feat: scope option for libraries

[chrisbateman]

Summary

see #299, #208, #178 and updates to docs/CONFIGURATION.md.

I wasn't sure what kind of API you had in mind for this feature, so I won't be offended if you want to go in a different direction!

Test plan

Added some Jest tests, linked locally and tested scope: false/true/"custom" and verified that different class names were generated for each.

[callstack-bot]

Hey @chrisbateman, thank you for your pull request 🤗.
The coverage report for this branch can be viewed here.

[satya164]

Thanks for the PR. Looks good to me. Any harm if we do this by default instead of accepting an option?

My scope idea was to prefix the class name in the generated CSS, like .my-library .cs56ghgd { ... }, so probably shouldn't use scope for the config name, but I also wanted what you did in the PR.

cc @thymikee @zamotany

[chrisbateman]

Gotcha – that'd work for me! I could make that update later today – any suggestions for the config name? prefix? classPrefix?

[chrisbateman]

@satya164 Let me know if this is more like what you were thinking of!

[thymikee]

Just a heads-up: we're working on TS migration in #398 and will let you know once we're done. Would you be so kind and bear with us until it's ready and rebase then?

[pbitkowski]

@satya164 can we merge it after TS migration? Could you take a look?

[chrisbateman]

@thymikee can do - thanks for the update!

[chrisbateman]

@thymikee @satya164 Would there be any value in pointing this PR at the develop branch? Or are y'all planning to merge that to master at some point?

[jayu]

Hi, @chrisbateman Do you have the capacity and will to refactor this to the point it would be possible to merge it to current master?

[amaranth]

How is this different from setting the existing classNameSlug setting to "MyScope_[hash]"?

[jayu]

Lol I didn't notice that :o Looks like classNameSlug PR was introduced after this one was opened. So this PR does not make sense anymore since we have the possibility to add a prefix to the class name. Thanks for that finding @amaranth