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 // UNSUPPORTED: c++03, c++11, c++14, c++17
10 // UNSUPPORTED: libcpp-has-no-incomplete-ranges
11 
12 // constexpr W operator*() const noexcept(is_nothrow_copy_constructible_v<W>);
13 
14 #include "test_macros.h"
15 
16 TEST_CLANG_DIAGNOSTIC_IGNORED("-Wsign-compare")
17 TEST_GCC_DIAGNOSTIC_IGNORED("-Wsign-compare")
18 TEST_MSVC_DIAGNOSTIC_IGNORED(4018) // various "signed/unsigned mismatch"
19 
20 #include <ranges>
21 #include <cassert>
22 
23 #include "../types.h"
24 
25 struct NotNoexceptCopy {
26   using difference_type = int;
27 
28   int value_;
29   constexpr explicit NotNoexceptCopy(int value = 0) : value_(value) {}
30   NotNoexceptCopy(const NotNoexceptCopy&) noexcept(false) = default;
31 
32   bool operator==(const NotNoexceptCopy&) const = default;
33 
34   friend constexpr NotNoexceptCopy& operator+=(NotNoexceptCopy &lhs, const NotNoexceptCopy& rhs) {
35     lhs.value_ += rhs.value_; return lhs;
36   }
37   friend constexpr NotNoexceptCopy& operator-=(NotNoexceptCopy &lhs, const NotNoexceptCopy& rhs) {
38     lhs.value_ -= rhs.value_; return lhs;
39   }
40 
41   friend constexpr NotNoexceptCopy operator+(NotNoexceptCopy lhs, NotNoexceptCopy rhs) {
42     return NotNoexceptCopy{lhs.value_ + rhs.value_};
43   }
44   friend constexpr int operator-(NotNoexceptCopy lhs, NotNoexceptCopy rhs) {
45     return lhs.value_ - rhs.value_;
46   }
47 
48   constexpr NotNoexceptCopy& operator++()     { ++value_; return *this; }
49   constexpr void              operator++(int) { ++value_;               }
50 };
51 
52 template<class T>
53 constexpr void testType() {
54   {
55     std::ranges::iota_view<T> io(T(0));
56     auto iter = io.begin();
57     for (int i = 0; i < 100; ++i, ++iter)
58       assert(*iter == T(i));
59 
60     static_assert(noexcept(*iter) == !std::same_as<T, NotNoexceptCopy>);
61   }
62   {
63     std::ranges::iota_view<T> io(T(10));
64     auto iter = io.begin();
65     for (int i = 10; i < 100; ++i, ++iter)
66       assert(*iter == T(i));
67   }
68   {
69     const std::ranges::iota_view<T> io(T(0));
70     auto iter = io.begin();
71     for (int i = 0; i < 100; ++i, ++iter)
72       assert(*iter == T(i));
73   }
74   {
75     const std::ranges::iota_view<T> io(T(10));
76     auto iter = io.begin();
77     for (int i = 10; i < 100; ++i, ++iter)
78       assert(*iter == T(i));
79   }
80 }
81 
82 constexpr bool test() {
83   testType<SomeInt>();
84   testType<NotNoexceptCopy>();
85   testType<signed long>();
86   testType<unsigned long>();
87   testType<int>();
88   testType<unsigned>();
89   testType<short>();
90   testType<unsigned short>();
91 
92   // Tests a mix of signed unsigned types.
93   {
94     const std::ranges::iota_view<int, unsigned> io(0, 10);
95     auto iter = io.begin();
96     for (int i = 0; i < 10; ++i, ++iter)
97       assert(*iter == i);
98   }
99 
100   return true;
101 }
102 
103 int main(int, char**) {
104   test();
105   static_assert(test());
106 
107   return 0;
108 }
109