Add hash_unordered_set_test

test/Jamfile.v2

@@ -94,3 +94,5 @@ run hash_unordered_range_test.cpp ;
 
 run hash_unordered_multiset_test.cpp ;
 run hash_unordered_multimap_test.cpp ;
+
+run hash_unordered_set_test.cpp ;

test/hash_unordered_set_test.cpp

@@ -0,0 +1,56 @@
+// Copyright 2021, 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 8
+# pragma GCC diagnostic ignored "-Wsign-conversion"
+#endif
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/detail/splitmix64.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX11_HDR_UNORDERED_SET)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped, BOOST_NO_CXX11_HDR_UNORDERED_SET is defined" )
+int main() {}
+
+#else
+
+#include <unordered_set>
+
+template<class T> std::size_t hv( T const& x )
+{
+    return boost::hash<T>()( x );
+}
+
+template<class T> void test()
+{
+    typedef std::unordered_set<T> set;
+
+    int const N = 256;
+
+    set v;
+
+    boost::detail::splitmix64 rng;
+
+    for( int i = 0; i < N; ++i )
+    {
+        BOOST_TEST_EQ( hv( v ), boost::hash_unordered_range( v.begin(), v.end() ) );
+        v.insert( static_cast<T>( rng() ) );
+    }
+}
+
+int main()
+{
+    test<unsigned>();
+    test<boost::uint64_t>();
+    test<float>();
+    test<double>();
+
+    return boost::report_errors();
+}
+
+#endif