* testsuite/24_iterators/container_access.cc: New.

From-SVN: r226349

libstdc++-v3/testsuite/24_iterators/container_access.cc

+// { dg-do run }
+// { dg-options "-std=gnu++17" }
+
+// Copyright (C) 2015 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// 24.8, container access [iterator.container]
+
+#include <iterator>
+#include <vector>
+#include <testsuite_hooks.h>
+
+bool test __attribute__((unused)) = true;
+
+void
+test01()
+{
+  int i[42];
+  VERIFY(std::data(i) == i);
+  VERIFY(std::size(i) == 42);
+  VERIFY(!std::empty(i));
+}
+
+void
+test02()
+{
+  static constexpr int i[42]{};
+  constexpr auto d = std::data(i);
+  static_assert(d == i);
+  constexpr auto s = std::size(i);
+  static_assert(s == 42);
+  constexpr auto e = std::empty(i);
+  static_assert(!e);
+}
+
+int
+test03()
+{
+  std::initializer_list<int> il{1,2,3};
+  VERIFY(std::data(il) == il.begin());
+  VERIFY(std::size(il) == 3);
+  VERIFY(!std::empty(il));
+  std::initializer_list<int> il2{};
+  VERIFY(std::size(il2) == 0);
+  VERIFY(std::empty(il2));
+  constexpr std::initializer_list<int> il3{1,2,3};
+  constexpr auto d = std::data(il3);
+  static_assert(d == il3.begin());
+  constexpr auto s = std::size(il3);
+  static_assert(s == 3);
+  constexpr auto e = std::empty(il3);
+  static_assert(!e);
+
+}
+
+int
+test04()
+{
+  std::vector<int> v{1,2,3};
+  VERIFY(std::data(v) == v.data());
+  VERIFY(std::size(v) == v.size());
+  VERIFY(!std::empty(v));
+  std::vector<int> v2{};
+  VERIFY(std::size(v2) == v2.size());
+  VERIFY(std::empty(v2));
+}
+
+int
+main()
+{
+  test01();
+  test02();
+  test03();
+  test04();
+}