1 files changed, 75 insertions, 0 deletions
diff --git a/compiler/loco/src/ADT/AnnotatedItem.test.cpp b/compiler/loco/src/ADT/AnnotatedItem.test.cpp
new file mode 100644
index 000000000..42113ff7b
--- /dev/null
+++ b/compiler/loco/src/ADT/AnnotatedItem.test.cpp
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2019 Samsung Electronics Co., Ltd. All Rights Reserved
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "loco/ADT/AnnotatedItem.h"
+
+#include <gtest/gtest.h>
+#include <stdex/Memory.h>
+
+namespace
+{
+
+struct Annotation
+{
+  virtual ~Annotation() = default;
+};
+
+template <int N> struct DerivedAnnotation final : public Annotation
+{
+  static std::unique_ptr<DerivedAnnotation<N>> make(void)
+  {
+    return stdex::make_unique<DerivedAnnotation<N>>();
+  }
+};
+
+} // namespace
+
+TEST(AnnotatedItemTest, annotation)
+{
+  loco::AnnotatedItem<::Annotation> item;
+
+  ASSERT_EQ(item.annot<DerivedAnnotation<0>>(), nullptr);
+
+  item.annot(DerivedAnnotation<0>::make());
+
+  ASSERT_NE(item.annot<DerivedAnnotation<0>>(), nullptr);
+  ASSERT_EQ(item.annot<DerivedAnnotation<1>>(), nullptr);
+
+  item.annot<DerivedAnnotation<0>>(nullptr);
+  ASSERT_EQ(item.annot<DerivedAnnotation<0>>(), nullptr);
+
+  // Below check guarantees that "annot<T>(nullptr)" is allowed even when there is no annotation.
+  // This guarantee allows us to simplify code for some cases.
+  //
+  // Let us consider the following example:
+  //
+  // void f(loco::AnnotatedItem<T> *item)
+  // {
+  //   /* DO SOMETHING */
+  //   if (cond) { item->annot<T>(nullptr);
+  // }
+  //
+  // void g(loco::AnnotatedItem<T> *item)
+  // {
+  //   f(item);
+  //   item->annot<T>(nullptr);
+  // }
+  //
+  // The implementation of "g" gets complicated if annot<T>(nullptr) is not allowed if there is
+  // no annotation.
+  //
+  item.annot<DerivedAnnotation<0>>(nullptr);
+}