Implement string_view from the library fundamentals TS (n4023). Also works in C++11 and 03, with reduced functionality (mostly in the area of constexpr)

llvm-svn: 210659

libcxx/test/experimental/string.view/string.view.comparison/opeq.string_view.string.pass.cpp

@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <string>
+
+// template<class charT, class traits, class Allocator>
+//   bool operator==(const charT* lhs, const basic_string<charT,traits> rhs);
+// template<class charT, class traits, class Allocator>
+//   bool operator==(const basic_string_view<charT,traits> lhs, const CharT* rhs);
+
+#include <experimental/string_view>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+template <class S>
+void
+test(const std::string &lhs, S rhs, bool x)
+{
+    assert((lhs == rhs) == x);
+    assert((rhs == lhs) == x);
+}
+
+int main()
+{
+    {
+    typedef std::experimental::string_view S;
+    test("", S(""), true);
+    test("", S("abcde"), false);
+    test("", S("abcdefghij"), false);
+    test("", S("abcdefghijklmnopqrst"), false);
+    test("abcde", S(""), false);
+    test("abcde", S("abcde"), true);
+    test("abcde", S("abcdefghij"), false);
+    test("abcde", S("abcdefghijklmnopqrst"), false);
+    test("abcdefghij", S(""), false);
+    test("abcdefghij", S("abcde"), false);
+    test("abcdefghij", S("abcdefghij"), true);
+    test("abcdefghij", S("abcdefghijklmnopqrst"), false);
+    test("abcdefghijklmnopqrst", S(""), false);
+    test("abcdefghijklmnopqrst", S("abcde"), false);
+    test("abcdefghijklmnopqrst", S("abcdefghij"), false);
+    test("abcdefghijklmnopqrst", S("abcdefghijklmnopqrst"), true);
+    }
+}
+#else
+int main () {}
+#endif