1 files changed, 73 insertions, 0 deletions
diff --git a/src/boost/libs/hana/test/type/metafunction_class.cpp b/src/boost/libs/hana/test/type/metafunction_class.cpp
new file mode 100644
index 000000000..b0123708b
--- /dev/null
+++ b/src/boost/libs/hana/test/type/metafunction_class.cpp
@@ -0,0 +1,73 @@
+// Copyright Louis Dionne 2013-2017
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+
+#include <boost/hana/assert.hpp>
+#include <boost/hana/concept/metafunction.hpp>
+#include <boost/hana/equal.hpp>
+#include <boost/hana/not.hpp>
+#include <boost/hana/type.hpp>
+
+#include <type_traits>
+namespace hana = boost::hana;
+
+
+struct x1; struct x2; struct x3;
+struct y1 { }; struct y2 { }; struct y3 { };
+struct f { template <typename ...> struct apply { struct type; }; };
+
+template <typename F, typename ...T>
+constexpr auto valid_call(F f, T ...t) -> decltype(((void)f(t...)), true)
+{ return true; }
+constexpr auto valid_call(...)
+{ return false; }
+
+BOOST_HANA_CONSTANT_CHECK(hana::equal(
+    hana::metafunction_class<f>(),
+    hana::type_c<f::apply<>::type>
+));
+BOOST_HANA_CONSTANT_CHECK(hana::equal(
+    hana::metafunction_class<f>(hana::type_c<x1>),
+    hana::type_c<f::apply<x1>::type>
+));
+BOOST_HANA_CONSTANT_CHECK(hana::equal(
+    hana::metafunction_class<f>(hana::type_c<x1>, hana::type_c<x2>),
+    hana::type_c<f::apply<x1, x2>::type>
+));
+BOOST_HANA_CONSTANT_CHECK(hana::equal(
+    hana::metafunction_class<f>(hana::type_c<x1>, hana::type_c<x2>, hana::type_c<x3>),
+    hana::type_c<f::apply<x1, x2, x3>::type>
+));
+
+using F = decltype(hana::metafunction_class<f>);
+static_assert(std::is_same<F::apply<>, f::apply<>>{}, "");
+static_assert(std::is_same<F::apply<x1>, f::apply<x1>>{}, "");
+static_assert(std::is_same<F::apply<x1, x2>, f::apply<x1, x2>>{}, "");
+static_assert(std::is_same<F::apply<x1, x2, x3>, f::apply<x1, x2, x3>>{}, "");
+
+// Make sure we're SFINAE-friendly
+struct no_type { template <typename ...> struct apply { }; };
+static_assert(!valid_call(hana::metafunction_class<no_type>), "");
+static_assert(!valid_call(hana::metafunction_class<no_type>, hana::type_c<x1>), "");
+
+// Make sure we model the Metafunction concept
+static_assert(hana::Metafunction<decltype(hana::metafunction_class<f>)>::value, "");
+static_assert(hana::Metafunction<decltype(hana::metafunction_class<f>)&>::value, "");
+
+// Make sure metafunction_class is SFINAE-friendly
+struct not_a_mfc1 { template <typename ...> struct apply { }; };
+struct not_a_mfc2 { };
+BOOST_HANA_CONSTANT_CHECK(hana::not_(
+    hana::is_valid(hana::metafunction_class<not_a_mfc1>)(hana::type_c<void>)
+));
+BOOST_HANA_CONSTANT_CHECK(hana::not_(
+    hana::is_valid(hana::metafunction_class<not_a_mfc2>)(hana::type_c<void>)
+));
+
+
+// Make sure we don't read from a non-constexpr variable
+int main() {
+    auto t = hana::type_c<x1>;
+    constexpr auto r = hana::metafunction_class<f>(t);
+    (void)r;
+}