pub(crate) fn check_exit(subject: &ContentHash, body: &str) -> !Expand description
Prints the checks on subject and exits with the trichotomy.
The only command here that has a third answer, and it is the reason
the third answer exists: a caller asking “may I land this” gets three
materially different instructions back, and two exit codes cannot
carry three instructions. 0 land it, 1 do not, 3 not yet.
Nothing reported exits 1, not 3. 3 means a check said it
was running, which is a promise that an outcome is coming. No check
at all is not that promise – there may be no runner configured, and
a caller that waited would wait forever. Both 1 cases print a
distinguishing verdict, so a human is never left guessing which of
the two they hit.