[DatePicker] DateTableComponent generates incorrect calendar grid with custom DateAdapter in v22

[saeidi-dev]

Reproduction link

https://stackblitz.com/edit/ng-zorro-antd

Description

When using a custom NzDateAdapter implementation for a non-Gregorian calendar (such as Jalali calendar), the month table generated by DateTableComponent is not correctly calculated based on the provided adapter.

The calendar view appears to mix native Date (Gregorian) calculations with the custom calendar implementation. As a result, the generated days grid (including previous/next month days and the current month days) does not match the expected Jalali calendar structure.

After debugging DateTableComponent, I noticed that the month grid generation is mainly performed through CandyDate operations:

• calendarStart()
• addDays()
• isToday()
• isSameDay()
• isSameMonth()

Since these operations are responsible for generating the calendar cells and determining the "Today" state, I suspect that some calendar calculations may not fully respect the configured NzDateAdapter.

With a custom Jalali DateAdapter, the displayed month grid and the highlighted "Today" cell do not match the expected Jalali calendar behavior.

Could you please confirm whether CandyDate is expected to be adapter-aware for custom calendar implementations?

Steps to reproduce

1. Create an Angular application with NG-ZORRO v22.
2. Provide a custom NzDateAdapter for Jalali calendar support.
3. Render an nz-date-picker.
4. Open the date picker panel.
5. Navigate between months and inspect the generated day table.
6. Compare the displayed grid with the expected Jalali calendar.

What is expected?

DateTableComponent should build the month grid entirely using the configured NzDateAdapter.

All calculations related to:

• first day of month
• number of days in month
• previous/next month overflow days
• day of week calculation

should respect the custom calendar implementation.

What is actually happening?

The generated date table does not match the custom calendar.

The month grid seems to be calculated using native Gregorian Date behavior in some parts instead of delegating all calendar calculations to NzDateAdapter.

This causes incorrect day positions and incorrect "Today" highlighting when using a Jalali DateAdapter.

DateTableComponent --->CandyDate ---> native Date

---

DateTableComponent ---> NzDateAdapter ---> Jalali calendar

Environment	Info
ng-zorro-antd	22.0.0
Browser	chrome

@Laffery

[Laffery]

Thank you for the report. Migrating away from CandyDate is a substantial breaking change. We plan to make incremental progress in upcoming minor releases and remove CandyDate completely in v23.

[saeidi-dev]

Thank you for the clarification.

It is great to know that the removal of CandyDate is already planned for v23. Thank you for the clarification.

Since this issue affects all custom NzDateAdapter implementations for non-Gregorian calendars (such as Jalali), I would appreciate it if this could be considered as part of the roadmap for the migration.

@Laffery

[aminhavasi]

Hi @Laffery and team,

We are facing the exact same issue in our production enterprise application after updating to NG-ZORRO v22. Non-Gregorian (Jalali) calendar support via custom NzDateAdapter is completely broken due to internal CandyDate assumptions in DateTableComponent.

Since waiting for v23 puts our project on hold, is there any chance for an incremental fix or an opt-in workaround/hook in the upcoming minor release (v22.x) to allow DateTableComponent to delegate grid calculations directly to NzDateAdapter?

Highly appreciate your hard work and looking forward to any interim solutions. Thanks!