Comment # 25 on bug 984778 from Tony Mechelynck

Upgraded yesterday to the current beta or RC of Leap 15.1.

zypper version is 1.14.27 and its manpage mentions the needs-rebooting command.

It says:
No core libraries or services have been updated.
Reboot is probably not necessary.

and ends with status zero (indeed, ATM my system doesn't need rebooting).

Note that it said the same thing at the end of "zypper --releasever=15.1 dup"
even though the kernel had been updated as part of the distribution upgrade.