The SolarWinds adapter has fairly low unit test coverage:

istio.io/istio/mixer/adapter/solarwinds:48 [50.9]
istio.io/istio/mixer/adapter/solarwinds/internal/appoptics:70 [72.5]
istio.io/istio/mixer/adapter/solarwinds/internal/papertrail:55 [57.7]

Ideally, this should be at or near 100%.

Thanks.