[gnome-code-assistance] [backends/vala] Support multiple versions of libvala-2.x

[Jesse van den Kieboom <jessevdk src gnome org>]

commit 577ed21fdf3972bccac03c1cc4a0b5647073a15a
Author: Jesse van den Kieboom <jessevdk gmail com>
Date:   Mon Nov 11 17:17:26 2013 +0100

    [backends/vala] Support multiple versions of libvala-2.x

 backends/vala/Makefile.am |    2 +-
 configure.ac              |   26 ++++++++++++++++++++++++--
 2 files changed, 25 insertions(+), 3 deletions(-)
---
diff --git a/backends/vala/Makefile.am b/backends/vala/Makefile.am
index 9e48723..e7674d5 100644
--- a/backends/vala/Makefile.am
+++ b/backends/vala/Makefile.am
@@ -13,7 +13,7 @@ backends_vala_vala_VALAFLAGS =                        \
        --target-glib=2.36                      \
        --pkg gio-2.0                           \
        --pkg gee-0.8                           \
-       --pkg libvala-0.22
+       --pkg $(BACKEND_VALA_LIBVALA)
 
 backends_vala_vala_CFLAGS = $(BACKEND_VALA_CFLAGS) -w
 backends_vala_vala_LDADD = $(BACKEND_VALA_LIBS)
diff --git a/configure.ac b/configure.ac
index 1b83035..0f4a643 100644
--- a/configure.ac
+++ b/configure.ac
@@ -300,7 +300,29 @@ AC_ARG_ENABLE([vala],
               [enable_vala=$enableval],
               [enable_vala=auto])
 
-BACKEND_VALA_MODULES="gobject-2.0 >= 2.36 glib-2.0 >= 2.36 gio-2.0 >= 2.36 gee-0.8 libvala-0.22"
+BACKEND_VALA_LIBVALA_VERSIONS="libvala-0.22 libvala-0.20"
+BACKEND_VALA_MODULES="gobject-2.0 >= 2.36 glib-2.0 >= 2.36 gio-2.0 >= 2.36 gee-0.8"
+
+BACKEND_VALA_LIBVALA=
+for i in $BACKEND_VALA_LIBVALA_VERSIONS; do
+       if test "x$BACKEND_VALA_LIBVALA" = "x"; then
+               BACKEND_VALA_LIBVALA="$i"
+       fi
+
+       PKG_CHECK_EXISTS([$i], [libvala_found=yes], [libvala_found=no])
+
+       if test "x$libvala_found" = "xyes"; then
+               BACKEND_VALA_LIBVALA="$i"
+               BACKEND_VALA_MODULES="$BACKEND_VALA_MODULES $BACKEND_VALA_LIBVALA"
+               break
+       fi
+done
+
+if test "x$libvala_found" != "xyes"; then
+       BACKEND_VALA_MODULES="$BACKEND_VALA_MODULES $BACKEND_VALA_LIBVALA"
+fi
+
+AC_SUBST(BACKEND_VALA_LIBVALA)
 
 if test "x$enable_vala" != "xno"; then
        AM_PROG_VALAC
@@ -338,7 +360,7 @@ fi
 color_enable_var("$enable_vala", [enable_vala_msg])
 
 AM_CONDITIONAL(BACKENDS_VALA_ENABLE, test "x$enable_vala" = "xyes")
-
+AC_SUBST(BACKEND_VALA_LIBVALA)
 
 
 dnl ================================================================