Added test to cover : add numeric + null => null

git-svn-id: https://asterixdb.googlecode.com/svn/branches/asterix_stabilization@534 eaa15691-b419-025a-1212-ee371bd00084
diff --git a/asterix-app/src/test/resources/runtimets/queries/constructor/add-null.aql b/asterix-app/src/test/resources/runtimets/queries/constructor/add-null.aql
new file mode 100644
index 0000000..caa30d7
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/queries/constructor/add-null.aql
@@ -0,0 +1,12 @@
+/*
+ * Description      :   Add anything plus null, the result should be null.
+ * Expected Result  :   Success
+ * Date             :   19th July 2012
+ */
+
+write output to nc1:"rttest/constructor_add-null.adm";
+
+let $x := 1
+let $y := 10
+let $z := 20
+return ($x+$y+$z+null)
diff --git a/asterix-app/src/test/resources/runtimets/results/constructor/add-null.adm b/asterix-app/src/test/resources/runtimets/results/constructor/add-null.adm
new file mode 100644
index 0000000..19765bd
--- /dev/null
+++ b/asterix-app/src/test/resources/runtimets/results/constructor/add-null.adm
@@ -0,0 +1 @@
+null