fix: preserve calendar date for whole-day events with non-UTC offsets - #91
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fix: preserve calendar date for whole-day events with non-UTC offsets#91dominik1001 wants to merge 2 commits into
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new Date(iso) preserves the input's UTC instant, not its local calendar
date. ts-caldav then derives the stored VALUE=DATE via
date.toISOString().split("T")[0], which truncates any offset east of
UTC back by one day. Anchor whole-day start/end/until at UTC midnight
of the input's calendar date instead, so the truncation is a no-op.
Fixes #89
Unit tests mock the CalDAV client, so they stop short of the boundary where the #89 bug actually lived: ts-caldav's serialization and a real server's storage/parsing of VALUE=DATE. Extend scripts/smoke.ts with a create -> list -> delete round trip using a non-UTC-offset (+09:00) whole-day event, asserting the listed date matches the input calendar date rather than shifting a day earlier.
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Summary
Whole-day events created (or updated) with a local-midnight ISO datetime at a positive UTC offset (e.g.
2026-09-30T00:00:00+09:00) were stored one calendar day early on the server.Root cause
new Date(iso)preserves the input's UTC instant, not its local calendar date.ts-caldavthen derives the storedVALUE=DATE(forDTSTART/DTEND/RRULE UNTILon whole-day events) viadate.toISOString().split("T")[0]. For any offset east of UTC, that truncation silently rolls the calendar date back by one day — e.g.2026-09-30T00:00:00+09:00becomes the UTC instant2026-09-29T15:00:00.000Z, which truncates to2026-09-29.Fix
Added
toWholeDayDate()(src/tools/whole-day-date.ts), which takes the calendar date directly from the ISO input string and anchors it at UTC midnight, sots-caldav's latertoISOString()truncation is a no-op.create-eventandupdate-eventnow use it forstart/end/recurrenceRule.untilwhenever the event is (or is being updated to be, or already is) whole-day.update-eventfalls back to the existing event'swholeDayflag when the caller doesn't pass one explicitly, so partial updates (e.g. just changingstart) on an existing whole-day event stay date-correct too.Test plan
npm run validate(check + test + knip + docs:check + build) passes locallywhole-day-date.test.tscover UTC,+09:00,-07:00, month-end (Jan 31, Sep 30), and leap day (Feb 29) inputscreate-event.test.ts/update-event.test.tsreproduce the exact scenario from the issue (Asia/Seoul+09:00, includingrecurrenceRule.until) and assert the stored date is unchangedscripts/smoke.ts(create → list → delete with a+09:00input) so the fix is also verified end-to-end against a real CalDAV server, since the unit tests mock the client and don't exercisets-caldav's actual serialization or a real server's storage/parsing. Not run here (no live CalDAV server in this environment) — needsnpm run smokeagainst a real server to confirm.Fixes #89