[Instrument] LINST Standard Date field Always Required, not working with conditional XIN rules

[christinerogers]

The LINST Standard Date field type seems to be required Always.
Unlike other fields that come with a _status field (e.g. textarea), this field can't be made conditional (not required) using XIN rules.
This is a bug, and there is probably an easy fix based on how textarea (or numeric etc) are implemented.

Example: I have a LINST questionnaire that asks:

1. Was there a surgery done? field: surgery_done yes/no/not answered (Dropdown)
2. What was the date of the surgery? surgery_date date plus not answered (StandardDate)

Question 2 should be required Only If Surgery was actually done -- i.e. surgery_done == yes
and a XIN rule is in place (* see below) to express this dependency.

However this field always gives an error (A date is required, or not answered) even when surgery_done == no.

Note: not answered is a valid option for this field (even when the surgery was done) so Standard Date is the most suitable date type.

(*) This Xin rule should, but does not, make the field conditional:
surgery_date{-}Required{-}surgery_done{@}=={@}yes

suggested fix : check against textarea implementation in the instrument class, which allows Xin rules to override this type of constraint

OR ELSE: Document clearly for users of the Instrument Builder / Linst that Standard Date fields can Never be conditional.

[christinerogers]

might be resolved by #7266 - to be verified

[ridz1208]

@christinerogers nice catch. Fixed in PR linked above