diff database to databaseChangeLog

Liquibase has a tool to create a diff between two databases. But I would like to do a diff between a database and a databaseChangeLog file. The only solution I have is to create an empty database. Then update this temporary database with the change log. And at last do the diff between the temporary database and the target database.

Is there a way to do this directly without need of the temporary DB?

There isn’t a way to do that at this point.  The trouble is that as you get into and custom tags, there is no way to know what is actually happening to the database.