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// <vector>
10// vector<bool>
11
12// void shrink_to_fit();
13
14// XFAIL: FROZEN-CXX03-HEADERS-FIXME
15
16#include <cassert>
17#include <climits>
18#include <vector>
19
20#include "increasing_allocator.h"
21#include "min_allocator.h"
22#include "test_macros.h"
23
24TEST_CONSTEXPR_CXX20 bool tests() {
25 {
26 using C = std::vector<bool>;
27 C v(100);
28 v.push_back(x: 1);
29 C::size_type before_cap = v.capacity();
30 v.clear();
31 v.shrink_to_fit();
32 assert(v.capacity() <= before_cap);
33 LIBCPP_ASSERT(v.capacity() == 0); // libc++ honors the shrink_to_fit request as a QOI matter
34 assert(v.size() == 0);
35 }
36 {
37 using C = std::vector<bool, min_allocator<bool> >;
38 C v(100);
39 v.push_back(1);
40 C::size_type before_cap = v.capacity();
41 v.shrink_to_fit();
42 assert(v.capacity() >= 101);
43 assert(v.capacity() <= before_cap);
44 assert(v.size() == 101);
45 v.erase(v.begin() + 1, v.end());
46 v.shrink_to_fit();
47 assert(v.capacity() <= before_cap);
48 LIBCPP_ASSERT(v.capacity() == C(1).capacity()); // libc++ honors the shrink_to_fit request as a QOI matter.
49 assert(v.size() == 1);
50 }
51
52#if defined(_LIBCPP_VERSION)
53 {
54 using C = std::vector<bool>;
55 unsigned bits_per_word = static_cast<unsigned>(sizeof(C::__storage_type) * CHAR_BIT);
56 C v(bits_per_word);
57 v.push_back(1);
58 assert(v.capacity() == bits_per_word * 2);
59 assert(v.size() == bits_per_word + 1);
60 v.pop_back();
61 v.shrink_to_fit();
62 assert(v.capacity() == bits_per_word);
63 assert(v.size() == bits_per_word);
64 }
65 {
66 using C = std::vector<bool>;
67 unsigned bits_per_word = static_cast<unsigned>(sizeof(C::__storage_type) * CHAR_BIT);
68 C v;
69 v.reserve(bits_per_word * 2);
70 v.push_back(1);
71 assert(v.capacity() == bits_per_word * 2);
72 assert(v.size() == 1);
73 v.shrink_to_fit();
74 assert(v.capacity() == bits_per_word);
75 assert(v.size() == 1);
76 }
77#endif
78
79 return true;
80}
81
82#if TEST_STD_VER >= 23
83// https://github.com/llvm/llvm-project/issues/95161
84constexpr bool test_increasing_allocator() {
85 std::vector<bool, increasing_allocator<bool>> v;
86 v.push_back(1);
87 std::size_t capacity = v.capacity();
88 v.shrink_to_fit();
89 assert(v.capacity() <= capacity);
90 assert(v.size() == 1);
91
92 return true;
93}
94#endif // TEST_STD_VER >= 23
95
96int main(int, char**) {
97 tests();
98#if TEST_STD_VER > 17
99 static_assert(tests());
100#endif
101#if TEST_STD_VER >= 23
102 test_increasing_allocator();
103 static_assert(test_increasing_allocator());
104#endif // TEST_STD_VER >= 23
105
106 return 0;
107}
108

source code of libcxx/test/std/containers/sequences/vector.bool/shrink_to_fit.pass.cpp