Time validation messages are misleading when editing a parent mount

Summary

When I have a child mount and edit the parent mount information, the validation messages often seem to be related to the child mount.

Especially wrong is it when I have an unlimited child mount & want to set an end date for the parent mount, showing "unmount date must not be empty" (I'm currently reviewing !385 (merged), the error message might mention end date instead of unmount date, but the overall problem is the same).

Steps to reproduce

1. Create a platform
2. Create a device
3. Create a configuration
4. Mount the platform on the configuration unlimited
5. Mount the device with the platform as parent platform, also unlimited
6. Go into the edit mount form for the platform mount
7. Try to set an end date

What is the current bug behavior?

The frontend shows an error message (which is right) but it doesn't make sense in the context of editing the parent mount. The error message seem to have in mind that the user edits the child mount (where we would then need an end date (aka unmount date) for the child if we take the entered end date for the parent into consideration.

What is the expected correct behavior?

It should show that the field for the unmount of the parent must be empty.

Some logs and/or screenshots

Dates for the platform mount:

Dates for the device mount:

Try to set an unmount date for the platform:

Possible fixes

ToDo's

• Bug reproduced
• Cause found
• Bug fixed