fixup! WIP: [libc++][ranges] Implement ranges::stride_view.

Cleanup another stride_view::end test.

Signed-off-by: Will Hawkins <[email protected]>

Author: hawkinsw

libcxx/test/std/ranges/range.adaptors/range.stride.view/end.pass.cpp

@@ -42,32 +42,28 @@ static_assert(HasConstAndNonConstEnd<std::ranges::stride_view<UnSimpleConstView>
 constexpr bool test_non_default_sentinel() {
   {
     const int data[3] = {1, 2, 3};
-    static_assert(simple_view<BasicTestView<int*, int*>>);
-    static_assert(std::ranges::common_range<BasicTestView<int*, int*>>);
-    static_assert(std::ranges::sized_range<BasicTestView<int*, int*>>);
-    static_assert(std::ranges::forward_range<BasicTestView<int*, int*>>);
-
     // A const, simple, common-, sized- and forward-range
+    // Note: sized because it is possible to get a difference between its
+    // beginning and its end.
     auto v  = BasicTestView<const int*, const int*>{data, data + 3};
     auto sv = std::ranges::stride_view<BasicTestView<const int*, const int*>>(v, 1);
     static_assert(!std::is_same_v<std::default_sentinel_t, decltype(sv.end())>);
   }
 
   {
     int data[3] = {1, 2, 3};
-    // TODO: start here.
-    using x = BasicTestView<forward_iterator<int*>, forward_iterator<int*>, false>;
-    static_assert(simple_view<BasicTestView<forward_iterator<int*>>>);
-    static_assert(std::ranges::common_range<x>);
-    static_assert(!std::ranges::sized_range<x>);
-    static_assert(!std::ranges::bidirectional_range<x>);
-
-    auto v  = x{forward_iterator(data), forward_iterator(data + 3)};
-    auto sv = std::ranges::stride_view<x>(v, 1);
+    // ForwardTestView is not sized and not bidirectional, but it is common.
+    // Note: It is not sized because BasicTestView has no member function named size (by default)
+    // and nor is it possible to get a difference between its beginning and its end.
+    using ForwardTestView = BasicTestView<forward_iterator<int*>, forward_iterator<int*>>;
+
+    auto v  = ForwardTestView{forward_iterator(data), forward_iterator(data + 3)};
+    auto sv = std::ranges::stride_view<ForwardTestView>(v, 1);
     static_assert(!std::is_same_v<std::default_sentinel_t, decltype(sv.end())>);
   }
 
   {
+    // TODO: Start here.
     static_assert(!simple_view<UnSimpleNoConstCommonView>);
     static_assert(std::ranges::common_range<UnSimpleNoConstCommonView>);
     static_assert(std::ranges::sized_range<UnSimpleNoConstCommonView>);