1// -*- C++ -*-
2//===-- lexicographical_compare.pass.cpp ----------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10// UNSUPPORTED: c++03, c++11, c++14
11
12#include "support/pstl_test_config.h"
13
14#include <iostream>
15#include <execution>
16#include <algorithm>
17
18#include "support/utils.h"
19
20using namespace TestUtils;
21
22struct test_one_policy
23{
24
25 template <typename ExecutionPolicy, typename Iterator1, typename Iterator2, typename Predicate>
26 void
27 operator()(ExecutionPolicy&& exec, Iterator1 begin1, Iterator1 end1, Iterator2 begin2, Iterator2 end2,
28 Predicate pred)
29 {
30 const bool expected = std::lexicographical_compare(begin1, end1, begin2, end2, pred);
31 const bool actual = std::lexicographical_compare(exec, begin1, end1, begin2, end2, pred);
32 EXPECT_TRUE(actual == expected, "wrong return result from lexicographical compare with predicate");
33 }
34
35 template <typename ExecutionPolicy, typename Iterator1, typename Iterator2>
36 void
37 operator()(ExecutionPolicy&& exec, Iterator1 begin1, Iterator1 end1, Iterator2 begin2, Iterator2 end2)
38 {
39 const bool expected = std::lexicographical_compare(begin1, end1, begin2, end2);
40 const bool actual = std::lexicographical_compare(exec, begin1, end1, begin2, end2);
41 EXPECT_TRUE(actual == expected, "wrong return result from lexicographical compare without predicate");
42 }
43};
44
45template <typename T1, typename T2, typename Predicate>
46void
47test(Predicate pred)
48{
49
50 const std::size_t max_n = 1000000;
51 Sequence<T1> in1(max_n, [](std::size_t k) { return T1(k); });
52 Sequence<T2> in2(2 * max_n, [](std::size_t k) { return T2(k); });
53
54 std::size_t n2;
55
56 // Test case: Call algorithm's version without predicate.
57 invoke_on_all_policies(test_one_policy(), in1.cbegin(), in1.cbegin() + max_n, in2.cbegin() + 3 * max_n / 10,
58 in2.cbegin() + 5 * max_n / 10);
59
60 // Test case: If one range is a prefix of another, the shorter range is lexicographically less than the other.
61 std::size_t max_n2 = max_n / 10;
62 invoke_on_all_policies(test_one_policy(), in1.begin(), in1.begin() + max_n, in2.cbegin(), in2.cbegin() + max_n2,
63 pred);
64 invoke_on_all_policies(test_one_policy(), in1.begin(), in1.begin() + max_n, in2.begin() + max_n2,
65 in2.begin() + 3 * max_n2, pred);
66
67 // Test case: If one range is a prefix of another, the shorter range is lexicographically less than the other.
68 max_n2 = 2 * max_n;
69 invoke_on_all_policies(test_one_policy(), in1.cbegin(), in1.cbegin() + max_n, in2.begin(), in2.begin() + max_n2,
70 pred);
71
72 for (std::size_t n1 = 0; n1 <= max_n; n1 = n1 <= 16 ? n1 + 1 : std::size_t(3.1415 * n1))
73 {
74 // Test case: If two ranges have equivalent elements and are of the same length, then the ranges are lexicographically equal.
75 n2 = n1;
76 invoke_on_all_policies(test_one_policy(), in1.begin(), in1.begin() + n1, in2.begin(), in2.begin() + n2, pred);
77
78 n2 = n1;
79 // Test case: two ranges have different elements and are of the same length (second sequence less than first)
80 std::size_t ind = n1 / 2;
81 in2[ind] = T2(-1);
82 invoke_on_all_policies(test_one_policy(), in1.begin(), in1.begin() + n1, in2.begin(), in2.begin() + n2, pred);
83 in2[ind] = T2(ind);
84
85 // Test case: two ranges have different elements and are of the same length (first sequence less than second)
86 ind = n1 / 5;
87 in1[ind] = T1(-1);
88 invoke_on_all_policies(test_one_policy(), in1.begin(), in1.begin() + n1, in2.cbegin(), in2.cbegin() + n2, pred);
89 in1[ind] = T1(ind);
90 }
91}
92
93template <typename Predicate>
94void
95test_string(Predicate pred)
96{
97
98 const std::size_t max_n = 1000000;
99 std::string in1 = "";
100 std::string in2 = "";
101 for (std::size_t n1 = 0; n1 <= max_n; ++n1)
102 {
103 in1 += n1;
104 }
105
106 for (std::size_t n1 = 0; n1 <= 2 * max_n; ++n1)
107 {
108 in2 += n1;
109 }
110
111 std::size_t n2;
112
113 for (std::size_t n1 = 0; n1 < in1.size(); n1 = n1 <= 16 ? n1 + 1 : std::size_t(3.1415 * n1))
114 {
115 // Test case: If two ranges have equivalent elements and are of the same length, then the ranges are lexicographically equal.
116 n2 = n1;
117 invoke_on_all_policies(test_one_policy(), in1.begin(), in1.begin() + n1, in2.begin(), in2.begin() + n2, pred);
118
119 n2 = n1;
120 // Test case: two ranges have different elements and are of the same length (second sequence less than first)
121 in2[n1 / 2] = 'a';
122 invoke_on_all_policies(test_one_policy(), in1.begin(), in1.begin() + n1, in2.begin(), in2.begin() + n2, pred);
123
124 // Test case: two ranges have different elements and are of the same length (first sequence less than second)
125 in1[n1 / 5] = 'a';
126 invoke_on_all_policies(test_one_policy(), in1.begin(), in1.begin() + n1, in2.cbegin(), in2.cbegin() + n2, pred);
127 }
128 invoke_on_all_policies(op: test_one_policy(), rest: in1.cbegin(), rest: in1.cbegin() + max_n, rest: in2.cbegin() + 3 * max_n / 10,
129 rest: in2.cbegin() + 5 * max_n / 10);
130}
131
132template <typename T>
133struct LocalWrapper
134{
135 explicit LocalWrapper(std::size_t k) : my_val(k) {}
136 bool
137 operator<(const LocalWrapper<T>& w) const
138 {
139 return my_val < w.my_val;
140 }
141
142 private:
143 T my_val;
144};
145
146template <typename T>
147struct test_non_const
148{
149 template <typename Policy, typename FirstIterator, typename SecondInterator>
150 void
151 operator()(Policy&& exec, FirstIterator first_iter, SecondInterator second_iter)
152 {
153 invoke_if(exec, [&]() {
154 lexicographical_compare(exec, first_iter, first_iter, second_iter, second_iter, non_const(std::less<T>()));
155 });
156 }
157};
158
159int
160main()
161{
162 test<uint16_t, float64_t>(pred: std::less<float64_t>());
163 test<float32_t, int32_t>(pred: std::greater<float32_t>());
164#if !defined(_PSTL_ICC_18_TEST_EARLY_EXIT_AVX_RELEASE_BROKEN)
165 test<float64_t, int32_t>(pred: [](const float64_t x, const int32_t y) { return x * x < y * y; });
166#endif
167 test<LocalWrapper<int32_t>, LocalWrapper<int32_t>>(
168 pred: [](const LocalWrapper<int32_t>& x, const LocalWrapper<int32_t>& y) { return x < y; });
169 test_string(pred: [](const char x, const char y) { return x < y; });
170
171 test_algo_basic_double<int32_t>(f: run_for_rnd_fw<test_non_const<int32_t>>());
172
173 std::cout << done() << std::endl;
174 return 0;
175}
176

source code of pstl/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare.pass.cpp