Enhance tests

[paescuj]

• Enhance the test for the logger option in concurrently as suggested by @gustavohenke in Code Style & Performance Optimizations #334 (comment)
  • While working on this test, I realized that we should extend the corresponding if statement with a check for outputStream, since it doesn't make sense to pass the log to the OutputWriter if there is no output stream.
• Increase coverage on Node.js 12 (we get a score of 💯 with this) by ensuring the logger is always defined in the LogTimings class.
  For this I marked the printExitInfoTimingTable method as private... @gustavohenke Do you think this would be a breaking change?

[coveralls]

Coverage increased (+0.5%) to 100.0% when pulling d7fcb11 on paescuj:enhance-tests into cc05702 on open-cli-tools:main.

[gustavohenke]

Do you think this would be a breaking change?

It's not really documented how it's meant to be used, so probably not?

I never really thought of exposing the flow controllers for their internals, but to allow one to customise which ones they want when manually building their concurrently instance.

[paescuj]

Do you think this would be a breaking change?

It's not really documented how it's meant to be used, so probably not?

I never really thought of exposing the flow controllers for their internals, but to allow one to customise which ones they want when manually building their concurrently instance.

That's how I see it too! Additionally, LogTimings is the only controller with another method besides handle. So IMO it makes sense to mark it private.