Environment

Knex version: 3.1.0
Database + version: posgtres 14.2
OS: MacOS 13.5.1

Bug

1. Explain what kind of behaviour you are getting and how you think it should do

When a transaction callback rejects with undefined, the transaction promise is resolved.

await knex.transaction(() => Promise.reject());
console.log('No failure.');

I think the expected behavior should be promise rejection, because in JavaScript exceptions (and promise rejection reasons) can be of any type (including undefined).

2. This happens because we pass undefined to transaction.rollback() here:
   

   knex/lib/execution/transaction.js

   Lines 242 to 244 in 9659a20

   	.catch((err) => {
   	return transactor.rollback(err);
   	});

And if doNotRejectOnRollback enabled (it is by default) and the passed error is undefined, we do resolve: