When data dir is not present, we fail as FileNotFound causes org.apache.cassandra.config.DatabaseDescriptor#tryGetSpace to fail

When you download trunk and do ./bin/cassandra -f, this will fail on a fresh clone as “data” directory does not exist.  The failure happens in org.apache.cassandra.config.DatabaseDescriptor#tryGetSpace which throws a new error
 

throw new ConfigurationException("Unable check disk space in '" + dir + "'. Perhaps the Cassandra user does not have the necessary permissions")