Exdates returning UTC date without TZID offset

[Lawton]

Reporting an issue

I am finding that an rruleset with exclusion dates returns dates without the offset of the timezone within the rruleset.

Example

var r = rrule.rrulestr('DTSTART;TZID=America/New_York:20231114T220000\nRRULE:UNTIL=20231118T220000;INTERVAL=1;FREQ=DAILY\nEXDATE;TZID=America/New_York:20231116T220000');
r.all()
/**
output : [
  2023-11-15T03:00:00.000Z,
  2023-11-16T03:00:00.000Z,
  2023-11-18T03:00:00.000Z,
  2023-11-19T03:00:00.000Z
] ✅ 
*/
r.exdates()
// expected: [ 2023-11-17T03:00:00.000Z ]

// actual: [ 2023-11-16T22:00:00.000Z ]

rrules version: 2.7.2

operating system: macOS 14

timezone: EST

Is this expected behaviour? It seems strange that exdates are not consistent with the instances. Thanks!

---

Thank you for taking an interest in rrule! Please include the following in
your report:

• Verify that you've looked through existing issues for duplicates before
  creating a new one
• Code sample reproducing the issue. Be sure to include all input values you
  are using such as the exact RRule string and dates.
• Expected output
• Actual output
• The version of rrule you are using
• Your operating system
• Your local timezone (run $ date from the command line
  of the machine showing the bug)

[dkelsen]

I noticed this as well.

[sdotson]

Same

[vkartaviy]

+1 having the same issue :(

[SijmenHuizenga]

In an attempt to understand if/how our project is impacted by this report, i wrote below tests. Tests were ran UTC timezone. I see the same situation as described in the issue. Running rrule version 2.8.1.

describe("rrule exdates in timezones", () => {
  it("exdates should return dates in local timezone", () => {
    var r = rruleSdk.rrulestr(
      `DTSTART;TZID=America/New_York:20231114T220000
      RRULE:UNTIL=20231118T220000;INTERVAL=1;FREQ=DAILY
      EXDATE;TZID=America/New_York:20231116T220000`
    ) as rruleSdk.RRuleSet;
    expect(r.all()).toEqual([
      new Date("2023-11-15T03:00:00.000Z"),
      new Date("2023-11-16T03:00:00.000Z"),
      new Date("2023-11-18T03:00:00.000Z"),
      new Date("2023-11-19T03:00:00.000Z"),
    ]);
    expect(r.exdates()).toEqual([new Date("2023-11-17T03:00:00.000Z")]);
  });

  it("re-creating an rruleset should maintain the exdates", () => {
    const rrule = `DTSTART;TZID=America/New_York:20231114T220000
RRULE:UNTIL=20231118T220000;INTERVAL=1;FREQ=DAILY
EXDATE;TZID=America/New_York:20231116T220000`;
    var original = rruleSdk.rrulestr(rrule) as rruleSdk.RRuleSet;

    const copy = new rruleSdk.RRuleSet();
    original.rrules().forEach((r) => copy.rrule(r));
    original.exdates().forEach((exdate) => copy.exdate(exdate));

    expect(rrule).toEqual(copy.toString());
  });
});

  rrule exdates in timezones
    ✕ exdates should return dates in local timezone (10 ms)
    ✓ re-creating an rruleset should maintain the exdates

  ● rrule exdates in timezones › exdates should return dates in local timezone

    expect(received).toEqual(expected) // deep equality

    - Expected  - 1
    + Received  + 1

      Array [
    -   2023-11-17T03:00:00.000Z,
    +   2023-11-16T22:00:00.000Z,
      ]