silverbullet-icalendar/conductor/tracks/fix_rrule_until_conversion_20260219/spec.md

Specification: Fix RRULE UNTIL Object Conversion

Overview

The conversion of RRULE objects to strings fails for nested objects like UNTIL dates, resulting in UNTIL=[object Object]. This causes the rrule library to fail during expansion.

Functional Requirements

• Robust Value Formatting: Implement formatRRuleValue to handle various types of RRULE values:
  • Date Objects: Convert to YYYYMMDDTHHMMSSZ.
  • Nested Date Objects: (e.g., { date: Date } from ts-ics) Extract and convert.
  • Other Types: Default to string conversion.
• Mapping Preservation: Maintain the existing RRULE_KEY_MAP for key translation.

Implementation Steps

1. Reproduce: Add test expandRecurrences - object rrule with until in icalendar_test.ts using a Date object for until. Verify it fails with Invalid UNTIL value.
2. Fix: Update expandRecurrences in icalendar.ts to use a formatting helper for values.
3. Verify: Confirm the test case passes.

Acceptance Criteria

• Test expandRecurrences - object rrule with until passes.
• The generated string correctly represents the date (e.g., UNTIL=20260219T000000Z).