int msgs = Math.min(5, r.nextInt(20));
int unread = Math.max(0, r.nextInt(msgs + 5) - 5);
ParticipantId author = allParticipants.get(r.nextInt(allParticipants.size()));
List<ParticipantId> participants = randomSubsequence(r, allParticipants);
participants.remove(author);
WaveId wid = WaveId.of(domain, "fake" + i);
double lmt = now - r.nextDouble() * week;
digests.add(new DigestSnapshot(title, snippet, wid, author, participants, lmt, unread, msgs));
}
return digests;
}