Fixed annual week and day period logic.

Author: amyjko

CHANGELOG

@@ -9,6 +9,7 @@ Dates should be in`YYYY-MM-DD` format and versions are in [semantic versioning](
 
 - Updated minor dependencies.
 - Updated to `write-excel-file` 3.0.
+- Fixed annual week and day period logic.
 
 ## v0.8.7 2026-02-08
 

src/database/Period.test.ts

@@ -13,7 +13,7 @@ test.each([
 	[new Date(2024, 0, 18), { type: 'monthly-weekday', week: 3, day: 3 }, new Date(2024, 1, 21)],
 	[new Date(2024, 0, 1), { type: 'weekly', weeks: 1, day: 7 }, new Date(2024, 0, 7)],
 	[new Date(2024, 0, 8), { type: 'weekly', weeks: 1, day: 7 }, new Date(2024, 0, 14)]
-] as [Date, Period, Date][])(
+] satisfies [Date, Period, Date][])(
 	'%s + %s should be %s',
 	(now: Date, period: Period, expected: Date) => {
 		expect(getNextPeriodDate(now.getTime(), period).getTime() === expected.getTime()).toBe(true);

src/database/Period.ts

@@ -3,7 +3,7 @@ import type { ProcessRow } from './Organization';
 
 /** e.g., Every March 1st. Month 1-12, date 1-31 */
 export type AnnualDate = { type: 'annually-date'; month: number; date: number };
-/** e.g., Every 13th week on Monday. Week 1-52, day 1-7 */
+/** e.g., Every 13th week on Monday. Week 1-52, day 1-7, starting Monday. */
 export type AnnuallyWeek = { type: 'annually-week'; week: number; day: number };
 /** e.g., Every 1st of the month. Day 1-31 */
 export type MonthlyDate = { type: 'monthly-date'; day: number };
@@ -30,8 +30,12 @@ export function getNextPeriodDate(timestamp: number, period: Period): Date {
 			do {
 				const yearWeek = getWeek(nextDate, { weekStartsOn: 1 });
 				const weekDay = getDay(nextDate);
-				// Note that the day of weeks in the library starts at 0 on Sunday, but we number starting on Monday at 1, so no conversion is needed.
-				if (yearWeek === period.week && weekDay === period.day - 1) break;
+				// Note that the day of weeks in the library starts at 0 on Sunday, but we number starting on Monday at 1, so no conversion is needed, aside from Sunday.
+				if (
+					yearWeek === period.week &&
+					((period.day === 7 && weekDay === 0) || weekDay === period.day)
+				)
+					break;
 				else nextDate = addDays(nextDate, 1);
 			} while (nextDate);
 			return nextDate;

test-results/.last-run.json

@@ -1,4 +1,4 @@
 {
-  "status": "passed",
+  "status": "interrupted",
   "failedTests": []
 }