Fix cron expression display for Day-of-Month and Day-of-Week conflicts

[shreyaskj-0710]

Fixes #54482

Description
📌 Day-of-Month (DOM) and Day-of-Week (DOW) Conflict in Cron

In cron syntax, both Day-of-Month (DOM) and Day-of-Week (DOW) fields are evaluated independently.
If both are specified, the schedule runs when either condition matches (logical OR), not when both are true together.

Example

Cron expression : * * */1 * 5

*/1 → effectively means every day of the month

5 → every Friday

Together → Every minute (or) Every minute, only on Friday (but since */1 means every day, the Friday part becomes
redundant).

⚠️ This often causes confusion because users may expect it to mean “every Friday only” when in reality it matches “every day”.

Approach

• Detect when both DOM (Day of the month) and DOW (Day of the week) are restricted (i.e., not "*").
• Then split the expression into two variants:
• One ignoring DOW (DOM only)
• One ignoring DOM (DOW only)

Each variant is described independently, and the final description combines them using “(or)”, which matches actual cron semantics.

In UI Timetable description will be as follows

[shreyaskj-0710]

Hi @uranusjr ,

can you please review the code changes.

[shreyaskj-0710]

Hi @pierrejeambrun , @kaxil

can you please review the changes

[pierrejeambrun]

At first I'm not in favor of this change. I don't really understand why this is needed. I would keep the standard cron description, if users cannot read cron expressions, they should go check the documentation. (I'm not strongly against it if this helps users)

Can you add relevant tests please.

[shreyaskj-0710]

At first I'm not in favor of this change. I don't really understand why this is needed. I would keep the standard cron description, if users cannot read cron expressions, they should go check the documentation. (I'm not strongly against it if this helps users)

Can you add relevant tests please.

Hi @pierrejeambrun ,
Have added the tests

[pierrejeambrun]

@bbovenzi @uranusjr I would love your opinion on that

[bbovenzi]

I mean if this is a more accurate description then sure. I also see the cron-descriptor has the same bug. Looks like we need to rebase and fix some tests though.

[RNHTTR]

I mean if this is a more accurate description then sure. I also see the cron-descriptor has the same bug. Looks like we need to rebase and fix some tests though.

The existing description is objectively incorrect. It's not just more accurate; the existing implementation is broken and the proposed fix makes it not broken.

[pierrejeambrun]

OK I get it now. Current default description is wrong when both are specified. (I tested on other tools and they all do the same mistake).

Yes the tooltip needs to be fixed

Is that the only known 'bug' in the cron description?

• If that's the only one issue with cron description, we can just handle the edge case as suggested in this PR.
• If there are other instances of such common problem with cron description, maybe we shouldn't use the description at all, and let the user read the cron expression instead.

[RNHTTR]

Is that the only known 'bug' in the cron description?

This is the only bug that I'm aware of. Other descriptions appear accurate.

[pierrejeambrun]

This is the only bug that I'm aware of. Other descriptions appear accurate.

Glad to hear. I think we can move forward then.

@shreyaskj-0710 Do you mind rebasing the PR and fixing the CI please.

[shreyaskj-0710]

This is the only bug that I'm aware of. Other descriptions appear accurate.

Glad to hear. I think we can move forward then.

@shreyaskj-0710 Do you mind rebasing the PR and fixing the CI please.

Hi @pierrejeambrun ,

Have updated the PR and fixed the CI

[github-actions]

Backport successfully created: v3-1-test

Status	Branch	Result
✅	v3-1-test