pkgs/top-level/all-packages.nix, pkgs/applications/editors/emacs-23: prefer makeOverridable over getPkgConfig to customize GNU Emacs

Changed 'emacs23' expression to allow for argument overriding instead of
relying on getPkgConfig. While I was at it, I also simplified the actual build
expression a bit.

svn path=/nixpkgs/trunk/; revision=21873

pkgs/applications/editors/emacs-23/default.nix

@@ -1,22 +1,11 @@
-{ xawSupport ? true
-, xpmSupport ? true
-, dbusSupport ? true
-, xaw3dSupport ? false
-, gtkGUI ? false
-, xftSupport ? false
-, stdenv, fetchurl, ncurses, x11, libXaw ? null, libXpm ? null, Xaw3d ? null
-, pkgconfig ? null, gtk ? null, libXft ? null, dbus ? null
-, libpng, libjpeg, libungif, libtiff, librsvg, texinfo
-, gconf ? null
+{ stdenv, fetchurl, ncurses, x11, libXaw, libXpm, Xaw3d
+, pkgconfig, gtk, libXft, dbus, libpng, libjpeg, libungif
+, libtiff, librsvg, texinfo, gconf
 }:
 
-assert xawSupport -> libXaw != null;
-assert xpmSupport -> libXpm != null;
-assert dbusSupport -> dbus != null;
-assert xaw3dSupport -> Xaw3d != null;
-assert gtkGUI -> pkgconfig != null && gtk != null;
-assert xftSupport -> libXft != null && libpng != null; # libpng = probably a bug
-assert stdenv.isDarwin -> xawSupport; # fails to link otherwise
+assert (gtk != null) -> (pkgconfig != null);
+assert (libXft != null) -> libpng != null;	# probably a bug
+assert stdenv.isDarwin -> libXaw != null;	# fails to link otherwise
 
 stdenv.mkDerivation rec {
   name = "emacs-23.2";
@@ -29,19 +18,12 @@ stdenv.mkDerivation rec {
   };
 
   buildInputs = [
-    ncurses x11 texinfo
-    (if xawSupport then libXaw else null)
-    (if xpmSupport then libXpm else null)
-    (if dbusSupport then dbus else null)
-    (if xaw3dSupport then Xaw3d else null)
-    libpng libjpeg libungif libtiff librsvg
-  ]
-  ++ (if gtkGUI then [pkgconfig gtk] else [])
-  ++ (if xftSupport then [libXft] else [])
-  ++ stdenv.lib.optional (gconf != null) gconf;
+    ncurses x11 texinfo libXaw Xaw3d libXpm dbus libpng libjpeg libungif
+    libtiff librsvg gtk (if gtk != null then pkgconfig else null) libXft gconf
+  ];
 
   configureFlags =
-    stdenv.lib.optionals gtkGUI [ "--with-x-toolkit=gtk" "--with-xft" ];
+    stdenv.lib.optionals (gtk != null) [ "--with-x-toolkit=gtk" "--with-xft" ];
 
   doCheck = true;
 
@@ -68,7 +50,7 @@ stdenv.mkDerivation rec {
     homepage = http://www.gnu.org/software/emacs/;
     license = "GPLv3+";
 
-    maintainers = [ stdenv.lib.maintainers.ludo ];
+    maintainers = [ stdenv.lib.maintainers.ludo stdenv.lib.maintainers.simons ];
     platforms = stdenv.lib.platforms.all;
   };
 }

pkgs/top-level/all-packages.nix

@@ -7451,17 +7451,17 @@ let
     gtkGUI = getPkgConfig "emacs" "gtkSupport" true;
   };
 
-  emacs23 = import ../applications/editors/emacs-23 {
-    inherit fetchurl stdenv ncurses pkgconfig x11 Xaw3d
-      libpng libjpeg libungif libtiff librsvg texinfo dbus;
-    inherit (xlibs) libXaw libXpm libXft;
-    inherit (gtkLibs) gtk;
-    gconf = gnome.GConf;  # optional GConf support.
-    xawSupport = stdenv.isDarwin || getPkgConfig "emacs" "xawSupport" false;
-    xaw3dSupport = getPkgConfig "emacs" "xaw3dSupport" false;
-    gtkGUI = getPkgConfig "emacs" "gtkSupport" true;
-    xftSupport = getPkgConfig "emacs" "xftSupport" true;
-    dbusSupport = getPkgConfig "emacs" "dbusSupport" true;
+  emacs23 = makeOverridable (import ../applications/editors/emacs-23) {
+    inherit fetchurl stdenv ncurses pkgconfig x11 libpng libjpeg
+      libungif libtiff texinfo dbus;
+    inherit (xlibs) libXpm libXft;
+    # use override to select the appropriate gui toolkit
+    libXaw = if stdenv.isDarwin then xlibs.libXaw else null;
+    Xaw3d = null;
+    gtk = if stdenv.isDarwin then gtkLibs.gtk else null;
+    # TODO: these packages don't build on Darwin.
+    gconf = if stdenv.isDarwin then null else gnome.GConf;
+    librsvg = if stdenv.isDarwin then null else librsvg;
   };
 
   emacsSnapshot = lowPrio (import ../applications/editors/emacs-snapshot {