[template-glib] eval: improve typeof() to introspect boxed value

[Christian Hergert <chergert src gnome org>]

commit 2b54962455e9c7da8382d361b66d2ce88389171d
Author: Christian Hergert <chergert redhat com>
Date:   Mon Oct 23 16:28:24 2017 -0700

    eval: improve typeof() to introspect boxed value

 src/tmpl-expr-eval.c |   12 +++++++++++-
 1 files changed, 11 insertions(+), 1 deletions(-)
---
diff --git a/src/tmpl-expr-eval.c b/src/tmpl-expr-eval.c
index d456a65..cb61477 100644
--- a/src/tmpl-expr-eval.c
+++ b/src/tmpl-expr-eval.c
@@ -1562,7 +1562,17 @@ builtin_typeof (const GValue  *value,
                 GError       **error)
 {
   g_value_init (return_value, G_TYPE_GTYPE);
-  g_value_set_gtype (return_value, G_VALUE_TYPE (value));
+
+  if (G_VALUE_HOLDS (value, TMPL_TYPE_BASE_INFO) &&
+      g_value_get_pointer (value) != NULL)
+    g_value_set_gtype (return_value,
+                       g_registered_type_info_get_g_type (g_value_get_pointer (value)));
+  else if (G_VALUE_HOLDS_OBJECT (value) &&
+           g_value_get_object (value) != NULL)
+    g_value_set_gtype (return_value, G_OBJECT_TYPE (g_value_get_object (value)));
+  else
+    g_value_set_gtype (return_value, G_VALUE_TYPE (value));
+
   return TRUE;
 }