libcxx/test/std/strings/basic.string/string.starts_with/starts_with.char.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 // UNSUPPORTED: c++03, c++11, c++14, c++17
   9
  10 // <string>
  11
  12 // constexpr bool starts_with(charT x) const noexcept;
  13
  14 #include <string>
  15 #include <cassert>
  16
  17 #include "test_macros.h"
  18
  19 template <class S>
  20 constexpr void test_string() {
  21   S s1{};
  22   S s2{"abcde", 5};
  23
  24   ASSERT_NOEXCEPT(s1.starts_with('e'));
  25
  26   assert(!s1.starts_with('a'));
  27   assert(!s1.starts_with('x'));
  28   assert(s2.starts_with('a'));
  29   assert(!s2.starts_with('x'));
  30 }
  31
  32 constexpr bool test() {
  33   test_string<std::string>();
  34
  35   return true;
  36 }
  37
  38 int main(int, char**) {
  39   test();
  40   static_assert(test());
  41
  42   return 0;
  43 }