This is my attempt to refactor the packages so that most of their build expression is shared. Each variant of LibreOffice gets its own subdirectory src-$variant/ where files w/ source references are stored. In the directory is also override.nix which allows you to override derivation attributes in addition to source files.

The derivation of the -fresh package doesn't change so it doesn't get rebuilt. For the -still package I believe the changes are harmless (still building it though):

-    for a in sbase scalc sdraw smath swriter simpress soffice; do
+    for a in sbase scalc sdraw smath swriter simpress soffice unopkg; do
       ln -s $out/lib/libreoffice/program/$a $out/bin/$a
     done
...
       gst_all_1.gst-plugins-base glib libmysqlclient
-      neon nspr nss openldap openssl ORBit2 pam perl poppler
+      neon nspr nss openldap openssl ORBit2 pam perl pkgconfig poppler
       python3 sane-backends unzip vigra which zip zlib

Motivation for this change

• The expressions are almost identical
• I'm trying to package LibreOffice Online which may introduce the need to build yet another variant - Collabora maintains their own branch for it

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nix-review --run "nix-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

Notify maintainers

cc @7c6f434c @peterhoeg