libcxx/test/std/strings/string.view/string.view.template/starts_with.ptr.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: c++03, c++11, c++14, c++17
  10
  11 // <string_view>
  12
  13 //   constexpr bool starts_with(string_view x) const noexcept;
  14
  15 #include <string_view>
  16 #include <cassert>
  17
  18 #include "test_macros.h"
  19 #include "constexpr_char_traits.h"
  20
  21 int main(int, char**) {
  22   {
  23     typedef std::string_view SV;
  24     const char* s = "abcde";
  25     SV sv0{};
  26     SV sv1{s, 1};
  27     SV sv2{s, 2};
  28     SV svNot{"def", 3};
  29
  30     LIBCPP_ASSERT_NOEXCEPT(sv0.starts_with(""));
  31
  32     assert(sv0.starts_with(""));
  33     assert(!sv0.starts_with("a"));
  34
  35     assert(sv1.starts_with(""));
  36     assert(sv1.starts_with("a"));
  37     assert(!sv1.starts_with("ab"));
  38     assert(!sv1.starts_with("abc"));
  39     assert(!sv1.starts_with("abcd"));
  40     assert(!sv1.starts_with("abcde"));
  41     assert(!sv1.starts_with("def"));
  42
  43     assert(sv2.starts_with(s + 5));
  44     assert(sv2.starts_with("a"));
  45     assert(sv2.starts_with("ab"));
  46     assert(!sv2.starts_with("abc"));
  47     assert(!sv2.starts_with("abcd"));
  48     assert(!sv2.starts_with("abcde"));
  49     assert(!sv2.starts_with("def"));
  50
  51     assert(svNot.starts_with(""));
  52     assert(!svNot.starts_with("a"));
  53     assert(!svNot.starts_with("ab"));
  54     assert(!svNot.starts_with("abc"));
  55     assert(!svNot.starts_with("abcd"));
  56     assert(!svNot.starts_with("abcde"));
  57     assert(svNot.starts_with("def"));
  58   }
  59
  60 #if TEST_STD_VER > 11
  61   {
  62     typedef std::basic_string_view<char, constexpr_char_traits<char>> SV;
  63     constexpr const char* s = "abcde";
  64     constexpr SV sv0{};
  65     constexpr SV sv1{s, 1};
  66     constexpr SV sv2{s, 2};
  67     constexpr SV svNot{"def", 3};
  68
  69     static_assert(sv0.starts_with(""), "");
  70     static_assert(!sv0.starts_with("a"), "");
  71
  72     static_assert(sv1.starts_with(""), "");
  73     static_assert(sv1.starts_with("a"), "");
  74     static_assert(!sv1.starts_with("ab"), "");
  75     static_assert(!sv1.starts_with("abc"), "");
  76     static_assert(!sv1.starts_with("abcd"), "");
  77     static_assert(!sv1.starts_with("abcde"), "");
  78     static_assert(!sv1.starts_with("def"), "");
  79
  80     static_assert(sv2.starts_with(s + 5), "");
  81     static_assert(sv2.starts_with("a"), "");
  82     static_assert(sv2.starts_with("ab"), "");
  83     static_assert(!sv2.starts_with("abc"), "");
  84     static_assert(!sv2.starts_with("abcd"), "");
  85     static_assert(!sv2.starts_with("abcde"), "");
  86     static_assert(!sv2.starts_with("def"), "");
  87
  88     static_assert(svNot.starts_with(""), "");
  89     static_assert(!svNot.starts_with("a"), "");
  90     static_assert(!svNot.starts_with("ab"), "");
  91     static_assert(!svNot.starts_with("abc"), "");
  92     static_assert(!svNot.starts_with("abcd"), "");
  93     static_assert(!svNot.starts_with("abcde"), "");
  94     static_assert(svNot.starts_with("def"), "");
  95   }
  96 #endif
  97
  98   return 0;
  99 }