[pkg-go] Bug#894862: dh-golang: DH_GOPKG is empty in debian/rules, while documentation states that it's automatically set

[Arnaud Rebillout]

Package: dh-golang
Version: 1.34
Severity: normal

Dear Maintainer,

According to `man dh-golang`:

  "DH_GOPKG" (string) contains the Go package name which this Debian
  package is building.

  "DH_GOPKG" is automatically set to the value of the first import path
  of the "XS-Go-Import-Path" "debian/control" field, which can contain
  several comma-separated import paths.

However, I tried to use this variable in the debian/rules file, in
targets such as `override_dh_auto_test` and `override_dh_auto_build`,
and this variable is empty.

I added some debug to dh-golang, and I clearly see the code from
`_set_dh_gopkg` being executed, and the variable is set there. So it
looks like the environment in `debian/rules` is unrelated to the
environment that is set by dh-golang.

If it's expected, then maybe the man page needs a little rewording. If
it's not expected, then it's a bug?

Regards,

  Arnaud

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.13.0-1-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages dh-golang depends on:
ii  debhelper     11.1.5
ii  dpkg          1.19.0.5
ii  libdpkg-perl  1.19.0.5
ii  perl          5.26.1-5

dh-golang recommends no packages.

dh-golang suggests no packages.

-- no debconf information