It would be possible, but I don't have a good ldap server to test on, especially one I can modify config changes. If you'd like to contribute to the repo, adding a test ldap server that can be used for development would enable a lot more features.
If you have a Debian or Ubuntu system available, installing the `slapd` package (OpenLDAP) would be sufficient to get something on localhost or ldapi:///. RH-based systems have openldap* packages.
You don't really have to do much more than that for the purpose of testing this (no creating of accounts, groups, sub-trees, etc).
Perhaps at most go to the stanza/paragraph that defines "olcDbIndex" values, add a new one, and see if a new index file is created in "olcDbDirectory" (often /var/lib/ldap):