1 files changed, 84 insertions, 0 deletions
diff --git a/test/std/thread/futures/futures.promise/swap.pass.cpp b/test/std/thread/futures/futures.promise/swap.pass.cpp
new file mode 100644
index 0000000000000..1ed3e646813c3
--- /dev/null
+++ b/test/std/thread/futures/futures.promise/swap.pass.cpp
@@ -0,0 +1,84 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: libcpp-has-no-threads
+
+// <future>
+
+// class promise<R>
+
+// void swap(promise& other);
+
+// template <class R> void swap(promise<R>& x, promise<R>& y);
+
+#include <future>
+#include <cassert>
+
+#include "../test_allocator.h"
+
+int main()
+{
+    assert(test_alloc_base::count == 0);
+    {
+        std::promise<int> p0(std::allocator_arg, test_allocator<int>());
+        std::promise<int> p(std::allocator_arg, test_allocator<int>());
+        assert(test_alloc_base::count == 2);
+        p.swap(p0);
+        assert(test_alloc_base::count == 2);
+        std::future<int> f = p.get_future();
+        assert(test_alloc_base::count == 2);
+        assert(f.valid());
+        f = p0.get_future();
+        assert(f.valid());
+        assert(test_alloc_base::count == 2);
+    }
+    assert(test_alloc_base::count == 0);
+    {
+        std::promise<int> p0(std::allocator_arg, test_allocator<int>());
+        std::promise<int> p(std::allocator_arg, test_allocator<int>());
+        assert(test_alloc_base::count == 2);
+        swap(p, p0);
+        assert(test_alloc_base::count == 2);
+        std::future<int> f = p.get_future();
+        assert(test_alloc_base::count == 2);
+        assert(f.valid());
+        f = p0.get_future();
+        assert(f.valid());
+        assert(test_alloc_base::count == 2);
+    }
+    assert(test_alloc_base::count == 0);
+    {
+        std::promise<int> p0(std::allocator_arg, test_allocator<int>());
+        std::promise<int> p;
+        assert(test_alloc_base::count == 1);
+        p.swap(p0);
+        assert(test_alloc_base::count == 1);
+        std::future<int> f = p.get_future();
+        assert(test_alloc_base::count == 1);
+        assert(f.valid());
+        f = p0.get_future();
+        assert(f.valid());
+        assert(test_alloc_base::count == 1);
+    }
+    assert(test_alloc_base::count == 0);
+    {
+        std::promise<int> p0(std::allocator_arg, test_allocator<int>());
+        std::promise<int> p;
+        assert(test_alloc_base::count == 1);
+        swap(p, p0);
+        assert(test_alloc_base::count == 1);
+        std::future<int> f = p.get_future();
+        assert(test_alloc_base::count == 1);
+        assert(f.valid());
+        f = p0.get_future();
+        assert(f.valid());
+        assert(test_alloc_base::count == 1);
+    }
+    assert(test_alloc_base::count == 0);
+}