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 // std::ranges::ssize
13
14 #include <ranges>
15
16 #include <cassert>
17 #include "test_macros.h"
18 #include "test_iterators.h"
19
20 using RangeSSizeT = decltype(std::ranges::ssize);
21
22 static_assert(!std::is_invocable_v<RangeSSizeT, int[]>);
23 static_assert( std::is_invocable_v<RangeSSizeT, int[1]>);
24 static_assert( std::is_invocable_v<RangeSSizeT, int (&&)[1]>);
25 static_assert( std::is_invocable_v<RangeSSizeT, int (&)[1]>);
26
27 struct SizeMember {
sizeSizeMember28 constexpr size_t size() { return 42; }
29 };
30 static_assert(!std::is_invocable_v<decltype(std::ranges::ssize), const SizeMember&>);
31
32 struct SizeFunction {
size(SizeFunction)33 friend constexpr size_t size(SizeFunction) { return 42; }
34 };
35
36 struct SizeFunctionSigned {
size(SizeFunctionSigned)37 friend constexpr std::ptrdiff_t size(SizeFunctionSigned) { return 42; }
38 };
39
40 struct SizedSentinelRange {
41 int data_[2] = {};
beginSizedSentinelRange42 constexpr int *begin() { return data_; }
endSizedSentinelRange43 constexpr auto end() { return sized_sentinel<int*>(data_ + 2); }
44 };
45
46 struct ShortUnsignedReturnType {
sizeShortUnsignedReturnType47 constexpr unsigned short size() { return 42; }
48 };
49
50 // size_t changes depending on the platform.
51 using SignedSizeT = std::make_signed_t<size_t>;
52
test()53 constexpr bool test() {
54 int a[4];
55
56 assert(std::ranges::ssize(a) == 4);
57 ASSERT_SAME_TYPE(decltype(std::ranges::ssize(a)), SignedSizeT);
58
59 assert(std::ranges::ssize(SizeMember()) == 42);
60 ASSERT_SAME_TYPE(decltype(std::ranges::ssize(SizeMember())), SignedSizeT);
61
62 assert(std::ranges::ssize(SizeFunction()) == 42);
63 ASSERT_SAME_TYPE(decltype(std::ranges::ssize(SizeFunction())), SignedSizeT);
64
65 assert(std::ranges::ssize(SizeFunctionSigned()) == 42);
66 ASSERT_SAME_TYPE(decltype(std::ranges::ssize(SizeFunctionSigned())), std::ptrdiff_t);
67
68 SizedSentinelRange b;
69 assert(std::ranges::ssize(b) == 2);
70 ASSERT_SAME_TYPE(decltype(std::ranges::ssize(b)), std::ptrdiff_t);
71
72 // This gets converted to ptrdiff_t because it's wider.
73 ShortUnsignedReturnType c;
74 assert(std::ranges::ssize(c) == 42);
75 ASSERT_SAME_TYPE(decltype(std::ranges::ssize(c)), ptrdiff_t);
76
77 return true;
78 }
79
80 // Test ADL-proofing.
81 struct Incomplete;
82 template<class T> struct Holder { T t; };
83 static_assert(!std::is_invocable_v<RangeSSizeT, Holder<Incomplete>*>);
84 static_assert(!std::is_invocable_v<RangeSSizeT, Holder<Incomplete>*&>);
85
main(int,char **)86 int main(int, char**) {
87 test();
88 static_assert(test());
89
90 return 0;
91 }
92