[vala/wip/issue/606: 612/612] WIP build: Check for valac with sufficient GIR support

[Rico Tzschichholz <ricotz src gnome org>]

commit e8338f029f191c7666847dd517740dbb30599028
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Wed May 1 12:46:36 2019 +0200

    WIP build: Check for valac with sufficient GIR support

 configure.ac | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
---
diff --git a/configure.ac b/configure.ac
index 285ad899b..1370dc54e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -148,6 +148,23 @@ AC_SUBST(TEST_CFLAGS)
 
 GOBJECT_INTROSPECTION_CHECK([1.48.0])
 
+if test x$enable_introspection = xyes; then
+       AC_MSG_CHECKING([for sufficient GIR support])
+       #FIXME Adjust on merge, maybe 0.49.1
+       VALAC_GIR_REQUIRED=0.48.2.147
+
+       AS_IF([test "$VALAC" != valac], [FOUND_VALAC_VERION=`$VALAC --version | sed 's/Vala  *//'`
+               AS_VERSION_COMPARE(["$VALAC_GIR_REQUIRED"], ["$FOUND_VALAC_VERION"],
+                       [enable_gir=yes], [enable_gir=yes], [enable_gir=no])])
+
+       if test x$enable_gir = xno; then
+               AM_CONDITIONAL(HAVE_INTROSPECTION, false)
+               AC_MSG_RESULT([no (valac >= $VALAC_GIR_REQUIRED is required)])
+       else
+               AC_MSG_RESULT([yes])
+       fi
+fi
+
 GLIB_REQUIRED=2.48.0
 LIBGVC_REQUIRED=2.16