From 5bc8e7a6727f3845a099ea38e215cd342ade89fe Mon Sep 17 00:00:00 2001
From: Wolfgang Bangerth <bangerth@colostate.edu>
Date: Tue, 23 Jan 2024 18:43:17 -0700
Subject: [PATCH] Add a test.

---
 tests/sacado/tensor_01.cc     | 38 +++++++++++++++++++++++++++++++++++
 tests/sacado/tensor_01.output |  2 ++
 2 files changed, 40 insertions(+)
 create mode 100644 tests/sacado/tensor_01.cc
 create mode 100644 tests/sacado/tensor_01.output

diff --git a/tests/sacado/tensor_01.cc b/tests/sacado/tensor_01.cc
new file mode 100644
index 0000000000..d5d21b21be
--- /dev/null
+++ b/tests/sacado/tensor_01.cc
@@ -0,0 +1,38 @@
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2016 - 2020 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// The deal.II library is free software; you can use it, redistribute
+// it, and/or modify it under the terms of the GNU Lesser General
+// Public License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+// The full text of the license can be found in the file LICENSE at
+// the top level of the deal.II distribution.
+//
+// ---------------------------------------------------------------------
+
+
+// Make sure we can implicitly convert a tensor of AD types to a
+// tensor of double. This required a bit of work under the hood
+// because Sacado's AD types cannot be implicitly converted to
+// doubles.
+
+#include "../tests.h"
+
+#include "../ad_common_tests/physics_functions_01.h"
+
+int
+main()
+{
+  initlog();
+
+  using ADNumberType =
+    AD::NumberTraits<double, AD::NumberTypes::sacado_dfad>::ad_type;
+
+  const Tensor<2, 2, ADNumberType> F;
+  Tensor<2, 2>                     x = F;
+
+  deallog << "OK" << std::endl;
+}
diff --git a/tests/sacado/tensor_01.output b/tests/sacado/tensor_01.output
new file mode 100644
index 0000000000..0fd8fc12f0
--- /dev/null
+++ b/tests/sacado/tensor_01.output
@@ -0,0 +1,2 @@
+
+DEAL::OK
-- 
2.39.5