Issue using YEARLY frequency and BYMONTHDAY

[vkartaviy]

I encountered an error with the recurrence rule that has yearly frequency and a specific month day.

The expected dates are not being generated correctly.

Could you please confirm that issue is exists?

Failed test-case:

#[test]
fn yearly_bymonthday() {
    let rrule_set = "DTSTART;TZID=Asia/Kolkata:20210420T080000\nRRULE:FREQ=YEARLY;BYMONTHDAY=20"
        .parse::<RRuleSet>()
        .unwrap();

    let dates = rrule_set
        .all(5)
        .dates;

    common::check_occurrences(&dates, &[
        "2021-04-20T08:00:00+05:30",
        "2022-04-20T08:00:00+05:30",
        "2023-04-20T08:00:00+05:30",
        "2024-04-20T08:00:00+05:30",
        "2025-04-20T08:00:00+05:30",
    ]);
}

Given: [
    "2021-04-20T08:00:00+05:30",
    "2021-05-20T08:00:00+05:30",
    "2021-06-20T08:00:00+05:30",
    "2021-07-20T08:00:00+05:30",
    "2021-08-20T08:00:00+05:30",
]
Expected: [
    "2021-04-20T08:00:00+05:30",
    "2022-04-20T08:00:00+05:30",
    "2023-04-20T08:00:00+05:30",
    "2024-04-20T08:00:00+05:30",
    "2025-04-20T08:00:00+05:30",
]

[AlbanWS]

Hi,

Your current string says : "Every year on the 20th", which is valid every months.
You want to say : "Every year in May on the 20th".

If you want May (the 4th month) : BYMONTH=4

Therefore your RruleSet string should be :
DTSTART;TZID=Asia/Kolkata:20210420T080000\nRRULE:FREQ=YEARLY;BYMONTH=4;BYMONTHDAY=20

You can try your Rrules here if you want to understand it better

[vkartaviy]

@AlbanWS thanks for the reply, I wish Google Calendar treat it the same, lol 😭