test: view CTAD

Author: PaulXiCao

libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/ctad.compile.pass.cpp

@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+
+// template <class... Vs>
+// cartesian_product_view(Vs&&...) -> cartesian_product_view<views::all_t<Vs>...>;
+
+#include <cassert>
+#include <ranges>
+#include <utility>
+
+struct Container {
+  int* begin() const;
+  int* end() const;
+};
+
+struct View : std::ranges::view_base {
+  int* begin() const;
+  int* end() const;
+};
+
+void testCTAD() {
+  static_assert(std::is_same_v<decltype(std::ranges::cartesian_product_view(Container{})),
+                               std::ranges::cartesian_product_view<std::ranges::owning_view<Container>>>);
+
+  static_assert(std::is_same_v<decltype(std::ranges::cartesian_product_view(Container{}, View{})),
+                               std::ranges::cartesian_product_view<std::ranges::owning_view<Container>, View>>);
+
+  Container c{};
+  static_assert(
+      std::is_same_v<
+          decltype(std::ranges::cartesian_product_view(Container{}, View{}, c)),
+          std::ranges::
+              cartesian_product_view<std::ranges::owning_view<Container>, View, std::ranges::ref_view<Container>>>);
+}