random access iterator test

Author: changkhothuychung

libcxx/test/std/ranges/range.adaptors/range.concat/iterator/random_acess.pass.cpp

@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+// REQUIRES: has-unix-headers, std-at-least-c++26
+
+#include <ranges>
+#include <cassert>
+#include <vector>
+
+constexpr bool test() {
+  std::vector<int> v1 = {1, 2, 3};
+  std::vector<int> v2 = {4, 5, 6};
+  auto cv             = std::views::concat(v1, v2);
+  static_assert(std::random_access_iterator<decltype(cv.begin())>);
+  assert(cv[0] == 1);
+  assert(cv[2] == 3);
+  assert(cv[3] == 4);
+  assert(cv[5] == 6);
+  return true;
+}
+
+int main(int, char**) {
+  test();
+  static_assert(test());
+
+  return 0;
+}