GO ports: Makefile do-test: 'make test'

Hello,

Recently I adopted a GO port sysutils/siegfried
<https://www.freshports.org/sysutils/siegfried/> and it as very nice
feature:
---
do-test:
        @cd ${WRKSRC} && \
                ${SETENV} ${MAKE_ENV} ${GO_ENV} ${GO_CMD} test
${GO_BUILDFLAGS} \
                ./cmd/sf
---
URL: https://github.com/richardlehane/siegfried

Running 'make test' in a interactive poudriere jail gives me extra tests
and results.

My question is: how do I know if a GO project have or not this tests
feature?
I can undertand 'do-test:' that tells to execute 'test' on .cmd/sf source
directory.

Once I understand the mechanics I can investigate "my" GO ports and see if
I can add this feature to them.

Thanks,

Nuno Teixeira