Generate code coverage reports using nyc

[LucianBuzzo]

Change-type: patch
Signed-off-by: Lucian lucian.buzzo@gmail.com

Reasons for making this change

Having code coverage reports is useful for detecting uncovered code paths.

Checklist

• I'm updating documentation
  • I've checked the rendering of the Markdown text I've added
• I'm adding or updating code
  • I've added and/or updated tests
  • I've updated docs if needed
  • I've run npm run cs-format on my branch to conform my code to prettier coding style
• I'm adding a new feature
  • I've updated the playground with an example use of the feature

[epicfaace]

Looks good, but I think we should find a way to publish the reports. Could we maybe integrate travis ci and nyc? Or, maybe it's better to use a tool such as code climate instead so it can easily be published?

[edi9999]

How much does this slow down the tests ?

Can you measure time before / after ?

If it slows down significantly, I would suggest to create a special command in package.json for this (npm test-coverage for example)

[epicfaace]

How much does this slow down the tests ?

Can you measure time before / after ?

If it slows down significantly, I would suggest to create a special command in package.json for this (npm test-coverage for example)

Yeah, I think making a special command is the right way to go, as one wouldn't need to create code coverage reports each time one runs the tests, right?

[LucianBuzzo]

@edi9999 @epicfaace I ran some tests locally and saw, on average, a time increase of ~5s. Whilst this is not a huge increase it is proportionally significant when you consider that the average test run without coverage is only 10s. I'll add a separate command for running the coverage report.
Code climate looks interesting, how about we open a new issue about integrating it into this project?

[epicfaace]

Looks good; let's do that.