libcxx/test/std/strings/string.view/string.view.cons/from_literal.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // UNSUPPORTED: !stdlib=libc++ && (c++03 || c++11 || c++14)
  10
  11 // <string_view>
  12
  13 // constexpr basic_string_view(const _CharT* _s)
  14 //    : __data (_s), __size(_Traits::length(_s)) {}
  15
  16 #include <string_view>
  17 #include <string>
  18 #include <cassert>
  19
  20 #include "test_macros.h"
  21 #include "constexpr_char_traits.h"
  22
  23 template <typename CharT>
  24 size_t StrLen(const CharT* s) {
  25   std::size_t retVal = 0;
  26   while (*s != 0) {
  27     ++retVal;
  28     ++s;
  29   }
  30   return retVal;
  31 }
  32
  33 template <typename CharT>
  34 void test(const CharT* s) {
  35   typedef std::basic_string_view<CharT> SV;
  36   //  I'd love to do this, but it would require traits::length() to be noexcept
  37   //  LIBCPP_ASSERT_NOEXCEPT(SV(s));
  38
  39   SV sv1(s);
  40   assert(sv1.size() == StrLen(s));
  41   assert(sv1.data() == s);
  42 }
  43
  44 int main(int, char**) {
  45   test("QBCDE");
  46   test("A");
  47   test("");
  48
  49 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
  50   test(L"QBCDE");
  51   test(L"A");
  52   test(L"");
  53 #endif
  54
  55 #if TEST_STD_VER >= 11
  56   test(u"QBCDE");
  57   test(u"A");
  58   test(u"");
  59
  60   test(U"QBCDE");
  61   test(U"A");
  62   test(U"");
  63 #endif
  64
  65 #if TEST_STD_VER > 11
  66   {
  67     constexpr std::basic_string_view<char, constexpr_char_traits<char>> sv1("ABCDE");
  68     static_assert(sv1.size() == 5, "");
  69   }
  70 #endif
  71
  72   return 0;
  73 }