Hello Jamie,
Can you please tell me, how many lines of code you wrote with or without commenting?

Please, I need to know. Because I'm also trying a universal solution in Go and right now I'm at the crucial point to compare multiple cells to make a decision and I'm over 500 lines (with lots of commenting).

Thank you.

The problem is not the same, your problem is you're using global vars and they keep their values between tests, the sample tests has increasing lenght, that's why they worked (just by luck). You can see the actual value (that your function returns) in those error messages is the same. Make the global vars local and you'll be fine.

I'm having exactly the same problem as you have, but with Go. I've posted a Spoiler comment and waiting for something to happen...