[libc++][test] Do not assume array::iterator is a pointer (#100603)

In the tests I added for `ranges::find_last{_if{_not}}`, I accidentally
introduced an assumption that `same_as<array<T, 0>::iterator, T*>`; this
is a faulty assumption on MSVC-STL.

Fixes #100498.

3 files changed, 30 insertions, 10 deletions

diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last.pass.cpp
index 2a2b12f..9da8c26 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last.pass.cpp
@@ -25,6 +25,7 @@
 #include <algorithm>
 #include <array>
 #include <cassert>
+#include <memory>
 #include <ranges>
 #include <vector>
 
@@ -61,7 +62,8 @@ template <class It, class Sent = It>
 constexpr void test_iterators() {
   using ValueT    = std::iter_value_t<It>;
   auto make_range = [](auto& a) {
-    return std::ranges::subrange(It(std::ranges::begin(a)), Sent(It(std::ranges::end(a))));
+    return std::ranges::subrange(
+        It(std::to_address(std::ranges::begin(a))), Sent(It(std::to_address(std::ranges::end(a)))));
   };
   { // simple test
     {
@@ -91,7 +93,7 @@ constexpr void test_iterators() {
       std::array<ValueT, 0> a = {};
 
       auto ret = std::ranges::find_last(make_range(a), 1).begin();
-      assert(ret == It(a.begin()));
+      assert(ret == It(a.data()));
     }
   }
 
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last_if.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last_if.pass.cpp
index a15f81b..107fcf9 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last_if.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last_if.pass.cpp
@@ -92,14 +92,14 @@ constexpr void test_iterator_classes() {
     {
       std::array<int, 0> a = {};
 
-      auto ret = std::ranges::find_last_if(it(a.data()), sent(it(a.data())), [](auto&&) { return true; }).begin();
-      assert(ret == it(a.data()));
+      auto ret = std::ranges::find_last_if(it(a.begin()), sent(it(a.end())), [](auto&&) { return true; }).begin();
+      assert(ret == it(a.end()));
     }
     {
       std::array<int, 0> a = {};
 
       auto ret = std::ranges::find_last_if(make_range<it, sent>(a), [](auto&&) { return true; }).begin();
-      assert(ret == it(a.begin()));
+      assert(ret == it(a.end()));
     }
   }
 
@@ -183,8 +183,17 @@ struct NonConstComparable {
   friend constexpr bool operator==(NonConstComparable&, const NonConstComparable&) { return true; }
 };
 
+// TODO: this should really use `std::const_iterator`
 template <class T>
-using add_const_to_ptr_t = std::add_pointer_t<std::add_const_t<std::remove_pointer_t<T>>>;
+struct add_const_to_ptr {
+  using type = T;
+};
+template <class T>
+struct add_const_to_ptr<T*> {
+  using type = const T*;
+};
+template <class T>
+using add_const_to_ptr_t = typename add_const_to_ptr<T>::type;
 
 constexpr bool test() {
   test_iterator_classes<std::type_identity_t, std::type_identity_t>();
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last_if_not.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last_if_not.pass.cpp
index bb0e411..6602ac5 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last_if_not.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.last/ranges.find_last_if_not.pass.cpp
@@ -92,14 +92,14 @@ constexpr void test_iterator_classes() {
     {
       std::array<int, 0> a = {};
 
-      auto ret = std::ranges::find_last_if_not(it(a.data()), sent(it(a.data())), [](auto&&) { return false; }).begin();
-      assert(ret == it(a.data()));
+      auto ret = std::ranges::find_last_if_not(it(a.begin()), sent(it(a.end())), [](auto&&) { return false; }).begin();
+      assert(ret == it(a.end()));
     }
     {
       std::array<int, 0> a = {};
 
       auto ret = std::ranges::find_last_if_not(make_range<it, sent>(a), [](auto&&) { return false; }).begin();
-      assert(ret == it(a.begin()));
+      assert(ret == it(a.end()));
     }
   }
 
@@ -183,8 +183,17 @@ struct NonConstComparable {
   friend constexpr bool operator!=(NonConstComparable&, const NonConstComparable&) { return false; }
 };
 
+// TODO: this should really use `std::const_iterator`
 template <class T>
-using add_const_to_ptr_t = std::add_pointer_t<std::add_const_t<std::remove_pointer_t<T>>>;
+struct add_const_to_ptr {
+  using type = T;
+};
+template <class T>
+struct add_const_to_ptr<T*> {
+  using type = const T*;
+};
+template <class T>
+using add_const_to_ptr_t = typename add_const_to_ptr<T>::type;
 
 constexpr bool test() {
   test_iterator_classes<std::type_identity_t, std::type_identity_t>();