Syslog provides logging infrastructure and corresponding tests for Fuchsia.
To add this component to your build, append --with-host-labels //sdk/lib/syslog/cpp:tests to the fx set invocation.
To run host tests, use
$ fx test --host logging_cpp_unittests
Note that host tests are not currently supported on ARM MacOS, but should function on Intel-based Macs or on certain Linux distributions.