Kata

In C# version:

Test Failed
  Thats not a valid time!
  Expected: <System.Exception>
  But was:  <System.ArgumentException: Invalid time>

If tests expect instance of exactly System.Exception to be thrown (and that's bad, BTW), it should be mentioned in the description.

Using hours, minutes, and seconds to correspond to R, G, and B -- as I assume you intended -- it would be cool to see how this clock's colours change over the course of the day. It would be easy to code, too! I suppose they'd be rather dark colours, given the constraints for valid h/m/s values. But dark colours are good for a clock background. Maybe I'll go try that...

Perhaps add a hint, that the time is allowed as 00:00:00 - 23:59:59.

C# translation kumited.

Please add these two test cases

Test.expectError('Thats not a valid time!', function() {hexToTime('#0d373c')}); // '13:55:60'
Test.expectError('Thats not a valid time!', function() {hexToTime('#0d3c37')}); // '13:60:55'

It is validating the hour correctly up to 23 (maybe it was a random one, maybe it is best to create one for it too), but tests are not checking the range for minutes and seconds up to 59.

Nice kata. Wrapped up some programming fundamentals in a well-explained and interesting puzzle.

Confusing test cases. The real ones expect an exception while the provided ones only works when I return the error message instead of throwing it. Or was that a part of the Kata? Repairing the provided unit tests?