==== no wildcard
rcpt1@example1.com:example1.com -> channel1:nexthop1 
rcpt1+ext1@example1.com:example1.com -> channel1:nexthop1 
rcpt2@example2:example2 -> channel2:example2 
rcpt@example3:example3 -> channel3:example3 
==== with wildcard channel and nexthop
rcpt1@example1.com:example1.com -> channel1:nexthop1 
rcpt2@example2:example2 -> channel0:nexthop0 
==== with wildcard channel only
rcpt1@example1.com:example1.com -> channel1:nexthop1 
rcpt2@example2:example2 -> channel0:example2 
==== with wildcard nexthop only
rcpt1@example1.com:example1.com -> channel1:nexthop1 
rcpt2@example2:example2 -> DEFAULT:nexthop0 
==== with wildcard empty fields.
rcpt1@example1.com:example1.com -> channel1:nexthop1 
rcpt2@example2:example2 -> DEFAULT:example2 
=== subdomain test
plain1+ext@other-example:other-example -> (not found)
foo@example:example -> DEFAULT:example-result 
foo@sub.example:sub.example -> DEFAULT:dot-example-result 
foo@sub.sub.example:sub.sub.example -> DEFAULT:dot-example-result