From 01493e4acbe1417cdc9bb361f450916bc00c94cc Mon Sep 17 00:00:00 2001
From: Peter Dimov <pdimov@pdimov.com>
Date: Mon, 8 Jun 2015 01:34:06 +0300
Subject: [PATCH] Add a few more common_type tests.

---
 test/common_type_3_test.cpp | 22 ++++++++++++++
 test/common_type_4_test.cpp | 57 +++++++++++++++++++++++++++++++++++++
 test/common_type_5_test.cpp | 56 ++++++++++++++++++++++++++++++++++++
 3 files changed, 135 insertions(+)
 create mode 100644 test/common_type_3_test.cpp
 create mode 100644 test/common_type_4_test.cpp
 create mode 100644 test/common_type_5_test.cpp

diff --git a/test/common_type_3_test.cpp b/test/common_type_3_test.cpp
new file mode 100644
index 0000000..fd228b8
--- /dev/null
+++ b/test/common_type_3_test.cpp
@@ -0,0 +1,22 @@
+
+//  Copyright Peter Dimov 2015
+//  Use, modification and distribution are subject to the 
+//  Boost Software License, Version 1.0. (See accompanying file 
+//  LICENSE_1_0.txt or copy at http://www.tt.org/LICENSE_1_0.txt)
+
+#include "test.hpp"
+#include "check_type.hpp"
+#ifdef TEST_STD
+#  include <type_traits>
+#else
+#  include <boost/type_traits/common_type.hpp>
+#endif
+#include <iostream>
+
+TT_TEST_BEGIN(common_type_3)
+{
+    // just check whether the nullary specialization compiles
+    tt::common_type<> tmp;
+    (void)tmp;
+}
+TT_TEST_END
diff --git a/test/common_type_4_test.cpp b/test/common_type_4_test.cpp
new file mode 100644
index 0000000..3a6659f
--- /dev/null
+++ b/test/common_type_4_test.cpp
@@ -0,0 +1,57 @@
+
+//  Copyright Peter Dimov 2015
+//  Use, modification and distribution are subject to the 
+//  Boost Software License, Version 1.0. (See accompanying file 
+//  LICENSE_1_0.txt or copy at http://www.tt.org/LICENSE_1_0.txt)
+
+#include "test.hpp"
+#include "check_type.hpp"
+#ifdef TEST_STD
+#  include <type_traits>
+#else
+#  include <boost/type_traits/common_type.hpp>
+#endif
+#include <iostream>
+
+TT_TEST_BEGIN(common_type_4)
+{
+    // the unary case should be the same as decay
+
+    BOOST_CHECK_TYPE(tt::common_type<void>::type, void);
+    BOOST_CHECK_TYPE(tt::common_type<void const>::type, void);
+    BOOST_CHECK_TYPE(tt::common_type<void volatile>::type, void);
+    BOOST_CHECK_TYPE(tt::common_type<void const volatile>::type, void);
+
+    BOOST_CHECK_TYPE(tt::common_type<char>::type, char);
+    BOOST_CHECK_TYPE(tt::common_type<char const>::type, char);
+    BOOST_CHECK_TYPE(tt::common_type<char volatile>::type, char);
+    BOOST_CHECK_TYPE(tt::common_type<char const volatile>::type, char);
+
+    BOOST_CHECK_TYPE(tt::common_type<char&>::type, char);
+    BOOST_CHECK_TYPE(tt::common_type<char const&>::type, char);
+    BOOST_CHECK_TYPE(tt::common_type<char volatile&>::type, char);
+    BOOST_CHECK_TYPE(tt::common_type<char const volatile&>::type, char);
+
+    BOOST_CHECK_TYPE(tt::common_type<char[]>::type, char*);
+    BOOST_CHECK_TYPE(tt::common_type<char const[]>::type, char const*);
+    BOOST_CHECK_TYPE(tt::common_type<char volatile[]>::type, char volatile*);
+    BOOST_CHECK_TYPE(tt::common_type<char const volatile[]>::type, char const volatile*);
+
+    BOOST_CHECK_TYPE(tt::common_type<char[2]>::type, char*);
+    BOOST_CHECK_TYPE(tt::common_type<char const[2]>::type, char const*);
+    BOOST_CHECK_TYPE(tt::common_type<char volatile[2]>::type, char volatile*);
+    BOOST_CHECK_TYPE(tt::common_type<char const volatile[2]>::type, char const volatile*);
+
+    BOOST_CHECK_TYPE(tt::common_type<char (&) [2]>::type, char*);
+    BOOST_CHECK_TYPE(tt::common_type<char const (&) [2]>::type, char const*);
+    BOOST_CHECK_TYPE(tt::common_type<char volatile (&) [2]>::type, char volatile*);
+    BOOST_CHECK_TYPE(tt::common_type<char const volatile (&) [2]>::type, char const volatile*);
+
+    BOOST_CHECK_TYPE(tt::common_type<char()>::type, char(*)());
+
+    BOOST_CHECK_TYPE(tt::common_type<UDT()>::type, UDT(*)());
+    BOOST_CHECK_TYPE(tt::common_type<UDT const()>::type, UDT const(*)());
+    BOOST_CHECK_TYPE(tt::common_type<UDT volatile()>::type, UDT volatile(*)());
+    BOOST_CHECK_TYPE(tt::common_type<UDT const volatile()>::type, UDT const volatile(*)());
+}
+TT_TEST_END
diff --git a/test/common_type_5_test.cpp b/test/common_type_5_test.cpp
new file mode 100644
index 0000000..0a0e237
--- /dev/null
+++ b/test/common_type_5_test.cpp
@@ -0,0 +1,56 @@
+
+//  Copyright Peter Dimov 2015
+//  Use, modification and distribution are subject to the 
+//  Boost Software License, Version 1.0. (See accompanying file 
+//  LICENSE_1_0.txt or copy at http://www.tt.org/LICENSE_1_0.txt)
+
+#include "test.hpp"
+#include "check_type.hpp"
+#ifdef TEST_STD
+#  include <type_traits>
+#else
+#  include <boost/type_traits/common_type.hpp>
+#endif
+#include <iostream>
+
+template<class T> struct X
+{
+    T t_;
+
+    X(): t_() {}
+    template<class U> X( X<U> const & x ): t_( x.t_ ) {}
+};
+
+namespace boost
+{
+
+    template<class T, class U> struct common_type< X<T>, X<U> >
+    {
+        typedef X<typename common_type<T, U>::type> type;
+    };
+
+} // namespace boost
+
+TT_TEST_BEGIN(common_type_5)
+{
+    // user specializations, binary
+
+    BOOST_CHECK_TYPE3( tt::common_type< X<char>, X<char> >::type, X<char> );
+
+    BOOST_CHECK_TYPE3( tt::common_type< X<char>&, X<char>& >::type, X<char> );
+    BOOST_CHECK_TYPE3( tt::common_type< X<char>&, X<char> const& >::type, X<char> );
+    BOOST_CHECK_TYPE3( tt::common_type< X<char> const&, X<char>& >::type, X<char> );
+    BOOST_CHECK_TYPE3( tt::common_type< X<char> const&, X<char> const& >::type, X<char> );
+
+    BOOST_CHECK_TYPE3( tt::common_type< X<char>, X<unsigned char> >::type, X<int> );
+
+    BOOST_CHECK_TYPE3( tt::common_type< X<char>&, X<unsigned char>& >::type, X<int> );
+    BOOST_CHECK_TYPE3( tt::common_type< X<char>&, X<unsigned char> const& >::type, X<int> );
+    BOOST_CHECK_TYPE3( tt::common_type< X<char> const&, X<unsigned char>& >::type, X<int> );
+    BOOST_CHECK_TYPE3( tt::common_type< X<char> const&, X<unsigned char> const& >::type, X<int> );
+
+    // ternary
+
+    BOOST_CHECK_TYPE4( tt::common_type< X<char>&, X<long> const&, X<short> volatile& >::type, X<long> );
+}
+TT_TEST_END