[libc++][ranges] LWG3610: iota_view::size sometimes rejects integer-class types

libcxx/docs/Status/Cxx23Issues.csv

@@ -143,7 +143,7 @@
 "`LWG3598 <https://wg21.link/LWG3598>`__","``system_category().default_error_condition(0)`` is underspecified","2022-02 (Virtual)","","",""
 "`LWG3601 <https://wg21.link/LWG3601>`__","common_iterator's postfix-proxy needs ``indirectly_readable`` ","2022-02 (Virtual)","","",""
 "`LWG3607 <https://wg21.link/LWG3607>`__","``contiguous_iterator`` should not be allowed to have custom ``iter_move`` and ``iter_swap`` behavior","2022-02 (Virtual)","|Nothing To Do|","",""
-"`LWG3610 <https://wg21.link/LWG3610>`__","``iota_view::size`` sometimes rejects integer-class types","2022-02 (Virtual)","","",""
+"`LWG3610 <https://wg21.link/LWG3610>`__","``iota_view::size`` sometimes rejects integer-class types","2022-02 (Virtual)","|Complete|","22",""
 "`LWG3612 <https://wg21.link/LWG3612>`__","Inconsistent pointer alignment in ``std::format`` ","2022-02 (Virtual)","|Complete|","14",""
 "`LWG3616 <https://wg21.link/LWG3616>`__","LWG 3498 seems to miss the non-member ``swap`` for ``basic_syncbuf`` ","2022-02 (Virtual)","|Complete|","18",""
 "`LWG3618 <https://wg21.link/LWG3618>`__","Unnecessary ``iter_move`` for ``transform_view::iterator`` ","2022-02 (Virtual)","|Complete|","19",""

libcxx/include/__ranges/iota_view.h

@@ -58,11 +58,17 @@ struct __get_wider_signed {
       return type_identity<int>{};
     else if constexpr (sizeof(_Int) < sizeof(long))
       return type_identity<long>{};
+    else if constexpr (sizeof(_Int) < sizeof(long long))
+      return type_identity<long long>{};
     else
+#  if _LIBCPP_HAS_INT128
+      return type_identity<__int128_t>{};
+#  else
       return type_identity<long long>{};
 
     static_assert(
         sizeof(_Int) <= sizeof(long long), "Found integer-like type that is bigger than largest integer like type.");
+#  endif
   }
 
   using type = typename decltype(__call())::type;
@@ -349,7 +355,7 @@ class iota_view : public view_interface<iota_view<_Start, _BoundSentinel>> {
 
   _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
     requires(same_as<_Start, _BoundSentinel> && __advanceable<_Start>) ||
-            (integral<_Start> && integral<_BoundSentinel>) || sized_sentinel_for<_BoundSentinel, _Start>
+            (__integer_like<_Start> && __integer_like<_BoundSentinel>) || sized_sentinel_for<_BoundSentinel, _Start>
   {
     if constexpr (__integer_like<_Start> && __integer_like<_BoundSentinel>) {
       return (__value_ < 0)

libcxx/test/std/ranges/range.factories/range.iota.view/begin.pass.cpp

@@ -40,6 +40,10 @@ constexpr void testType() {
 
 constexpr bool test() {
   testType<SomeInt>();
+#ifndef TEST_HAS_NO_INT128
+  testType<__int128_t>();
+  testType<__uint128_t>();
+#endif
   testType<long long>();
   testType<unsigned long long>();
   testType<signed long>();

libcxx/test/std/ranges/range.factories/range.iota.view/end.pass.cpp

@@ -61,6 +61,14 @@ constexpr void testType(U u) {
 constexpr bool test() {
   testType<SomeInt>(SomeInt(10));
   testType<SomeInt>(IntComparableWith(SomeInt(10)));
+#ifndef TEST_HAS_NO_INT128
+  testType<__int128_t>(__int128_t(10));
+  testType<__uint128_t>(__uint128_t(10));
+#endif
+  testType<signed long long>(10LL);
+  testType<unsigned long long>(10ULL);
+  testType<signed long long>(IntComparableWith<signed long long>(10));
+  testType<unsigned long long>(IntComparableWith<unsigned long long>(10));
   testType<signed long>(IntComparableWith<signed long>(10));
   testType<unsigned long>(IntComparableWith<unsigned long>(10));
   testType<int>(IntComparableWith<int>(10));

libcxx/test/std/ranges/range.factories/range.iota.view/iterator/member_typedefs.compile.pass.cpp

@@ -106,7 +106,11 @@ void test() {
     // Same as below, if there is no type larger than long, we can just use that.
     static_assert(sizeof(Iter::difference_type) >= sizeof(long));
     static_assert(std::is_signed_v<Iter::difference_type>);
+#ifdef TEST_HAS_NO_INT128
     LIBCPP_STATIC_ASSERT(std::same_as<Iter::difference_type, long long>);
+#else
+    LIBCPP_STATIC_ASSERT(std::same_as<Iter::difference_type, __int128_t>);
+#endif
   }
   {
     const std::ranges::iota_view<long long> io(0);
@@ -118,7 +122,11 @@ void test() {
     // https://eel.is/c++draft/range.iota.view#1.3
     static_assert(sizeof(Iter::difference_type) >= sizeof(long long));
     static_assert(std::is_signed_v<Iter::difference_type>);
+#ifdef TEST_HAS_NO_INT128
     LIBCPP_STATIC_ASSERT(std::same_as<Iter::difference_type, long long>);
+#else
+    LIBCPP_STATIC_ASSERT(std::same_as<Iter::difference_type, __int128_t>);
+#endif
   }
   {
     const std::ranges::iota_view<Decrementable> io;

libcxx/test/std/ranges/range.factories/range.iota.view/iterator/star.pass.cpp

@@ -81,6 +81,12 @@ constexpr void testType() {
 constexpr bool test() {
   testType<SomeInt>();
   testType<NotNoexceptCopy>();
+#ifndef TEST_HAS_NO_INT128
+  testType<__int128_t>();
+  testType<__uint128_t>();
+#endif
+  testType<signed long long>();
+  testType<unsigned long long>();
   testType<signed long>();
   testType<unsigned long>();
   testType<int>();

libcxx/test/std/ranges/range.factories/range.iota.view/iterator/subscript.pass.cpp

@@ -47,6 +47,12 @@ constexpr void testType() {
 
 constexpr bool test() {
   testType<SomeInt>();
+#ifndef TEST_HAS_NO_INT128
+  testType<__int128_t>();
+  testType<__uint128_t>();
+#endif
+  testType<signed long long>();
+  testType<unsigned long long>();
   testType<signed long>();
   testType<unsigned long>();
   testType<int>();

libcxx/test/std/ranges/range.factories/range.iota.view/size.pass.cpp

@@ -16,8 +16,21 @@
 #include <ranges>
 
 #include "test_macros.h"
+#include "type_algorithms.h"
 #include "types.h"
 
+template <typename T>
+concept HasSize = requires(const T t) { t.size(); };
+
+struct CheckForSize {
+  template <class IntegerLikeT>
+  constexpr void operator()() {
+    types::for_each(types::integer_types{}, []<typename BoundT>() {
+      static_assert(HasSize<std::ranges::iota_view<IntegerLikeT, BoundT>>);
+    });
+  }
+};
+
 constexpr bool test() {
   // Both are integer like and both are less than zero.
   {
@@ -99,6 +112,11 @@ constexpr bool test() {
     assert(sz == 10);
   }
 
+  // LWG3610: `iota_view::size` sometimes rejects integer-class types
+  {
+    types::for_each(types::integer_types{}, CheckForSize{});
+  }
+
   return true;
 }