The callback that returns a new array of errors that includes the given error, or returns the prevErrors as if there are no changes. By default, only identity-based-unique errors are added.
prevErrors
The error associated with the field.
The array of existing errors.
The new error to add.
The new array of errors that includes the given error.
The callback that returns a new array of errors that includes the given error, or returns the
prevErrors
as if there are no changes. By default, only identity-based-unique errors are added.