#523 / #525 fix the crash where get_known_periods/get_known_branch_periods split storage keys on every colon, but the underlying key scheme has deeper, pre-existing structural problems (surfaced in cross-family review of #525):
str(period) is lossy for day-anchored periods. Keys embed f"{branch_name}:{period}", and Period.__str__ drops the day for e.g. month:2027-11-15:2 / year:2027-11-15:2, so distinct valid periods can collide in the cache and the readers reconstruct date-shifted periods.- Branch names have no enforced grammar.
Simulation.get_branch accepts arbitrary names; a branch name containing : breaks split(":", 1) parsing in the readers and in delete.
OnDiskStorage has the same defect class with _ as the separator ({branch}_{period} + unconstrained split("_")): a branch name like my_reform mis-parses, and complex-period colons produce awkward filenames.
The clean fix is structured keys — (branch_name, Period) tuples in memory and an escaped/encoded filename scheme on disk — rather than string round-trips. That is a storage-format refactor deserving its own design + review, hence this issue rather than a rider on #525.
#523 / #525 fix the crash where
get_known_periods/get_known_branch_periodssplit storage keys on every colon, but the underlying key scheme has deeper, pre-existing structural problems (surfaced in cross-family review of #525):str(period)is lossy for day-anchored periods. Keys embedf"{branch_name}:{period}", andPeriod.__str__drops the day for e.g.month:2027-11-15:2/year:2027-11-15:2, so distinct valid periods can collide in the cache and the readers reconstruct date-shifted periods.Simulation.get_branchaccepts arbitrary names; a branch name containing:breakssplit(":", 1)parsing in the readers and indelete.OnDiskStoragehas the same defect class with_as the separator ({branch}_{period}+ unconstrainedsplit("_")): a branch name likemy_reformmis-parses, and complex-period colons produce awkward filenames.The clean fix is structured keys —
(branch_name, Period)tuples in memory and an escaped/encoded filename scheme on disk — rather than string round-trips. That is a storage-format refactor deserving its own design + review, hence this issue rather than a rider on #525.