libcxx/test/std/strings/string.view/string.view.modifiers/remove_suffix.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 // void remove_suffix(size_type _n)
  14
  15 #include <cassert>
  16 #include <cstddef>
  17 #include <string_view>
  18
  19 #include "test_macros.h"
  20
  21 template <typename CharT>
  22 void test(const CharT* s, std::size_t len) {
  23   typedef std::basic_string_view<CharT> SV;
  24   {
  25     SV sv1(s);
  26     assert(sv1.size() == len);
  27     assert(sv1.data() == s);
  28
  29     if (len > 0) {
  30       sv1.remove_suffix(1);
  31       assert(sv1.size() == (len - 1));
  32       assert(sv1.data() == s);
  33       sv1.remove_suffix(len - 1);
  34     }
  35
  36     assert(sv1.size() == 0);
  37     sv1.remove_suffix(0);
  38     assert(sv1.size() == 0);
  39   }
  40 }
  41
  42 #if TEST_STD_VER > 11
  43 constexpr std::size_t test_ce(size_t n, size_t k) {
  44   typedef std::basic_string_view<char> SV;
  45   SV sv1{"ABCDEFGHIJKL", n};
  46   sv1.remove_suffix(k);
  47   return sv1.size();
  48 }
  49 #endif
  50
  51 int main(int, char**) {
  52   test("ABCDE", 5);
  53   test("a", 1);
  54   test("", 0);
  55
  56 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
  57   test(L"ABCDE", 5);
  58   test(L"a", 1);
  59   test(L"", 0);
  60 #endif
  61
  62 #if TEST_STD_VER >= 11
  63   test(u"ABCDE", 5);
  64   test(u"a", 1);
  65   test(u"", 0);
  66
  67   test(U"ABCDE", 5);
  68   test(U"a", 1);
  69   test(U"", 0);
  70 #endif
  71
  72 #if TEST_STD_VER > 11
  73   {
  74     static_assert(test_ce(5, 0) == 5, "");
  75     static_assert(test_ce(5, 1) == 4, "");
  76     static_assert(test_ce(5, 5) == 0, "");
  77     static_assert(test_ce(9, 3) == 6, "");
  78   }
  79 #endif
  80
  81   return 0;
  82 }