Implement std::string_view as described in http://wg21.link/P0254R1. Reviewed as https://reviews.llvm.org/D21459

llvm-svn: 276238

1 files changed, 55 insertions, 0 deletions

diff --git a/libcxx/test/std/strings/string.view/string.view.hash/string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.hash/string_view.pass.cpp
new file mode 100644
index 00000000000..a3a8a72566d
--- /dev/null
+++ b/libcxx/test/std/strings/string.view/string.view.hash/string_view.pass.cpp
@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <functional>
+
+// template <class T>
+// struct hash
+//     : public unary_function<T, size_t>
+// {
+//     size_t operator()(T val) const;
+// };
+
+// Not very portable
+
+#include <string_view>
+#include <cassert>
+#include <type_traits>
+
+using std::string_view;
+
+template <class T>
+void
+test()
+{
+    typedef std::hash<T> H;
+    static_assert((std::is_same<typename H::argument_type, T>::value), "" );
+    static_assert((std::is_same<typename H::result_type, std::size_t>::value), "" );
+    H h;
+//     std::string g1 = "1234567890";
+//     std::string g2 = "1234567891";
+    typedef typename T::value_type char_type;
+    char_type g1 [ 10 ];
+    char_type g2 [ 10 ];
+    for ( int i = 0; i < 10; ++i )
+        g1[i] = g2[9-i] = '0' + i;
+    T s1(g1, 10);
+    T s2(g2, 10);
+    assert(h(s1) != h(s2));
+}
+
+int main()
+{
+    test<std::string_view>();
+#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
+    test<std::u16string_view>();
+    test<std::u32string_view>();
+#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+    test<std::wstring_view>();
+}