[Pkg-zsh-devel] Bug#934926: update

[Frank Terbeck]

Daniel Shahaf wrote:
[…]
> - Packages that are part of Debian should install to
>   /usr/share/zsh/vendor-*.
>
> - Upstream packages have three options:
>
>   + Install to /usr/local/share/zsh/site-functions (regardless of their
>     own $PREFIX _and_ of zsh's $PREFIX)

This is precisely  the right fpath entry for site  local function files.
The Debian package set this to a /usr/local directory even when configu-
red with --prefix=/usr since before the current team took over.

This  is the  right thing  to do  in any  case, since  non-package files
should just be dropped into /usr/share/.

We  *added* the  ‘vendor-*’ directories  to get  fpath entries  that are
under the control of the package  system for packages to drop additional
functions into. It's been this way since about 2011.

A couple of years later (2014-ish) zsh upstream changed its compile time
configuration semantics  with respect  to site-function  directories: It
now ensures  that /usr/local/share/zsh/site-functions is  *always* there
and on top of the fpath variable.

This acknowledges  that /usr/local/  is the right  place for  site local
additions, which I don't think anybody disputes.

The change  in handling site-function  directories is that  compile time
configuration  also  adds a  PREFIX/share/zsh/site-functions  directory,
with lower priority than the one in /usr/local.

The reason  this doesn't  get added  on Debian right  now is  that we're
still  setting ‘--enable-site-fndir=/usr/local/share/zsh/site-functions’
explicitly. Dropping this setting would change this.

Since  Debian's ‘vendor-*’  directory handling  predates this  by years,
changing this,  effectively adding  a second path  for the  same purpose
seems inelegant, since it adds redundancy where none is needed.

This however, sucks:

% apt-file search usr/share/zsh/site-functions/ | wc -l
30

Because that is thirty functions that will not work.

When we  added the ‘vendor-*’ stuff,  we filed bug reports  for packages
that  tried this,  because  even  back then,  it  wouldn't have  worked,
because site-functions always was in /usr/local with Debian's zsh.

That resulted in this:

% apt-file search vendor-completions | wc -l
166


I am  not sure if  there's an elegant way  to resolve this,  because the
‘vendor-*’ directories  are the documented  way for zsh packages  to add
functions for more than a decade. I  don't think dropping them is a good
idea, because it would break backward compatibility. And as I said, just
adding the second  --prefix based site-functions entry  would litter the
system by added multiple destinations for the same purpose.

Maybe there's a way to add a  lintian check for the installation path of
zsh function files in Debian packages.  With that, we could add the pre-
fix based  site-functions directory,  but deprecate  its use.  That way,
packages  that disrespect  the zsh  package's policy  still work,  while
keeping the possibility of a clean system, in case all package adhere to
the policy. We could file a bunch of bugs for the packages that are cur-
rently using /usr/share/zsh/site-functions right now.


Regards, Frank