format: handle input edge cases (zero decimals)

[sohkai]

Tokens may have 0 decimals (either explicitly declared or just assumed, e.g. for NFTs).

Only added additional test cases that we should handle for now!

[bpierre]

@sohkai Done. For decimal units greater than digits, I was thinking that we could reasonably tolerate it, what do you think?

[sohkai]

Done. For decimal units greater than digits, I was thinking that we could reasonably tolerate it, what do you think?

I'm ok with this too!

I was originally thinking it would be better to be strict, like we are with the negative decimals/digits, but agreed that it's a different case when digits > decimals:

• Negative decimals/digits are just logically wrong
• You may want to specify a digit setting across all of your token displays, e.g. 3-5 (as we do), and not worry about having to do a clamp against provided decimals

[bpierre]

You may want to specify a digit setting across all of your token displays, e.g. 3-5 (as we do), and not worry about having to do a clamp against provided decimals

Good point! 👍