Building package form source fails when deploying to xenial

[Björn Tillenius]

The landscape charm allows you to supply a source tarball, from which a binary package will be build and installed.

This no longer works on xenial, with the following error in the log:

2016-06-27 08:59:59 INFO upgrade dpkg-buildpackage: full upload; Debian-native package (full source is included)
2016-06-27 08:59:59 INFO upgrade
2016-06-27 08:59:59 INFO upgrade Traceback (most recent call last):
2016-06-27 08:59:59 INFO upgrade File "/var/lib/juju/agents/unit-landscape-server-2/charm/actions/upgrade", line 9, in <module>
2016-06-27 08:59:59 INFO upgrade sys.exit(action())
2016-06-27 08:59:59 INFO upgrade File "/var/lib/juju/agents/unit-landscape-server-2/charm/actions/lib/action.py", line 33, in __call__
2016-06-27 08:59:59 INFO upgrade return_values = self._run()
2016-06-27 08:59:59 INFO upgrade File "/var/lib/juju/agents/unit-landscape-server-2/charm/actions/lib/upgrade.py", line 32, in _run
2016-06-27 08:59:59 INFO upgrade apt.set_sources(force_update=True)
2016-06-27 08:59:59 INFO upgrade File "/var/lib/juju/agents/unit-landscape-server-2/charm/actions/lib/apt.py", line 80, in set_sources
2016-06-27 08:59:59 INFO upgrade if self._set_local_source():
2016-06-27 08:59:59 INFO upgrade File "/var/lib/juju/agents/unit-landscape-server-2/charm/actions/lib/apt.py", line 228, in _set_local_source
2016-06-27 08:59:59 INFO upgrade BUILD_LOCAL_ARCHIVE.format(epoch), shell=True, cwd=build_dir)
2016-06-27 08:59:59 INFO upgrade File "/usr/lib/python2.7/subprocess.py", line 574, in check_output
2016-06-27 08:59:59 INFO upgrade raise CalledProcessError(retcode, cmd, output=output)
2016-06-27 08:59:59 INFO upgrade subprocess.CalledProcessError: Command '
2016-06-27 08:59:59 INFO upgrade dch -v 1000:$(dpkg-parsechangelog|grep ^Version:|cut -d ' ' -f 2) development --distribution $(lsb_release -cs) &&
2016-06-27 08:59:59 INFO upgrade dpkg-buildpackage -us -uc &&
2016-06-27 08:59:59 INFO upgrade mv ../*.deb . &&
2016-06-27 08:59:59 INFO upgrade dpkg-scanpackages -m . /dev/null > Packages &&
2016-06-27 08:59:59 INFO upgrade cat Packages | bzip2 -9 > Packages.bz2 &&
2016-06-27 08:59:59 INFO upgrade cat Packages | gzip -9 > Packages.gz &&
2016-06-27 08:59:59 INFO upgrade dpkg-scansources . > Sources &&
2016-06-27 08:59:59 INFO upgrade cat Sources | bzip2 -9 > Sources.bz2 &&
2016-06-27 08:59:59 INFO upgrade cat Sources | gzip -9 > Sources.gz &&
2016-06-27 08:59:59 INFO upgrade apt-ftparchive release . > Release
2016-06-27 08:59:59 INFO upgrade ' returned non-zero exit status 255

Looking closer, it turns out it's the dpkg-scanpackages call that is failing:

root@juju-machine-0-lxc-9:/var/lib/juju/agents/unit-landscape-server-2/charm/build/package# dpkg-scanpackages .
/var/lib/juju/agents/unit-landscape-server-2/charm/build/package/src/landscape/canonical/landscape/static/fonts/ encountered a second time at /usr/share/perl/5.22/File/Find.pm line 103.