@eb110 I actually agree with you. It should be explained (or at least displayed in sample tests) that:

• The input must be trimmed
• The character range is 0-9 for digits between 0-9, and A-J for digits between 10-19
• The function is case insensitive
• If the beginning of the string is convertable, you convert that and ignore whatever is left

Explaining why 'K' is invalid and '4jzaaa' is valid??

What would be a better wording, if you would propose one? ^^

If a character is not within the valid range to generate its base-20 representation, then it is considered invalid, so should return -1

For a 7-kyu kata, simple 'If it cannot be done, return -1.' is too ambigous to be treated as valid description. 81% of rating score confirms that.

!

added and updated to Node 12 as well

Added

No random tests

• Example tests is wrong
• So you allows numbers to be passed in as the argument, but it's not mentioned
• Needs random tests
• Base conversion is a duplicate of many katas

Fixed the descriptions

CoffeeScript translation kumited! Plase accept :D

You should tell in the description what can be the input.

It would be better to say in the description that an invalid value must return -1!-)