feat(rules): add jsx-props-no-spread-multi

[SimonSchick]

Please see notes in code.

I think this rule has value in catching some niche bugs, I personally only saw this ~3-4 times throughout my career.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.75%. Comparing base (a944aa5) to head (57bb4f3).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3724      +/-   ##
==========================================
+ Coverage   94.47%   97.75%   +3.28%     
==========================================
  Files         134      135       +1     
  Lines        9613     9630      +17     
  Branches     3486     3490       +4     
==========================================
+ Hits         9082     9414     +332     
+ Misses        531      216     -315     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[ljharb]

Adding a new rule has a cost, and if you’ve only seen it 3-4 times (i never have), i don’t think it’ll be that useful. (Generally it’s better to discuss a new rule in an issue first so it doesn’t feel like work is wasted in the event it’s not merged)

[SimonSchick]

No hard feelings if it's not merged, I understand it's more of a niche thing, worst case I will port it over to my own plugin :)

[SimonSchick]

@ljharb do you have any suggestions where I could sample this rule against a larger set of JSX code in the wild? Github search hasn't been particularly helpful due to the lack of ast node search.

I ran this rule again some internal code bases and found 2 more violations which is still not statistically significant but an indicator that this may be more wide-spread than I thought.

[SimonSchick]

Any interest/thoughts on this? If not I will close this PR eow and move into a separate library.

[ljharb]

@SimonSchick we use https://www.npmjs.com/package/eslint-remote-tester to test things weekly, that might be worth looking into?

[SimonSchick]

Updated, but CI seems to be wonky, I rebased ontop of upstream (this repo).