🛑 Wrong dateUntil when start_date.day == 29 || 30 || 31 & end_date.day == 28 || 29 || 30 || 31

[nitin2953]

Interactive test https://datediff.netlify.app/
Repo https://github.com/nitin2953/date-diff-test

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STARTING WITH 29

Wrong Diff if end_date is 28 Feb (not 29) (Future Only)

DD MMM YYYY	DD MMM YYYY	Temporal	fcTemporal	⭕
Past
29 Jan 2022	28 Feb 2020	-1Y -11M -01D	-1Y -11M -01D	✅
29 Jan 2022	29 Feb 2020	-1Y -11M 00D	-1Y -11M 00D	✅
29 Jan 2022	01 Mar 2020	-1Y -10M -28D	-1Y -10M -28D	✅
29 Jan 2022	27 Feb 2021	0Y -11M -01D	0Y -11M -01D	✅
29 Jan 2022	28 Feb 2021	0Y -11M 00D	0Y -11M 00D	✅
29 Jan 2022	01 Mar 2021	0Y -10M -28D	0Y -10M -28D	✅
Future
29 Jan 2022	27 Feb 2022	0Y 00M 29D	0Y 00M 29D	✅
29 Jan 2022	28 Feb 2022	0Y 01M 00D	0Y 00M 30D	❌
29 Jan 2022	01 Mar 2022	0Y 01M 01D	0Y 01M 01D	✅
29 Jan 2022	27 Feb 2023	1Y 00M 29D	1Y 00M 29D	✅
29 Jan 2022	28 Feb 2023	1Y 01M 00D	1Y 00M 30D	❌
29 Jan 2022	01 Mar 2023	1Y 01M 01D	1Y 01M 01D	✅
29 Jan 2022	28 Feb 2024	2Y 00M 30D	2Y 00M 30D	✅
29 Jan 2022	29 Feb 2024	2Y 01M 00D	2Y 01M 00D	✅
29 Jan 2022	01 Mar 2024	2Y 01M 01D	2Y 01M 01D	✅
29 Jan 2022	27 Feb 2025	3Y 00M 29D	3Y 00M 29D	✅
29 Jan 2022	28 Feb 2025	3Y 01M 00D	3Y 00M 30D	❌
29 Jan 2022	01 Mar 2025	3Y 01M 01D	3Y 01M 01D	✅

STARTING WITH 30

Wrong Diff if end_date is 28/29 Feb (Future Only)

DD MMM YYYY	DD MMM YYYY	Temporal	fcTemporal	⭕
Past
30 Jan 2022	28 Feb 2020	-1Y -11M -01D	-1Y -11M -01D	✅
30 Jan 2022	29 Feb 2020	-1Y -11M 00D	-1Y -11M 00D	✅
30 Jan 2022	01 Mar 2020	-1Y -10M -29D	-1Y -10M -29D	✅
30 Jan 2022	27 Feb 2021	0Y -11M -01D	0Y -11M -01D	✅
30 Jan 2022	28 Feb 2021	0Y -11M 00D	0Y -11M 00D	✅
30 Jan 2022	01 Mar 2021	0Y -10M -29D	0Y -10M -29D	✅
Future
30 Jan 2022	27 Feb 2022	0Y 0M 28D	0Y 0M 28D	✅
30 Jan 2022	28 Feb 2022	0Y 1M 00D	0Y 0M 29D	❌
30 Jan 2022	01 Mar 2022	0Y 1M 01D	0Y 1M 01D	✅
30 Jan 2022	27 Feb 2023	1Y 0M 28D	1Y 0M 28D	✅
30 Jan 2022	28 Feb 2023	1Y 1M 00D	1Y 0M 29D	❌
30 Jan 2022	01 Mar 2023	1Y 1M 01D	1Y 1M 01D	✅
30 Jan 2022	28 Feb 2024	2Y 0M 29D	2Y 0M 29D	✅
30 Jan 2022	29 Feb 2024	2Y 1M 00D	2Y 0M 30D	❌
30 Jan 2022	01 Mar 2024	2Y 1M 01D	2Y 1M 01D	✅
30 Jan 2022	27 Feb 2025	3Y 0M 28D	3Y 0M 28D	✅
30 Jan 2022	28 Feb 2025	3Y 1M 00D	3Y 0M 29D	❌
30 Jan 2022	01 Mar 2025	3Y 1M 01D	3Y 1M 01D	✅

STARTING WITH 31

Wrong Diff if total_days & end_date.day is 30 AND at 28/29 Feb (Future Only)

ℹ	TD = total_days in end_date.month

DD MMM YYYY	DD MMM YYYY	Temporal	fcTemporal	⭕	TD
Past, All ✅
Future
31 Jan 2022	28 Feb 2022	0Y 01M 0D	0Y 0M 28D	❌	28
31 Jan 2022	31 Mar 2022	0Y 02M 0D	0Y 2M 00D	✅	31
31 Jan 2022	30 Apr 2022	0Y 03M 0D	0Y 2M 30D	❌	30
31 Jan 2022	31 May 2022	0Y 04M 0D	0Y 4M 00D	✅	31
31 Jan 2022	30 Jun 2022	0Y 05M 0D	0Y 4M 30D	❌	30
31 Jan 2022	31 Jul 2022	0Y 06M 0D	0Y 6M 00D	✅	31
31 Jan 2022	31 Aug 2022	0Y 07M 0D	0Y 7M 00D	✅	31
31 Jan 2022	30 Sep 2022	0Y 08M 0D	0Y 7M 30D	❌	30
31 Jan 2022	31 Oct 2022	0Y 09M 0D	0Y 9M 00D	✅	31
31 Jan 2022	30 Nov 2022	0Y 10M 0D	0Y 9M 30D	❌	30
31 Jan 2022	31 Dec 2022	0Y 11M 0D	0Y 11M 0D	✅	31
31 Jan 2022	31 Jan 2023	1Y 00M 0D	1Y 0M 00D	✅	31
31 Jan 2022	28 Feb 2023	1Y 01M 0D	1Y 0M 28D	❌	28
	…
31 Jan 2022	29 Feb 2024	2Y 01M 0D	2Y 0M 29D	❌	29

[arshaw]

@nitin2953 , thank you for this incredibly comprehensive bug reports. One of the best bug reports I've seen. I can confirm, this is a bug. I'll fix while I'm refactoring for the next release (more info: https://github.com/fullcalendar/temporal#project-update-2023-04-22)

[digaus]

Any ETA on next release? :)

[arshaw]

Hi @digaus, please see my update here: #3 (comment) (I'm essentially using that thread as a tracking issue for the next release).

[arshaw]

This is fixed in v0.2.0. Please confirm when you have a chance. Thanks!

[nitin2953]

Hi @arshaw,
Thanks for the great work on the refactoring!
The v0.2.0 has fixed all issues but Unfortunately, all those issues have reappeared in v0.2.4
I haven't had the chance to test any versions prior to v0.2.4 and unfortunately, I also don't have the time to update my testing website.

[arshaw]

Hi @nitin2953, I've updated your repro repo here:
https://github.com/fullcalendar/date-diff-test

It's been updated to use the latest "playground" from tc39's reference implementation as well as fullcalendar's temporal-polyfill latest version 0.2.4

I've tried a number of the error cases you originally posted and don't see any difference in behavior between the reference implementation and fullcalendar's polyfill.

The diffing algorithm changed in the tc39 spec a few months ago, and fullcalendar's polyfill adapted to those changes, so maybe you're comparing the new version of one implementation to the old version of the other