[libcxx] LWG2485: get() should be overloaded for const tuple&&. Patch from K-Ballo.

Review: http://reviews.llvm.org/D14839
llvm-svn: 255941

2 files changed, 111 insertions, 5 deletions

diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const_rv.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const_rv.pass.cpp
new file mode 100644
index 00000000000..edd2f3d0752
--- /dev/null
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const_rv.pass.cpp
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <utility>
+
+// template <class T1, class T2> struct pair
+
+// template<size_t I, class T1, class T2>
+//     const typename tuple_element<I, std::pair<T1, T2> >::type&&
+//     get(const pair<T1, T2>&&);
+
+// UNSUPPORTED: c++98, c++03
+
+#include <utility>
+#include <memory>
+#include <type_traits>
+#include <cassert>
+
+#include "test_macros.h"
+
+int main()
+{
+    {
+    typedef std::pair<std::unique_ptr<int>, short> P;
+    const P p(std::unique_ptr<int>(new int(3)), 4);
+    static_assert(std::is_same<const std::unique_ptr<int>&&, decltype(std::get<0>(std::move(p)))>::value, "");
+    static_assert(noexcept(std::get<0>(std::move(p))), "");
+    const std::unique_ptr<int>&& ptr = std::get<0>(std::move(p));
+    assert(*ptr == 3);
+    }
+
+    {
+    int x = 42;
+    int const y = 43;
+    std::pair<int&, int const&> const p(x, y);
+    static_assert(std::is_same<int&, decltype(std::get<0>(std::move(p)))>::value, "");
+    static_assert(noexcept(std::get<0>(std::move(p))), "");
+    static_assert(std::is_same<int const&, decltype(std::get<1>(std::move(p)))>::value, "");
+    static_assert(noexcept(std::get<1>(std::move(p))), "");
+    }
+
+    {
+    int x = 42;
+    int const y = 43;
+    std::pair<int&&, int const&&> const p(std::move(x), std::move(y));
+    static_assert(std::is_same<int&&, decltype(std::get<0>(std::move(p)))>::value, "");
+    static_assert(noexcept(std::get<0>(std::move(p))), "");
+    static_assert(std::is_same<int const&&, decltype(std::get<1>(std::move(p)))>::value, "");
+    static_assert(noexcept(std::get<1>(std::move(p))), "");
+    }
+
+#if TEST_STD_VER > 11
+    {
+    typedef std::pair<int, short> P;
+    constexpr const P p1(3, 4);
+    static_assert(std::get<0>(std::move(p1)) == 3, "");
+    static_assert(std::get<1>(std::move(p1)) == 4, "");
+    }
+#endif
+}
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type.pass.cpp
index 176d58330d1..efcc2cedc6e 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type.pass.cpp
@@ -7,15 +7,17 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: c++98, c++03, c++11
+
 #include <utility>
 #include <string>
+#include <type_traits>
 #include <complex>
 
 #include <cassert>
 
 int main()
 {
-#if _LIBCPP_STD_VER > 11
     typedef std::complex<float> cf;
     {
     auto t1 = std::make_pair<int, cf> ( 42, { 1,2 } );
@@ -23,7 +25,7 @@ int main()
     assert ( std::get<cf>(t1).real() == 1 );
     assert ( std::get<cf>(t1).imag() == 2 );
     }
-    
+
     {
     const std::pair<int, const int> p1 { 1, 2 };
     const int &i1 = std::get<int>(p1);
@@ -35,10 +37,48 @@ int main()
     {
     typedef std::unique_ptr<int> upint;
     std::pair<upint, int> t(upint(new int(4)), 42);
-    upint p = std::get<0>(std::move(t)); // get rvalue
+    upint p = std::get<upint>(std::move(t)); // get rvalue
+    assert(*p == 4);
+    assert(std::get<upint>(t) == nullptr); // has been moved from
+    }
+
+    {
+    typedef std::unique_ptr<int> upint;
+    const std::pair<upint, int> t(upint(new int(4)), 42);
+    static_assert(std::is_same<const upint&&, decltype(std::get<upint>(std::move(t)))>::value, "");
+    static_assert(noexcept(std::get<upint>(std::move(t))), "");
+    static_assert(std::is_same<const int&&, decltype(std::get<int>(std::move(t)))>::value, "");
+    static_assert(noexcept(std::get<int>(std::move(t))), "");
+    auto&& p = std::get<upint>(std::move(t)); // get const rvalue
+    auto&& i = std::get<int>(std::move(t)); // get const rvalue
     assert(*p == 4);
-    assert(std::get<0>(t) == nullptr); // has been moved from
+    assert(i == 42);
+    assert(std::get<upint>(t) != nullptr);
     }
 
-#endif
+    {
+    int x = 42;
+    int const y = 43;
+    std::pair<int&, int const&> const p(x, y);
+    static_assert(std::is_same<int&, decltype(std::get<int&>(std::move(p)))>::value, "");
+    static_assert(noexcept(std::get<int&>(std::move(p))), "");
+    static_assert(std::is_same<int const&, decltype(std::get<int const&>(std::move(p)))>::value, "");
+    static_assert(noexcept(std::get<int const&>(std::move(p))), "");
+    }
+
+    {
+    int x = 42;
+    int const y = 43;
+    std::pair<int&&, int const&&> const p(std::move(x), std::move(y));
+    static_assert(std::is_same<int&&, decltype(std::get<int&&>(std::move(p)))>::value, "");
+    static_assert(noexcept(std::get<int&&>(std::move(p))), "");
+    static_assert(std::is_same<int const&&, decltype(std::get<int const&&>(std::move(p)))>::value, "");
+    static_assert(noexcept(std::get<int const&&>(std::move(p))), "");
+    }
+
+    {
+    constexpr const std::pair<int, const int> p { 1, 2 };
+    static_assert(std::get<int>(std::move(p)) == 1, "");
+    static_assert(std::get<const int>(std::move(p)) == 2, "");
+    }
 }