This repository holds a Go module that demonstrates an oddity of the Go tool's test runner. The way tests with sub-processes is handled differs depending on whether or not you specify the package name on the command line.

The run.sh script demonstrates this:

$ ./run.sh
This one waits for the sub-process to exit before exiting.
+ go test -v -count=1 .
=== RUN   TestHang
--- PASS: TestHang (0.00s)
PASS
HANG
ok  	github.com/adg/hang	5.511s
This one returns instantly, but the sub-process is still running.
+ go test -v -count=1
=== RUN   TestHang
--- PASS: TestHang (0.00s)
PASS
ok  	github.com/adg/hang	0.095s

Note that the only difference between the go test invocations is the presence of the package name (. in this case).

See the test source code for the details.