[Fix] no-array-index-key: catch toString and String() usage

[RedTn]

Closes #2140

[ljharb]

This looks good, but it seems like any reference to the index should be warned on, not just .toString or String(). Can we have it do that?

[RedTn]

This looks good, but it seems like any reference to the index should be warned on, not just .toString or String(). Can we have it do that?

This seems a bit tricky to write if I'm trying to explicitly hard code cases to look for. Is there an existing util in the codebase to do this, or something in ESLint? Do we take some sort of recursive algo approach in checking all the nodes arguments and callee's?

[ljharb]

I don't have a specific suggestion. I'd say that any identifier inside a jsx attribute that matches the index should be flagged?

[ljharb]

Let's go ahead and land this, and hopefully there will be further improvements in the future.

[codecov-commenter]

Codecov Report

Merging #2813 (492b5f1) into master (1b307d3) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #2813      +/-   ##
==========================================
+ Coverage   97.64%   97.67%   +0.02%     
==========================================
  Files         121      121              
  Lines        8440     8459      +19     
  Branches     3033     3048      +15     
==========================================
+ Hits         8241     8262      +21     
+ Misses        199      197       -2     

Impacted Files	Coverage Δ
lib/rules/no-array-index-key.js	92.68% <100.00%> (+3.25%)	⬆️

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[RedTn]

Sorry forgot about this. If we open another issue I can take a look again once I have some time. But happy to let others take it if they want to