Move app to apps/web-react in pnpm workspace layout

apps/web-react/app/utils/dates.test.ts

@@ -0,0 +1,86 @@
+import { afterAll, beforeAll, describe, expect, test } from "vitest";
+import {
+	getDateAtNextFullHour,
+	weekNumberToDate,
+	weekNumberToDateRange,
+} from "./dates";
+
+describe("getDateAtNextFullHour", () => {
+	test("returns a date sitting exactly on a full hour (no leftover minutes/seconds/milliseconds)", () => {
+		const result = getDateAtNextFullHour(new Date(2024, 0, 1, 14, 30, 0, 500));
+
+		expect(result).toEqual(new Date(2024, 0, 1, 15, 0, 0, 0));
+	});
+
+	test("advances to the next hour when only seconds/milliseconds are past the hour", () => {
+		const result = getDateAtNextFullHour(new Date(2024, 0, 1, 14, 0, 30, 0));
+
+		expect(result).toEqual(new Date(2024, 0, 1, 15, 0, 0, 0));
+	});
+
+	test("keeps the same hour when already exactly on a full hour", () => {
+		const result = getDateAtNextFullHour(new Date(2024, 0, 1, 14, 0, 0, 0));
+
+		expect(result).toEqual(new Date(2024, 0, 1, 14, 0, 0, 0));
+	});
+});
+
+describe("weekNumberToDate", () => {
+	// Force a timezone west of UTC so the assertion is deterministic regardless
+	// of where the test happens to run (the bug only manifests west of UTC).
+	const originalTimezone = process.env.TZ;
+	beforeAll(() => {
+		process.env.TZ = "America/Los_Angeles";
+	});
+	afterAll(() => {
+		process.env.TZ = originalTimezone;
+	});
+
+	test("returns the Monday of the ISO week regardless of server timezone", () => {
+		// ISO week 1 of 2024 starts on Monday 2024-01-01
+		const start = weekNumberToDate({ week: 1, year: 2024 });
+
+		expect(start.toISOString().slice(0, 10)).toBe("2024-01-01");
+	});
+
+	test("returns the Sunday of the ISO week regardless of server timezone", () => {
+		// ISO week 1 of 2024 ends on Sunday 2024-01-07
+		const end = weekNumberToDate({ week: 1, year: 2024, position: "end" });
+
+		expect(end.toISOString().slice(0, 10)).toBe("2024-01-07");
+	});
+});
+
+describe("weekNumberToDateRange", () => {
+	// Force a timezone west of UTC observing DST so the assertion is deterministic
+	// regardless of where the test happens to run.
+	const originalTimezone = process.env.TZ;
+	beforeAll(() => {
+		process.env.TZ = "America/New_York";
+	});
+	afterAll(() => {
+		process.env.TZ = originalTimezone;
+	});
+
+	const SEVEN_DAYS_MS = 7 * 24 * 60 * 60 * 1000;
+
+	test("spans exactly seven days even when the week contains a DST transition", () => {
+		// US spring-forward 2025 happened on Sunday 2025-03-09, which falls inside
+		// ISO week 10 of 2025 (Mon 2025-03-03 .. Mon 2025-03-10).
+		const { startTime, endTime } = weekNumberToDateRange({
+			week: 10,
+			year: 2025,
+		});
+
+		expect(endTime.getTime() - startTime.getTime()).toBe(SEVEN_DAYS_MS);
+	});
+
+	test("spans exactly seven days for an ordinary week", () => {
+		const { startTime, endTime } = weekNumberToDateRange({
+			week: 20,
+			year: 2025,
+		});
+
+		expect(endTime.getTime() - startTime.getTime()).toBe(SEVEN_DAYS_MS);
+	});
+});