Added tests for adapted empty struct.

test/sequence/define_struct_inline_empty.cpp

@@ -0,0 +1,75 @@
+/*=============================================================================
+    Copyright (c) 2016 Kohei Takahashi
+
+    Distributed under the Boost Software License, Version 1.0. (See accompanying
+    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+==============================================================================*/
+
+#include <boost/detail/lightweight_test.hpp>
+#include <boost/fusion/container.hpp>
+#include <boost/fusion/sequence.hpp>
+#include <boost/fusion/sequence/io/out.hpp>
+#include <boost/fusion/iterator/equal_to.hpp>
+#include <boost/fusion/adapted/struct/define_struct_inline.hpp>
+#include <boost/mpl/assert.hpp>
+#include <boost/mpl/is_sequence.hpp>
+#include <boost/static_assert.hpp>
+#include <iostream>
+
+BOOST_FUSION_DEFINE_STRUCT_INLINE(empty_struct, )
+
+int
+main()
+{
+    using namespace boost;
+    using namespace boost::fusion;
+
+    std::cout << tuple_open('[');
+    std::cout << tuple_close(']');
+    std::cout << tuple_delimiter(", ");
+
+    {
+        BOOST_MPL_ASSERT_NOT((traits::is_view<empty_struct>));
+        empty_struct e;
+
+        std::cout << e << std::endl;
+        BOOST_TEST(e == make_vector());
+
+        BOOST_STATIC_ASSERT(fusion::result_of::size<empty_struct>::value == 0);
+        BOOST_STATIC_ASSERT(fusion::result_of::empty<empty_struct>::value);
+    }
+
+    {
+        vector<> v;
+        empty_struct e;
+        BOOST_TEST(v == e);
+        BOOST_TEST_NOT(v != e);
+        BOOST_TEST_NOT(v < e);
+        BOOST_TEST(v <= e);
+        BOOST_TEST_NOT(v > e);
+        BOOST_TEST(v >= e);
+    }
+
+    {
+        empty_struct e;
+
+        // conversion from empty_struct to vector
+        vector<> v(e);
+        v = e;
+
+        // conversion from empty_struct to list
+        //list<> l(e);
+        //l = e;
+    }
+
+    { // begin/end
+        typedef fusion::result_of::begin<empty_struct>::type b;
+        typedef fusion::result_of::end<empty_struct>::type e;
+
+        BOOST_MPL_ASSERT((fusion::result_of::equal_to<b, e>));
+    }
+
+    BOOST_MPL_ASSERT((mpl::is_sequence<empty_struct>));
+
+    return boost::report_errors();
+}