fix(interactive): Fix bug of IS_NULL check for edge property (#4386)

Fix #4384

Author: zhanglei1949

flex/engines/graph_db/runtime/adhoc/expr_impl.cc

@@ -206,6 +206,9 @@ RTAny UnaryLogicalExpr::eval_edge(const LabelTriplet& label, vid_t src,
   if (logic_ == common::Logical::NOT) {
     return RTAny::from_bool(
         !expr_->eval_edge(label, src, dst, data, idx).as_bool());
+  } else if (logic_ == common::Logical::ISNULL) {
+    return RTAny::from_bool(
+        expr_->eval_edge(label, src, dst, data, idx, 0).is_null());
   }
   LOG(FATAL) << "not support" << static_cast<int>(logic_);
   return RTAny::from_bool(false);

flex/engines/graph_db/runtime/common/rt_any.cc

@@ -119,6 +119,8 @@ RTAny::RTAny(const Any& val) {
   } else if (val.type == PropertyType::Bool()) {
     type_ = RTAnyType::kBoolValue;
     value_.b_val = val.AsBool();
+  } else if (val.type == PropertyType::Empty()) {
+    type_ = RTAnyType::kNull;
   } else {
     LOG(FATAL) << "Any value: " << val.to_string()
                << ", type = " << val.type.type_enum;
@@ -355,6 +357,8 @@ std::string_view RTAny::as_string() const {
     return value_.str_val;
   } else if (type_ == RTAnyType::kUnknown) {
     return std::string_view();
+  } else if (type_ == RTAnyType::kNull) {
+    return std::string_view();
   } else {
     LOG(FATAL) << "unexpected type" << static_cast<int>(type_.type_enum_);
     return std::string_view();

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/cypher/integration/suite/movie/MovieQueries.java

@@ -399,4 +399,10 @@ public static QueryContext get_movie_query28_test() {
         List<String> expected = Arrays.asList("Record<{typeA: \"Person\", typeC: \"Movie\"}>");
         return new QueryContext(query, expected);
     }
+
+    public static QueryContext get_movie_query29_test() {
+        String query = "MATCH(a)-[r]->(b) where r.rating is null return count(r) as count;";
+        List<String> expected = Arrays.asList("Record<{count: 249}>");
+        return new QueryContext(query, expected);
+    }
 }

interactive_engine/compiler/src/test/java/com/alibaba/graphscope/cypher/integration/movie/MovieTest.java

@@ -218,6 +218,13 @@ public void run_movie_query28_test() {
         Assert.assertEquals(testQuery.getExpectedResult().toString(), result.list().toString());
     }
 
+    @Test
+    public void run_movie_query29_test() {
+        QueryContext testQuery = MovieQueries.get_movie_query29_test();
+        Result result = session.run(testQuery.getQuery());
+        Assert.assertEquals(testQuery.getExpectedResult().toString(), result.list().toString());
+    }
+
     @AfterClass
     public static void afterClass() {
         if (session != null) {