Bug#42634: PROPOSAL] Automatic migration to /usr/share/doc

[Ian Jackson <ian@davenant.greenend.org.uk>]

Mike Goldman writes ("Bug#42634: [PROPOSAL] Automatic migration to /usr/share/doc"):
> Package: debian-policy
> Version: 3.0.1.0
> 
> Following up my objection to #42477, I propose the following transitional
> plan for migrating files from /usr/doc to /usr/share/doc when potato
> releases.
> 
> 1.  Base-files should be modified to execute a script, automatically
> migrating all directories in /usr/doc to /usr/share/doc.  In their place,
> a README file should be installed in /usr/doc advising users where the
> new docs can be found.
> 
> 2.  Dpkg should directly or via a script, at installation of a package
> with files in /usr/doc/<package>, migrate them automatically to
> /usr/share/doc/<package>.
> 
> I volunteer to provide these scripts if desired.

Instead, I propose that:

* Any dpkg bug in this area be fixed.  If I can figure out what people
claim the bug is I'll fix it.  (I won't build an NMU, but we seem to
have no shortage of people willing to do dpkg NMUs.)

* Existing packages which use /usr/share/doc, and all new packages
which do so, should be made to contain a predepends on the base-files
I mention below.

* Base-files should be changed.  The preinst should check to see if
both exist, and:
 - if they do and have different contents it could print a warning.
 - if only /usr/doc exists it should be renamed to /usr/share/doc and
   a symlink left behind
 - if only /usr/doc exists but /usr/share is a different fs, it
   should make the reverse symlink.

The effect would be that people who installed preemptive packages from
unstable would have both a /usr/share/doc and a /usr/doc until all the
packages were migrated (or they moved them themselves); other people
would get a nice transition if they had different filesystems, or
could move it themselves if a mount point is involved.

Ian.