Added failing tests for index out of range for tuple_element<pair<T1,T2>> and variant_alternative<>

llvm-svn: 306580

1 files changed, 32 insertions, 0 deletions

diff --git a/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.fail.cpp b/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.fail.cpp
new file mode 100644
index 00000000000..cbaa2a568d5
--- /dev/null
+++ b/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.fail.cpp
@@ -0,0 +1,32 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <variant>
+
+// template <size_t I, class T> struct variant_alternative; // undefined
+// template <size_t I, class T> struct variant_alternative<I, const T>;
+// template <size_t I, class T> struct variant_alternative<I, volatile T>;
+// template <size_t I, class T> struct variant_alternative<I, const volatile T>;
+// template <size_t I, class T>
+//   using variant_alternative_t = typename variant_alternative<I, T>::type;
+//
+// template <size_t I, class... Types>
+//    struct variant_alternative<I, variant<Types...>>;
+
+#include <memory>
+#include <type_traits>
+#include <variant>
+
+int main() {
+    using V = std::variant<int, void *, const void *, long double>;
+    typename std::variant_alternative<4, V>::type foo;  // expected-error@variant:* {{Index out of bounds in std::variant_alternative<>}}
+}