You likely have the newer `lua @5.3.4_1` installed, and it's trampling
the `lua52 @5.2.4_1` installation. If you deactivate `lua`, you should be
able to install `wireshark2 +lua`:
$ port -v installed wireshark2
The following ports are currently installed:
(active) platform='darwin 18' archs='x86_64'
To fix this, `wireshark2` needs to have the `lua-5.2` include directory
included AHEAD of the system include directories in it's `CMakeLists.txt`
file. This is a modest PITA to do, but there are plenty of examples in the
macports repo of this being done.
`wireshark2` is not presently compatible with `lua @5.3.4_1`, at least
with the current versions in MacPorts.
wireshark2: fix build with +lua when lua5.3 is installed