xref: /llvm-project/libcxx/test/std/strings/basic.string/string.modifiers/string_append/push_back.pass.cpp (revision 5dfdac74cadd9483a66eb17e51dc632b554cccb1)
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 // <string>
10 
11 // void push_back(charT c) // constexpr since C++20
12 
13 #include <string>
14 #include <algorithm>
15 #include <cassert>
16 
17 #include "test_macros.h"
18 #include "min_allocator.h"
19 #include "asan_testing.h"
20 
21 struct VeryLarge {
22   long long a;
23   char b;
24 };
25 
26 template <>
27 struct std::char_traits<VeryLarge> {
28   using char_type  = VeryLarge;
29   using int_type   = int;
30   using off_type   = streamoff;
31   using pos_type   = streampos;
32   using state_type = mbstate_t;
33 
34   static TEST_CONSTEXPR_CXX20 void assign(char_type& c1, const char_type& c2) { c1 = c2; }
35   static bool eq(char_type c1, char_type c2);
36   static bool lt(char_type c1, char_type c2);
37 
38   static int compare(const char_type* s1, const char_type* s2, std::size_t n);
39   static std::size_t length(const char_type* s);
40   static const char_type* find(const char_type* s, std::size_t n, const char_type& a);
41   static char_type* move(char_type* s1, const char_type* s2, std::size_t n);
42   static TEST_CONSTEXPR_CXX20 char_type* copy(char_type* s1, const char_type* s2, std::size_t n) {
43     std::copy_n(s2, n, s1);
44     return s1;
45   }
46   static TEST_CONSTEXPR_CXX20 char_type* assign(char_type* s, std::size_t n, char_type a) {
47     std::fill_n(s, n, a);
48     return s;
49   }
50 
51   static int_type not_eof(int_type c);
52   static char_type to_char_type(int_type c);
53   static int_type to_int_type(char_type c);
54   static bool eq_int_type(int_type c1, int_type c2);
55   static int_type eof();
56 };
57 
58 template <class S>
59 TEST_CONSTEXPR_CXX20 void test(S s, typename S::value_type c, S expected) {
60   s.push_back(c);
61   LIBCPP_ASSERT(s.__invariants());
62   assert(s == expected);
63   LIBCPP_ASSERT(is_string_asan_correct(s));
64 }
65 
66 template <class S>
67 TEST_CONSTEXPR_CXX20 void test_string() {
68   test(S(), 'a', S(1, 'a'));
69   test(S("12345"), 'a', S("12345a"));
70   test(S("12345678901234567890"), 'a', S("12345678901234567890a"));
71   test(S("123abcabcdefghabcdefgh"), 'a', S("123abcabcdefghabcdefgha"));
72   test(S("123abcabcdefghabcdefgha"), 'b', S("123abcabcdefghabcdefghab"));
73   test(S("123abcabcdefghabcdefghab"), 'c', S("123abcabcdefghabcdefghabc"));
74   test(S("123abcabcdefghabcdefghabc"), 'd', S("123abcabcdefghabcdefghabcd"));
75 }
76 
77 TEST_CONSTEXPR_CXX20 bool test() {
78   test_string<std::string>();
79 #if TEST_STD_VER >= 11
80   test_string<std::basic_string<char, std::char_traits<char>, min_allocator<char> > >();
81   test_string<std::basic_string<char, std::char_traits<char>, safe_allocator<char> > >();
82 #endif
83   {
84     // https://llvm.org/PR31454
85     std::basic_string<VeryLarge> s;
86     VeryLarge vl = {};
87     s.push_back(vl);
88     s.push_back(vl);
89     s.push_back(vl);
90   }
91 
92   return true;
93 }
94 
95 int main(int, char**) {
96   test();
97 #if TEST_STD_VER > 17
98   static_assert(test());
99 #endif
100 
101   return 0;
102 }
103