Bug#844512: reprotest: make diffoscope optional

[Ximin Luo]

Package: reprotest
Version: 0.3.2
Severity: wishlist

Dear Maintainer,

It would be good to make diffoscope optional. Sometimes for various reasons a
developer might want to run reprotest inside a container/chroot/environment
where they don't want to install diffoscope. Then reprotest should save the
build output so the user can copy it to a system that does have diffoscope.

For example I have access to a remote jessie machine, so I have to run all my
builds inside a schroot already. Inside the schroot I run reprotest with a null
virtual server, but I don't want diffoscope's dependencies to possibly affect
the build.

(Yes I could use another schroot inside the schroot but I have a feeling this
wouldn't work so well and I'd rather not spend time debugging it. Also this
would not be possible on Debian porter machines where we don't have root to be
able to set up the inner schroots.)

X

-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'stable'), (300, 'unstable'), (200, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.7.0-1-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)

Versions of packages reprotest depends on:
ii  apt-utils              1.3.1
ii  diffoscope             62
ii  libdpkg-perl           1.18.10
ii  procps                 2:3.3.12-2
ii  python3-debian         0.1.29
ii  python3-pkg-resources  28.0.0-1
pn  python3:any            <none>

Versions of packages reprotest recommends:
ii  autodep8     0.8
ii  disorderfs   0.5.1-1
ii  locales-all  2.24-5
ii  qemu-system  1:2.7+dfsg-3
ii  qemu-utils   1:2.7+dfsg-3
ii  schroot      1.6.10-2+b1

reprotest suggests no packages.

-- no debconf information