dh_installman ruins man pages on Minimal Ubuntu

[Robin Gustafsson]

`dh_installman` uses the `man` program to convert man pages to UTF-8. On Minimal Ubuntu images (18.10 and above), /usr/bin/man is replaced by a shell script outputting a notice about the lack of man pages and the option to "unminimize" the image. Thus, instead of recoding the man pages, it replaces all man pages with this output.

See for example this bug reported against Docker: <https://github.com/docker/for-linux/issues/639>

This has been observed on the minimal versions of cosmic and disco, but is likely equally applicable to the minimal version of eoan since it, too, includes the /usr/bin/man replacement.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Kir Kolyshkin (kolyshkin)]

I guess that debhelper post-install script should at least do this (taken from "/usr/local/sbin/unminimize"):

if [ "$(dpkg-divert --truename /usr/bin/man)" = "/usr/bin/man.REAL" ]; then \
       rm -f /usr/bin/man; \
       dpkg-divert --quiet --remove --rename /usr/bin/man; \
fi