Approved

The tests for my .check() function give:

SyntaxError: Unexpected token u in JSON at position 0
    at JSON.parse (<anonymous>)
    at Context.<anonymous> (test.js:47:35)

My code doesn't mention JSON, nor does the problem specification say "keys must not crash when attempting to json serialize them"

...

How exactly do those solutions work? What does codewars interpret a top-level return in a javascript solution as?

check

I think fixed in https://www.codewars.com/kumite/5ee9ba7eb44cc3000fcd6bb1?sel=5eec704497084e002874c861?

The fix is to replace the word CompareOp with Compare in the tests. I tried to fix it, but I'm finding it really hard to work out how to edit a kata translation.

Fixed

https://www.codewars.com/kata/reviews/5ee8e75d95646b0001c7a019/groups/5eea1def259acb0001b959d1

this should be invalidated

ah, i see the issue, typo in an ast node name.

didn't my update above fix that?

knock knock!! you did not completely block operators// see above

just check if theres any "==" operator in solution

Please update Sample Test Cases (change immediate to arith_eq).

Lean translation: https://www.codewars.com/kumite/5eeb6edee8db87001c07b721?sel=5eeb6edee8db87001c07b721

@eric-wieser I'm afraid your current setup is hackable in the way @dramforever mentioned. As for the kata you linked to, I'll admit that I was a bit lax with kata standards when I approved it, back when we were short of Lean content. I'll consider raising an Issue on that kata and fixing it in my spare time.