fix(sync): adopted lexicon frequency no longer double-counts active-session lines

The remote tracker increments imm_words/imm_kanji.frequency live, so a
snapshot holding a stale ACTIVE session (skipped by the merge) has that
session's partial occurrences baked into frequency. A word new to the
local DB adopted that full total, then received the same occurrences
again when the session finalized and merged on a later sync.

Subtract active-session occurrence counts when adopting a new row; they
are re-added exactly once when the session completes. Existing rows were
already safe (isNew guard in addWordOccurrences/addKanjiOccurrences).
Verified red/green: the new two-sync regression test fails without the
subtraction (frequency 9 instead of 5).
This commit is contained in:
2026-07-12 02:18:41 -07:00
parent c9f85473bb
commit f8c10edce0
3 changed files with 110 additions and 5 deletions
@@ -0,0 +1,4 @@
type: fixed
area: sync
- Fixed word/kanji frequencies double-counting across syncs when the remote snapshot contained a stale active session (e.g. after a crash): a word new to the local machine adopted the remote's full lifetime frequency, which already included the active session's partial occurrences, and those occurrences were added again when the session finalized and synced. Newly adopted words/kanji now exclude active-session counts, which arrive once the session completes.