I upgraded from a previous beta to RC3 and numerous triggers immediately started failing.

Steps to reproduce:

1. External check such as DNSMatchIP[\{HOST.DNS},\{HOST.IP},\{$OPTIONAL_DOMAINS}]
2. In the host, leave either the host name or the host IP blank (not specified) in the agent interface definition (in my case only agent is defined not snmp, etc.)
3. the script code invoked looks like

   hostname="$1"
   ip="$2"
   addedDomain="$3"
   
   if [ -z $ip ]
   then
       # Consider a blank IP as on purpose, as it implies a DNS lookup for IP anyway
       echo "Ok"
       exit
   fi
   
   if [ -z $hostname ]
   then
       # Consider a blank name as on purpose (we can report these in various debug queries if not)
       echo "Ok"
       exit
   else
       if [ -z $ip ]
       then
           echo "Missing IP address"
           exit
       fi
   fi
   
   

    

Result:
**

In the prior beta (and going back many versions over years), these macros became blank if undefined. Now they are appearing as their text, e.g. instead of (without quotes) "" they appear as "{HOST.IP}" or "{HOST.DNS}". 

Expected:

I am unable to find any documentation that this is on purpose (though I confess I may have just missed it), but it seems incorrect, and will break people's code that presume the behavior remained the same.