deps: move to snafu 0.9 and fjall 3 - #39
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snafu 0.9 makes Location a type alias for std's, which has no public constructor, so eight manual Location::default() sites stop compiling. Location::caller() records the identical site: 0.8's default() was itself track_caller, and these helpers are not, so the chain terminated at the same place either way. fjall 3 swapped its vocabulary -- the whole store is now Database, and what was PartitionHandle is now Keyspace -- and moved persist from the partition handle to the store. The data API is byte-identical either side; only the type names and the open and persist entry points moved. fjall 3 does change the on-disk format, and it fails closed rather than silently: recover() checks the version marker before any journal or manifest recovery runs, so the destructive path that drops segments absent from the manifest never executes against a 2.x store -- it errors and names the migration tool instead. A comment claiming this pin matched kanon's archeion crate is corrected: archeion still pins fjall 2, so the two now diverge.
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Two dependabot bumps that needed real migrations, landed together so the lockfile moves once.
snafu 0.8.9 → 0.9.2.
snafu::Locationis now a type alias for&'static core::panic::Location<'static>, and std'sLocationhas no public constructor. Eight manualLocation::default()sites stop compiling withE0599.Note the existing
snafu-location-migrate.pytool found zero matches here — it targetsLocation::new(file!(), line!(), column!()), a different shape. The fix was applied by hand.Location::caller()records the identical site: 0.8'sdefault()was itself#[track_caller], and these helper functions are not annotated, so the chain terminated at the same place either way. Zero behaviour change — verified by reading both crate sources, not assumed.fjall 2.11.2 → 3.1.9. fjall 3 swapped its vocabulary: the whole store is now
Database, and what wasPartitionHandleis nowKeyspace.persistmoved from the partition handle to the store. The data API (insert/get/remove) is byte-identical either side — only type names and the open/persist entry points moved. All API shapes were read from the vendored 3.1.9 source, not inferred from error text.The on-disk question, answered
fjall 3 does change the on-disk format (
FormatVersion::V3), and it fails closed.Database::recover()callscheck_version()before any journal or segment-manifest recovery runs. Against a 2.x store it logs an error naming the official migration tool (fjall-rs/migrate-v2-v3) and returnsErr(Error::InvalidVersion(...)). The destructive recovery path — the one that deletes segments absent from the levels manifest — is gated behind that check succeeding, so it never runs against a 2.x-written store. Verified atdb.rs:538-554.Practically moot here:
thesauros's fjall-backed persistence dates to 2026-08-16, so a live 2.x keyspace is unlikely to exist. But if one does, it errors loudly rather than eating data.One correction
A WHY comment claimed this pin matched "the same major version kanon's own archeion crate already uses fleet-wide". Checked against kanon
origin/main: archeion still pinsfjall = "2". That claim is now false, so it is replaced with a NOTE flagging the divergence rather than left as stale prose.Decision worth making separately: either archeion takes the same bump, or the two diverge deliberately.
Supersedes #35 and #34.