Add support for tuple-like types. Refs #30.

test/hash_tuple_like_test.cpp

@@ -0,0 +1,204 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__clang__)
+# pragma clang diagnostic ignored "-Wmismatched-tags"
+#endif
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/type_traits/enable_if.hpp>
+#include <boost/type_traits/is_same.hpp>
+#include <boost/type_traits/integral_constant.hpp>
+#include <boost/config.hpp>
+#include <utility>
+
+#if !defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+# include <tuple>
+
+namespace user
+{
+
+struct Y1
+{
+    int a;
+    int b;
+};
+
+template<std::size_t I> int& get( Y1& v );
+template<std::size_t I> int const& get( Y1 const& v );
+
+template<> int& get<0>( Y1& v )
+{
+    return v.a;
+}
+
+template<> int const& get<0>( Y1 const& v )
+{
+    return v.a;
+}
+
+template<> int& get<1>( Y1& v )
+{
+    return v.b;
+}
+
+template<> int const& get<1>( Y1 const& v )
+{
+    return v.b;
+}
+
+struct Y2
+{
+    int a;
+    int b;
+
+    template<class T> friend
+        typename boost::enable_if_<boost::is_same<T, Y2>::value, std::size_t>::type
+        hash_value( T const& v )
+    {
+        std::size_t seed = 0;
+
+        boost::hash_combine( seed, v.a );
+        boost::hash_combine( seed, v.b );
+
+        return seed;
+    }
+};
+
+} // namespace user
+
+namespace std
+{
+
+template<> struct tuple_size<user::Y1>: std::integral_constant<std::size_t, 2>
+{
+};
+
+template<> struct tuple_size<user::Y2>: std::integral_constant<std::size_t, 2>
+{
+};
+
+} // namespace std
+
+namespace boost
+{
+namespace container_hash
+{
+
+    template<> struct is_tuple_like<user::Y2>: boost::false_type {};
+
+} // namespace container_hash
+} // namespace boost
+
+#endif
+
+template<class T> std::size_t hv( T const& t )
+{
+    return boost::hash<T>()( t );
+}
+
+int main()
+{
+    {
+        std::pair<int, int> tp( 1, 2 );
+        int const a[] = { 1, 2 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+#if !defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+    {
+        std::tuple<> tp;
+
+        BOOST_TEST_EQ( hv(tp), 0u );
+    }
+
+    {
+        std::tuple<int> tp( 1 );
+        int const a[] = { 1 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int> tp( 1, 2 );
+        int const a[] = { 1, 2 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int> tp( 1, 2, 3 );
+        int const a[] = { 1, 2, 3 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int> tp( 1, 2, 3, 4 );
+        int const a[] = { 1, 2, 3, 4 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int> tp( 1, 2, 3, 4, 5 );
+        int const a[] = { 1, 2, 3, 4, 5 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int, int> tp( 1, 2, 3, 4, 5, 6 );
+        int const a[] = { 1, 2, 3, 4, 5, 6 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int, int, int> tp( 1, 2, 3, 4, 5, 6, 7 );
+        int const a[] = { 1, 2, 3, 4, 5, 6, 7 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int, int, int, int> tp( 1, 2, 3, 4, 5, 6, 7, 8 );
+        int const a[] = { 1, 2, 3, 4, 5, 6, 7, 8 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int, int, int, int, int> tp( 1, 2, 3, 4, 5, 6, 7, 8, 9 );
+        int const a[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1800)
+
+    {
+        user::Y1 tp = { 1, 2 };
+        int const a[] = { 1, 2 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+#endif
+
+    {
+        user::Y2 tp = { 1, 2 };
+        int const a[] = { 1, 2 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+#endif
+
+    return boost::report_errors();
+}