[Unified search] Consider not clearing the value on the filter builder when the operator changes

[stratoula]

Describe the feature:

Right now on the filter builder every time I change the operator, the value is also cleared. Although I do understand the value in this, I think that changing the many times the user might just want to select the reverted operator (if they have is, they want the is not). At this case is annoying to select the value again. Especially it is frustrating when:

• you have a big list of fields
• you have an array of values (is one of operator) and you have to reselect them

I propose to not clear the values if the operator changes, if the user wants to clear them it is something easily done (comparing to have to select the same values again)

[elasticmachine]

Pinging @elastic/kibana-visualizations @elastic/kibana-visualizations-external (Team:Visualizations)

[stratoula]

cc @MichaelMarcialis @andreadelrio how do you feel about it?

[stratoula]

Clarification:

They should only preserve if they are compatible, for example is -> is not, but not is between -> is
Consider for multivalues to one value to keep only the first option.

[MichaelMarcialis]

cc @MichaelMarcialis @andreadelrio how do you feel about it?

Makes sense to me to keep the value if its compatible with the operator. Am I correct in assuming that changing a field will still reset the operator and value?

[stratoula]

Am I correct in assuming that changing a field will still reset the operator and value?

Correct!

[andreadelrio]

+1 for me on this change. I seem to remember users found this annoying in the small usability testing we conducted in Dec 2022.

[mbondyra]

Here's the table with how we're going to transform/clear/preserve values: