The snapshot made the listing stand still; it did not make the handoff safe.
A choice is validated against the snapshot on top when the request lands and
resolved against the snapshot on top when the game thread next looks, and
between those the loop runs evaluations — one that errors pushes a break of
its own, whose loop reaches the flag first and takes its own index 2 for the
one somebody picked off the outer list. That is the failure this change exists
to end, arriving by a different door.
So each snapshot carries a generation, a choice carries the generation it was
validated against, and a loop claims only what is addressed to it. A mismatch
is left set rather than dropped: the listener already answered ok, so the break
it was meant for must still be able to take it. Depth could not do this — an
outer break resuming and a new one starting reuses the number. The snapshot is
also popped before the depth comes down now, so the two never describe
different breaks.
The client's own new path gets tested too: the candidate table is pure, so the
shapes a real daemon will not easily produce are checked directly, and the
break-and-resume test now goes through restart-at rather than by name.
flan-dev-unreachable-restarts was dead on arrival — flan-break reads
:unreachable off its own reply — and is gone.
Joseph Ferano
0c9f043bb1