netgo | Netgo is a network synchronization engine

I am trying to create an image based on this dockerfile:

https://github.com/99designs/aws-vault/blob/master/Dockerfile

Here are the 3 steps I followed:

Per doc https://cloud.google.com/cloud-build/docs/configuring-builds/substitute-variable-values

I supposed to pull $BRANCH_NAME but somehow it is not consistent. Sometimes it shows repo name and sometimes is nothing.

Here is my step

Facing error with "cannot find lpcap" for make command for some package, although I have already installed libpcap.devel.

I want to build a Go 1.9.2 binary and run it on the Docker Alpine image. The Go code I wrote doesn't call any C code. It also uses the net package. Unfortunately it hasn't been as simple as it sounds as Go doesn't seem to quite build static binaries all the time. When I try to execute the binary I often get cryptic messages for why the binary didn't execute. There's quite a bit of information on the internet about this but most of it ends up with people using trial an error to make their binaries work.

So far I have found the following works, however I don't know why, if it is optimal or if it could be simplified.

I have a test function TestJobqueue() in https://github.com/VertebrateResequencing/wr/blob/develop/jobqueue/jobqueue_test.go that I can call in isolation: go test -tags netgo ./jobqueue -v -run 'TestJobqueue$'.

I recently started getting test failures related to boltdb (one of my dependencies) bombing out with signal SIGBUS: bus error code panics, or just normally failing tests because the database couldn't be opened. But only when working off an NFS mounted directory. Fair enough, I or boltdb have some kind of NFS-related bug.

But the thing I can't wrap my head around is that I only get these errors when an entirely different test function exists.

As per the comments in TestREST() in https://github.com/VertebrateResequencing/wr/blob/92fb61ccd7819c8f1edfa8cce8468c4250d40ea7/jobqueue/rest_test.go, if I call Serve(serverConfig) (a function in the package being tested, a function call which is made many times in TestJobqueue() and other test functions) in that test function, TestJobqueue() fails. If I don't, it doesn't.

In short, the failure of tests in one test function can be controlled by the value of a boolean in a test function that I'm not running.

How is this possible?

Edit: to address some points brought up by the first answer, TestJobqueue() is being run in isolation. No other test runs before or after it. If the database file already exists, Serve() results in those files being deleted first, then a new one created to run the new set of tests. The odd thing that I'm seeking an answer for is how an unexecuted function can have this side effect. I can demonstrate it is really unexecuted by beginning or ending TestREST() with a panic call: the output of that panic is never seen, but TestJobqueue() failure can still be controlled by the boolean in TestREST() (if the panic comes at the end).

Edit2: this turns out to be caused by an unusual thing I do in TestJobqueue(), which is to call go test on itself. Needless to say, if you do this, strange things can happen...