[libcxx-commits] [libcxx] [libc++][ranges] Implement `ranges::stride_view`. (PR #65200)

[Will Hawkins via libcxx-commits]

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@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// ranges
+
+// std::views::stride_view
+
+#include "test.h"
+#include "test_convertible.h"
+#include <type_traits>
+
+constexpr bool test_no_default_ctor() {
+  // There is no default ctor for stride_view.
+  static_assert(!std::is_default_constructible_v<std::ranges::stride_view<BidirArrayView<int>>>);
+  return true;
+}
+
+constexpr bool test_no_implicit_ctor() {
+  // Test that the stride_view can only be explicitly constructed.
+  static_assert(!test_convertible<std::ranges::stride_view<ForwardArrayView<int>>, ForwardArrayView<int>, int>());
+  return true;
+}
+
+constexpr bool test_move_ctor() {
+  int arr[] = {1, 2, 3};
+  // Test that the stride_view ctor properly moves from the base (and works with a move-only type).
+  static_assert(!std::is_copy_constructible_v<MovedOnlyTrackedBasicView<int>>);
+  static_assert(std::is_move_constructible_v<MovedOnlyTrackedBasicView<int>>);
+
+  bool moved(false), copied(false);
+  MovedOnlyTrackedBasicView<int> mov(arr, arr + 3, &moved, &copied);
+  std::ranges::stride_view<MovedOnlyTrackedBasicView<int>> mosv(std::move(mov), 2);
+  assert(moved);
+  assert(!copied);
+  return true;
+}
+
+int main(int, char**) {
+  test_no_implicit_ctor();
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hawkinsw wrote:

I believe that this is addressed in 34c5b7b114f33e75f0a420a59a6e49c2dec0f50f

https://github.com/llvm/llvm-project/pull/65200