Add test/variant_value_construct(_cx)

2017-05-30 16:05:55 +03:00
parent 5aa16c5bf7
commit a99b5f8e2e
3 changed files with 235 additions and 0 deletions
@@ -0,0 +1,109 @@
+
+// Copyright 2017 Peter Dimov.
+//
+// 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/variant2/variant.hpp>
+
+using namespace boost::variant2;
+
+struct X
+{
+    constexpr operator int() const { return 2; }
+};
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+int main()
+{
+    {
+        constexpr variant<int> v( 1 );
+
+        STATIC_ASSERT( v.index() == 0 );
+        STATIC_ASSERT( get<0>(v) == 1 );
+    }
+
+    {
+        constexpr variant<int> v( 'a' );
+
+        STATIC_ASSERT( v.index() == 0 );
+        STATIC_ASSERT( get<0>(v) == 'a' );
+    }
+
+    {
+        constexpr variant<int> v( X{} );
+
+        STATIC_ASSERT( v.index() == 0 );
+        STATIC_ASSERT( get<0>(v) == 2 );
+    }
+
+    {
+        constexpr variant<int const> v( 1 );
+
+        STATIC_ASSERT( v.index() == 0 );
+        STATIC_ASSERT( get<0>(v) == 1 );
+    }
+
+    {
+        constexpr variant<int const> v( 'a' );
+
+        STATIC_ASSERT( v.index() == 0 );
+        STATIC_ASSERT( get<0>(v) == 'a' );
+    }
+
+    {
+        constexpr variant<int const> v( X{} );
+
+        STATIC_ASSERT( v.index() == 0 );
+        STATIC_ASSERT( get<0>(v) == 2 );
+    }
+
+    {
+        constexpr variant<int, float, X> v( 1 );
+
+        STATIC_ASSERT( v.index() == 0 );
+        STATIC_ASSERT( holds_alternative<int>(v) );
+        STATIC_ASSERT( get<0>(v) == 1 );
+    }
+
+    {
+        constexpr variant<int, float, X> v( 'a' );
+
+        STATIC_ASSERT( v.index() == 0 );
+        STATIC_ASSERT( holds_alternative<int>(v) );
+        STATIC_ASSERT( get<0>(v) == 'a' );
+    }
+
+    {
+        constexpr variant<int, float, X> v( 3.14f );
+
+        STATIC_ASSERT( v.index() == 1 );
+        STATIC_ASSERT( holds_alternative<float>(v) );
+        STATIC_ASSERT( get<1>(v) == 3.14f );
+    }
+
+    {
+        constexpr variant<int, float, X> v( X{} );
+
+        STATIC_ASSERT( v.index() == 2 );
+        STATIC_ASSERT( holds_alternative<X>(v) );
+    }
+
+    {
+        constexpr variant<int, int, float, X> v( 3.14f );
+
+        STATIC_ASSERT( v.index() == 2 );
+        STATIC_ASSERT( holds_alternative<float>(v) );
+        STATIC_ASSERT( get<2>(v) == 3.14f );
+    }
+
+    {
+        constexpr variant<int, int, float, X> v( X{} );
+
+        STATIC_ASSERT( v.index() == 3 );
+        STATIC_ASSERT( holds_alternative<X>(v) );
+    }
+}