When a transaction failed and its rollback ALSO failed to undo a canonical
write (retries exhausted), the old path logged, continued, threw
TransactionRollbackError, and set state='rolled_back' — while the record it
could not undo stayed durable on disk. The caller got an error implying the
write was undone; a read-back showed the record. A failed rollback had no
truthful response (the post-commit response lie).
Give a failed rollback a two-branch honest contract, decided by observation:
both commit paths already hold byte-identical before-images, so after a failed
rollback the store compares current canonical state to them and classifies each
touched record as reconciled, an additive orphan (present when it should be
gone), or a restorative loss (gone/wrong when it should have been restored).
- Adopt-forward: a single-op write whose only damage is a durably-present
orphan — the record the caller asked for — is committed forward (its
generation buffered) and returns success with a loud warning that the derived
index may be incomplete for that id until the next rebuild/repairIndex(). No
error, no double-write; the record is durable and get-able immediately.
- Fail loud + quarantine: a multi-op batch, or ANY restorative loss, throws the
new StoreInconsistentError naming every unreconciled record and its
disposition, and puts the brain into write-quarantine (reads keep working,
writes refused via assertWritable) until repairIndex() reconciles the derived
indexes against canonical and lifts it. The counter is not advanced, and
Transaction.rollback now reports state 'inconsistent' instead of the
'rolled_back' lie when any undo failed.
New: StoreInconsistentError + UnreconciledRecord exported from the root;
repairIndex() forces a rebuild and clears the quarantine. Regression
tests/integration/rollback-trapdoor.test.ts injects index-add-throws +
canonical-delete-undo-fails and pins adopt-forward (durable, get-able, not
quarantined), fail-loud (StoreInconsistentError + quarantine + reads work +
repairIndex lifts it), and the error's record naming.
David Snelling
711d2f046a