Unit Test Frontend

[fcollonval]

My bad on this one - there is no front-end tests anymore

This should be corrected - especially the cells rechunk + chunk/comment matching need desperately tests.

[bollwyvl]

Ha, in starting #30, I didn't realize that all of the tests were broken! I'll be just turning them off!

I think before we even do this, we should:

• turn on as many compiler options as possible
  • strictNullCheck alone can save many headaches
• increase the aggression of the linter
  • pulling more of the current baseline configuration from core is probably the quickest way

Once we do bring back pure jest unit tests (which invoke no browser), I propose we:

• leverage our JSON Schema from Add OpenAPI description of the extension API #17
  • ideally with something like fast-check and json-schema-fast-check
  • this is massively useful at finding corner cases, as getting JSON validation into different parts of the app will cut down on ambiguous data
• move as many operations against data as we can out of react components and their event handlers/didShouldCouldMaybeUnMounts (Move to VDomRendererModel #19) into discrete, testable functions of manager/model classes which don't require reasoning about the react lifecycle
• get them under coverage, with a threshold, uploaded to codecov
• only run them linux
  • since they only run in nodejs, we're testing... nodejs. no users will be running server-side node.
  • this can gate heavier browser-based tests

[bollwyvl]

Closed by #33