   |    56.76 |    39.44 |    63.08 |     58.5 |                   |
      index.js             |    56.76 |    39.44 |    63.08 |     58.5 |... 97,898,899,900 |
     app/bin/commands      |    12.24 |        0 |        0 |    12.24 |                   |
      serve.js             |    12.24 |        0 |        0 |    12.24 |... 50,353,357,359 |
     app/bin/lib           |    15.69 |     12.5 |     5.13 |    15.67 |                   |
      RsyncWatcher.js      |     7.69 |        0 |        0 |     7.95 |... 91,192,193,195 |
      cli.js               |      100 |      100 |      100 |      100 |                   |
      console-timestamp.js |    14.29 |      100 |        0 |    14.29 |    4,5,9,10,11,12 |
      ensure.js            |     8.79 |        0 |        0 |     8.99 |... 97,199,202,203 |
      runtime.js           |      100 |       75 |      100 |      100 |                16 |
      status.js            |    14.29 |        0 |        0 |    14.29 |... 35,36,37,39,42 |
      sync.js              |      9.8 |        0 |        0 |      9.8 |... 15,119,120,126 |
     app/lib               |    53.23 |    44.44 |    38.89 |    57.89 |                   |
      Stats.js             |       50 |       44 |    35.29 |    54.72 |... 18,120,122,124 |
      clr.js               |      100 |       50 |      100 |      100 |                 6 |
      errors.js            |      100 |      100 |      100 |      100 |                   |
    -----------------------|----------|----------|----------|----------|-------------------|

  total:     143
  passing:   143

  duration:  1.7s

Environment Information

  System:
    OS: Linux 5.3 Pop!_OS 19.10
    CPU: (8) x64 Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz
    Memory: 1.15 GB / 15.35 GB
  Binaries:
    Node: 12.14.1 - ~/.nvm/versions/node/v12.14.1/bin/node
    Yarn: 1.21.1 - /usr/bin/yarn
    npm: 6.13.7 - ~/.nvm/versions/node/v12.14.1/bin/npm
  npmPackages:
    nyc: ^14.1.1 => 14.1.1 

</strike>

[ljharb]

In that case it’s unlikely to be a regression in tape itself; please let me know if there’s anything actionable on tape’s side.

[AndyOGo]

@ljharb Thank you very much for your input.

No, I get tape ^4.9.0 through stylelint-test-rule-tape https://github.com/stylelint/stylelint-test-rule-tape/blob/6279a6512269720e737aa06490a6bf8f4d27fa31/package.json#L26