PeoplePicker Does not throw error when invalid user is bound

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Category

[ ] Enhancement

[ X] Bug

[ ] Question

Version

Please specify what version of the library you are using: [ 3.3.0 ]

Expected / Desired Behavior / Question

If an invalid user is bound to people picker, error must be captured or shown in some manner so that users can update the invalid user with active user

Observed Behavior

When used in conjunction with sharepoint, the list/people column may hold inactive user. When such user is bound to attribute defaultSelectedUsers, then picker will load empty, without indicating any error on UI.

Steps to Reproduce

<PeoplePicker
context={context}
defaultSelectedUsers={["OrphanUser"]}
personSelectionLimit={1}
showtooltip={false}
required={true}
disabled={false}
ensureUser={true}
onGetErrorMessage={(items) => {
var item = items[0];
if(item.Email !=null)
return undefined;
else
return 'Invalid Items'
}}
onChange={
(items) => {
//Set State here
}
}
showHiddenInUI={false}
principalTypes={[PrincipalType.User]}
resolveDelay={1000} />

In the above sample code, the getErrorMessage works great, in conjunction with OnChange. But it is not triggered on component mount or initialized. Hence users will not understand why the picker is empty, when form loads.
In scenarios such as ,people leave organisation and data needs to be updated with new user, we need a UI display which says that input bound to the control is invalid, so that new user can be updated..

Submission Guidelines

Currently, people picker control is not resolving the invalid user, by validating user object within. The outcome of that validation needs to be exposed & made available for display. Either new attribute/function needs to be exposed or onGetErrorMessage needs to be run everytime the PeoplePicker mounted + changed.

Thanks!

Start with the PeoplePicker component and its handling of defaultSelectedUsers, onGetErrorMessage, and component initialization. Reproduce the invalid "OrphanUser" case from the issue, then trace why validation runs on change but not mount. Done means an invalid bound user produces a visible or otherwise exposed error when the picker is initialized, while existing change validation remains working.