Handle apply_not_equals.

src/filter.cpp

@@ -459,6 +459,23 @@ bool filter_result_iterator_t::valid(uint32_t id) {
         }
     }
 
+    if (filter_node->filter_exp.apply_not_equals) {
+        // Even when iterator becomes invalid, we keep it marked as valid since we are evaluating not equals.
+        if (!valid()) {
+            is_valid = true;
+            return is_valid;
+        }
+
+        skip_to(id);
+
+        if (!is_valid) {
+            is_valid = true;
+            return is_valid;
+        }
+
+        return doc != id;
+    }
+
     skip_to(id);
     return is_valid && doc == id;
 }

test/filter_test.cpp

@@ -256,7 +256,22 @@ TEST_F(FilterTest, FilterTreeIterator) {
         ASSERT_TRUE(iter_validate_ids_test.valid(i));
     }
 
-    ASSERT_FALSE(iter_skip_complex_filter_test.valid());
+    ASSERT_TRUE(iter_op.ok());
+
+    delete filter_tree_root;
+    filter_tree_root = nullptr;
+    filter_op = filter::parse_filter_query("name: James || tags: != gold", coll->get_schema(), store, doc_id_prefix,
+                                           filter_tree_root);
+    ASSERT_TRUE(filter_op.ok());
+
+    auto iter_validate_ids_not_equals_filter_test = filter_result_iterator_t(coll->get_name(), coll->_get_index(),
+                                                                             filter_tree_root, iter_op);
+
+    expected = {1, 3, 5};
+    for (auto const& i : expected) {
+        ASSERT_TRUE(iter_validate_ids_not_equals_filter_test.valid(i));
+    }
+
     ASSERT_TRUE(iter_op.ok());
 
     delete filter_tree_root;