import assert from "node:assert/strict";
import test from "node:test";
import { householdDateAt } from "../../src/lib/household-timezone";

test("householdDateAt preserves 9 AM across Chicago daylight saving time", () => {
  const formatter = new Intl.DateTimeFormat("en-CA", {
    timeZone: "America/Chicago",
    hour: "2-digit",
    minute: "2-digit",
    hourCycle: "h23",
  });

  for (const date of ["2026-01-15", "2026-07-15"]) {
    assert.equal(formatter.format(householdDateAt(date, 9, "America/Chicago")), "09:00");
  }
});