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 // UNSUPPORTED: libcpp-no-concepts 10 // UNSUPPORTED: libcpp-has-no-incomplete-ranges 11 12 // <string_view> 13 14 // template <class It, class End> 15 // constexpr basic_string_view(It begin, End end) 16 17 #include <string_view> 18 #include <cassert> 19 #include <iterator> 20 #include <ranges> 21 22 #include "make_string.h" 23 #include "test_iterators.h" 24 25 template<class CharT, class Sentinel> 26 constexpr void test() { 27 auto val = MAKE_STRING_VIEW(CharT, "test"); 28 auto sv = std::basic_string_view<CharT>(val.begin(), Sentinel(val.end())); 29 ASSERT_SAME_TYPE(decltype(sv), std::basic_string_view<CharT>); 30 assert(sv.size() == val.size()); 31 assert(sv.data() == val.data()); 32 } 33 34 constexpr bool test() { 35 test<char, char*>(); 36 #ifndef TEST_HAS_NO_WIDE_CHARACTERS 37 test<wchar_t, wchar_t*>(); 38 #endif 39 test<char8_t, char8_t*>(); 40 test<char16_t, char16_t*>(); 41 test<char32_t, char32_t*>(); 42 test<char, const char*>(); 43 test<char, sized_sentinel<const char*>>(); 44 return true; 45 } 46 47 #ifndef TEST_HAS_NO_EXCEPTIONS 48 template<class CharT> 49 struct ThrowingSentinel { 50 friend bool operator==(const CharT*, ThrowingSentinel) noexcept { return true; } 51 friend std::iter_difference_t<const CharT*> operator-(const CharT*, ThrowingSentinel) noexcept { return {}; } 52 friend std::iter_difference_t<const CharT*> operator-(ThrowingSentinel, const CharT*) { throw 42; } 53 }; 54 55 template <class CharT> 56 void test_throwing() { 57 auto val = MAKE_STRING_VIEW(CharT, "test"); 58 try { 59 (void)std::basic_string_view<CharT>(val.begin(), ThrowingSentinel<CharT>()); 60 assert(false); 61 } catch (int i) { 62 assert(i == 42); 63 } 64 } 65 66 void test_throwing() { 67 test_throwing<char>(); 68 #ifndef TEST_HAS_NO_WIDE_CHARACTERS 69 test_throwing<wchar_t>(); 70 #endif 71 test_throwing<char8_t>(); 72 test_throwing<char16_t>(); 73 test_throwing<char32_t>(); 74 } 75 #endif 76 77 static_assert( std::is_constructible_v<std::string_view, const char*, char*>); 78 static_assert( std::is_constructible_v<std::string_view, char*, const char*>); 79 static_assert(!std::is_constructible_v<std::string_view, char*, void*>); // not a sentinel 80 static_assert(!std::is_constructible_v<std::string_view, signed char*, signed char*>); // wrong char type 81 static_assert(!std::is_constructible_v<std::string_view, random_access_iterator<char*>, random_access_iterator<char*>>); // not contiguous 82 static_assert( std::is_constructible_v<std::string_view, contiguous_iterator<char*>, contiguous_iterator<char*>>); 83 84 int main(int, char**) { 85 test(); 86 static_assert(test()); 87 88 #ifndef TEST_HAS_NO_EXCEPTIONS 89 test_throwing(); 90 #endif 91 92 return 0; 93 } 94 95