test: add tests for runner coverage with different stdout column widths

[pmarchini]

While working on #51299, I saw that we don't have snapshot tests related to the test runner's coverage output under different process.stdout.columns.
I think that we should add these tests before working on #51299 in order to have snapshots of the actual behavior before changing it

[nodejs-github-bot]

Review requested:

• @nodejs/test_runner

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.34%. Comparing base (cc26951) to head (3f5526e).
Report is 332 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #54494      +/-   ##
==========================================
- Coverage   87.34%   87.34%   -0.01%     
==========================================
  Files         649      649              
  Lines      182544   182576      +32     
  Branches    35030    35041      +11     
==========================================
+ Hits       159445   159471      +26     
- Misses      16372    16380       +8     
+ Partials     6727     6725       -2     

see 33 files with indirect coverage changes

[cjihrig]

Some of the files are missing newlines at the bottom (GitHub shows a red circle with a line through it). LGTM other than that though. Thanks!

Some of the fixtures also don't follow the style guidelines because we don't lint the fixtures. Let's keep them though since it gives us a wider range of inputs to test coverage on.

By the way, I realize you were testing the formatting of the coverage report here. But, by any chance did you verify the data in the coverage report manually? I'm just asking because I'd like to try getting code coverage stable in the future, so any bugs we can get rid of are one step closer to that.

[pmarchini]

@cjihrig, No, I didn't, but while fixing the styling issues and newlines, I'm also going to take a look at the quality of the coverage itself 😁

[pmarchini]

Hey @cjihrig, I linted the fixture files as much as possible without breaking the tests.
I couldn't import common because the coverage changes depending on the OS, etc.
I've noticed that something similar has been done for other coverage-related fixtures as well.

In the meantime, I added more uncovered lines to create a repro for #51299.

[pmarchini]

@cjihrig this is the same problem reported in the other ticket

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/61379/

[pmarchini]

CI (node-test-linux-ubuntu2204-64) is failing due to a flaky test reported in issue 52550.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/61390/

[nodejs-github-bot]

Landed in bec3425