Working in SFDX with a scratch org.
I'm setting up a future method to send an email if it fails, trying to get the formatting right, and testing. Now, I've hit a wall:
SINGLE_EMAIL_LIMIT_EXCEEDED, Email limit exceeded: 
Can we do anything to avoid hitting that limit with a scratch org?
UPDATE: what I ended up doing was putting the email bit in a try/catch, with the catch generating a System.debug. That doesn't really help with the formatting, based on how the email I receive actually looks, but it does let me keep testing. Plus, it's probably a smart bit of exception handling that I needed anyway.