po/LINGUAS

One issue that was meantioned as a Gnome Goal was to switch packages to use a po/LINGUAS file.

The idea makes sense — translators only need to edit a simple text file to add a new translation to an application, rather than having to modify the configure.in/configure.ac file without breaking things. Unfortunately, the suggested way of supporting this is a pretty big hack. A better long term solution would be to use the upstream gettext macros and po/Makefile.in.in infrastructure.

For a Gnome module that doesn’t use intltool, the following steps should work.

  1. Make sure the module is being built with Automake 1.8 or 1.9. If it isn’t, upgrade to 1.9.
  2. Create an m4 subdirectory in your project if it doesn’t exist, add it in CVS and then create and add a m4/.cvsignore file (there are a number of files that will get created here by gettext that you don’t want to check into CVS).
  3. Mark the m4 subdirectory as the macro dir in the configure.ac file:
    AC_CONFIG_MACRO_DIR([m4])
    

    And make sure that the macro dir gets checked if the makefile reruns aclocal:

    AC_SUBST([ACLOCAL_AMFLAGS], ["-I $ac_macro_dir \${ACLOCAL_FLAGS}"])
    
  4. If you aren’t using the gnome-common autogen.sh script, you will also need to make sure that aclocal is called with “-I m4“. If you are using the gnome-common script, then this will happen automatically.
  5. Remove the AM_GLIB_GNU_GETTEXT call from configure.ac and replace it with:
    AM_GNU_GETTEXT([external])
    AM_GNU_GETTEXT_VERSION([0.14.1])
    
  6. If you aren’t using the gnome-common autogen.sh script, change the call to glib-gettextize to autopoint, and make sure it gets run before aclocal (again, unneeded if you are using the gnome-common script).
  7. Now rerun autogen.sh so that autopoint gets run. This should result in a number of files getting created under m4, and some new files under po.
  8. Copy po/Makevars.template to po/Makevars and customise the variables. You might want to set DOMAIN to $(GETTEXT_PACKAGE) rather than $(PACKAGE). Add this new file in CVS.
  9. Update po/LINGUAS from the ALL_LINGUAS variable in configure.ac, and then remove the ALL_LINGUAS definition. Add po/LINGUAS to CVS.
  10. Finally update m4/.cvsignore and po/.cvsignore to ignore the new generated files.

As I said at the start, this change is only appropriate for apps not using intltool, since intltool overwrites the po/Makefile.in.in file with an incomaptible version.

To get things working with intltool, I believe it would make most sense to modify intltool as follows:

  • Make intltool provide some commands that are command line argument compatible with xgettext and msgmerge.
  • Make IT_PROG_INTLTOOL alter XGETTEXT and MSGMERGE with the appropriate intltool functions.
  • Don’t overwrite po/Makefile.in.in.
  • If additional makefile rules are needed in the po subdirectory, install a po/Rules-intltool file containing them. The gettext M4 macros will include them into the resulting Makefile.