Implement N3672, optional<T>.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@189772 91177308-0d34-0410-b5e6-96231b3b80d8

test/utilities/optional/optional.object/optional.object.ctor/move.pass.cpp

@@ -0,0 +1,122 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <optional>
+
+// optional(optional<T>&& rhs) noexcept(is_nothrow_move_constructible<T>::value);
+
+#include <optional>
+#include <type_traits>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+template <class T>
+void
+test(std::optional<T>& rhs, bool is_going_to_throw = false)
+{
+    static_assert(std::is_nothrow_move_constructible<std::optional<T>>::value ==
+                  std::is_nothrow_move_constructible<T>::value, "");
+    bool rhs_engaged = static_cast<bool>(rhs);
+    try
+    {
+        std::optional<T> lhs = std::move(rhs);
+        assert(is_going_to_throw == false);
+        assert(static_cast<bool>(lhs) == rhs_engaged);
+    }
+    catch (int i)
+    {
+        assert(i == 6);
+    }
+}
+
+class X
+{
+    int i_;
+public:
+    X(int i) : i_(i) {}
+    X(X&& x) : i_(x.i_) {x.i_ = 0;}
+    ~X() {i_ = 0;}
+    friend bool operator==(const X& x, const X& y) {return x.i_ == y.i_;}
+};
+
+class Y
+{
+    int i_;
+public:
+    Y(int i) : i_(i) {}
+    Y(Y&& x) noexcept : i_(x.i_) {x.i_ = 0;}
+
+    friend constexpr bool operator==(const Y& x, const Y& y) {return x.i_ == y.i_;}
+};
+
+int count = 0;
+
+class Z
+{
+    int i_;
+public:
+    Z(int i) : i_(i) {}
+    Z(Z&&)
+    {
+        if (++count == 2)
+            throw 6;
+    }
+
+    friend constexpr bool operator==(const Z& x, const Z& y) {return x.i_ == y.i_;}
+};
+
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    {
+        typedef int T;
+        std::optional<T> rhs;
+        test(rhs);
+    }
+    {
+        typedef int T;
+        std::optional<T> rhs(3);
+        test(rhs);
+    }
+    {
+        typedef X T;
+        std::optional<T> rhs;
+        test(rhs);
+    }
+    {
+        typedef X T;
+        std::optional<T> rhs(X(3));
+        test(rhs);
+    }
+    {
+        typedef Y T;
+        std::optional<T> rhs;
+        test(rhs);
+    }
+    {
+        typedef Y T;
+        std::optional<T> rhs(Y(3));
+        test(rhs);
+    }
+    {
+        typedef Z T;
+        std::optional<T> rhs;
+        test(rhs);
+    }
+    {
+        typedef Z T;
+        std::optional<T> rhs(Z(3));
+        test(rhs, true);
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}