test/format fails when all jobs have neither failed nor succeeded and the timer has elapsed. This is because of the following check at the end o the script:

[[ $failure -ne 0 ]] && exit 1
[[ $success -eq 0 ]] && exit 1

When a timer is given to test/format with the -t option, the run stops after the timer has elapsed. The -t does not indicate a maximum time the execution of test/format can last for.

It is possible to have no failures and no successes. We should change test/format not to treat this as a failure.