SERVER-35818 Add stdx::variant

(cherry picked from commit 309e4bc0867988210601454750760e0d00c896ca)

1 files changed, 31 insertions, 0 deletions

diff --git a/src/third_party/variant-1.3.0/test/hash.cpp b/src/third_party/variant-1.3.0/test/hash.cpp
new file mode 100644
index 00000000000..4b4db44dbdb
--- /dev/null
+++ b/src/third_party/variant-1.3.0/test/hash.cpp
@@ -0,0 +1,31 @@
+// MPark.Variant
+//
+// Copyright Michael Park, 2015-2017
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+
+#include <mpark/variant.hpp>
+
+#include <string>
+
+#include <gtest/gtest.h>
+
+TEST(Hash, Monostate) {
+  mpark::variant<int, mpark::monostate, std::string> v(mpark::monostate{});
+  // Construct hash function objects.
+  std::hash<mpark::monostate> monostate_hash;
+  std::hash<mpark::variant<int, mpark::monostate, std::string>> variant_hash;
+  // Check the hash.
+  EXPECT_NE(monostate_hash(mpark::monostate{}), variant_hash(v));
+}
+
+TEST(Hash, String) {
+  mpark::variant<int, std::string> v("hello");
+  EXPECT_EQ("hello", mpark::get<std::string>(v));
+  // Construct hash function objects.
+  std::hash<std::string> string_hash;
+  std::hash<mpark::variant<int, std::string>> variant_hash;
+  // Check the hash.
+  EXPECT_NE(string_hash("hello"), variant_hash(v));
+}