Add failing test for power-of-2 hashes

[garrettm]

It seems there is an issue with hash codes that are powers of 2 above 2**32--they cause infinite recursion.

Associated issue: #1176

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[kozlitinaelja]

Thank you @garrettm for adding test! It can be merged when the fix will be ready =)

[leebyron]

Unfortunately this is just part of the contract of hashCode() that this test violates. hashCode() is expected to return a uint type, you could fix your test by instead using:

hashCode() {
  return (2 ** 32) | 0
}

[leebyron]

I just added this note to the documentation, and also included a fix to better handle this case!

[garrettm]

Great, thank you @leebyron