Bug#821031: glib2.0: autopkgtests fail if gvfs is installed: stderr: Activating service name='org.gtk.vfs.Daemon'

[Simon McVittie]

Source: glib2.0
Version: 2.48.0-1
Severity: normal

While working on glib2.0 in a Debian derivative I noticed that on my
development virtual machine, which has gvfs installed, the autopkgtests
fail under sadt(1). This can be reproduced in real Debian like this:

    adt-run --setup-commands="apt-get update; apt-get -y dist-upgrade; apt-get -y install gvfs" -U --apt-source glib2.0 --- qemu adt-sid.qcow2c

where adt-sid.qcow2c is an autopkgtest virtual machine prepared according
to the vmdebootstrap instructions in adt-virt-qemu(1). If I don't add
gvfs, the tests pass.

The failure appears to be because the tests' use of dbus-run-session
results in the dbus-daemon's log messages going to stderr, and by default
autopkgtest considers any output on stderr to be a failure. It logs:

    FAIL stderr: Activating service name='org.gtk.vfs.Daemon'

Adding --env=GIO_USE_VFS=local to the adt-run command-line should resolve
this, suggesting that debian/tests/installed-tests should maybe export
that environment variable for better robustness - these tests aren't
meant to exercise gvfs anyway, otherwise they'd depend on it.

Alternatively, or perhaps additionally, debian/tests/control could
configure stderr to be ignored - we know that the GLib installed-tests
are well-behaved (exit nonzero on error), so we don't have to
screen-scrape stderr to find out about failures.

-- System Information:
Debian Release: stretch/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.5.0-trunk-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)