Imported Upstream version 2.99.2

[platform/upstream/libsigc++.git] / tests / test_tuple_transform_each.cc

diff --git a/tests/test_tuple_transform_each.cc b/tests/test_tuple_transform_each.cc
index 8830011..5e22e40 100644 (file)
--- a/tests/test_tuple_transform_each.cc
+++ b/tests/test_tuple_transform_each.cc
@@ -262,6 +262,57 @@ test_tuple_transform_each_empty_tuple() {
   sigc::internal::tuple_transform_each<transform_to_string>(t);
 }
 
+// The general template declaration.
+// We then provide specializations for each type,
+// so we can test having a different return value for each T_element_from type.
+template <class T_element_from>
+class transform_as_constexpr_to_something;
+
+// An int will be converted to a char:
+template <>
+class transform_as_constexpr_to_something<int> {
+public:
+  constexpr
+  static
+  char
+  transform(int from) {
+    return 'a' + from;
+  }
+};
+
+// A double will be converted to an int:
+template <>
+class transform_as_constexpr_to_something<const double> {
+public:
+  constexpr
+  static
+  int
+  transform(double from) {
+    return (int)from;
+  }
+};
+
+/* TODO: See the comment in main().
+constexpr
+void
+test_tuple_transform_each_constexpr() {
+  constexpr auto t_original = std::make_tuple(1, (double)2.1f);
+  constexpr auto t_transformed =
+    sigc::internal::tuple_transform_each<transform_as_constexpr_to_something>(t_original);
+  constexpr auto t_expected = std::make_tuple('b', 2);
+
+  static_assert(std::tuple_size<decltype(t_transformed)>::value == 2,
+    "unexpected tuple_transform_each()ed tuple size.");
+
+  assert(std::get<0>(t_transformed) == 'b');
+  assert(std::get<1>(t_transformed) == 2);
+
+  static_assert(
+    std::is_same<decltype(t_transformed), decltype(t_expected)>::value,
+    "unexpected transform_each()ed tuple type");
+}
+*/
+
 int
 main() {
   test_tuple_transform_each_same_types();
@@ -276,5 +327,11 @@ main() {
 
   test_tuple_transform_each_empty_tuple();
 
+  // g++ 5.2.1 gives this error:
+  //   error: accessing uninitialized member ‘std::tuple<char>::<anonymous>’
+  // though it works with clang++.
+  // TODO: Try it with a newer g++.
+  //test_tuple_transform_each_constexpr();
+
   return EXIT_SUCCESS;
 }