t-prio-queue: check result array bounds
Avoid reading past the end of the "result" array, which could otherwise
happen if the prio-queue were to yield more items than were put into it
due to an implementation bug, or if the array has not enough entries due
to a test bug.
Also check at the end whether all "result" entries were consumed, which
would not be the case if the prio-queue forgot some entries or the test
definition contained too many.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>