From e6f263161966283368a3628fcae96376e875381e Mon Sep 17 00:00:00 2001
From: Paul Gessinger <paul.gessinger@cern.ch>
Date: Tue, 12 Nov 2024 14:20:25 +0100
Subject: [PATCH 1/2] feat: Add optional context type getter

Also adds a unit test.
---
 .../Acts/Utilities/detail/ContextType.hpp     | 22 ++++++++++++
 Tests/UnitTests/Core/Utilities/CMakeLists.txt |  1 +
 .../Core/Utilities/ContextTypeTests.cpp       | 36 +++++++++++++++++++
 3 files changed, 59 insertions(+)
 create mode 100644 Tests/UnitTests/Core/Utilities/ContextTypeTests.cpp

diff --git a/Core/include/Acts/Utilities/detail/ContextType.hpp b/Core/include/Acts/Utilities/detail/ContextType.hpp
index 143e8b2d521..8ccadd77c4d 100644
--- a/Core/include/Acts/Utilities/detail/ContextType.hpp
+++ b/Core/include/Acts/Utilities/detail/ContextType.hpp
@@ -79,6 +79,28 @@ class ContextType {
     return std::any_cast<const std::decay_t<T>&>(m_data);
   }
 
+  /// Retrieve a pointer to the contained type
+  ///
+  /// @note Returns `nullptr` if @p is not the contained type.
+  ///
+  /// @tparam T The type to attempt to retrieve the value as
+  /// @return Pointer to the contained value, may be null
+  template <typename T>
+  std::decay_t<T>* maybeGet() {
+    return std::any_cast<std::decay_t<T>>(&m_data);
+  }
+
+  /// Retrieve a pointer to the contained type
+  ///
+  /// @note Returns `nullptr` if @p is not the contained type.
+  ///
+  /// @tparam T The type to attempt to retrieve the value as
+  /// @return Pointer to the contained value, may be null
+  template <typename T>
+  const std::decay_t<T>* maybeGet() const {
+    return std::any_cast<const std::decay_t<T>>(&m_data);
+  }
+
   /// Check if the contained type is initialized.
   /// @return Boolean indicating whether a type is present
   bool hasValue() const { return m_data.has_value(); }
diff --git a/Tests/UnitTests/Core/Utilities/CMakeLists.txt b/Tests/UnitTests/Core/Utilities/CMakeLists.txt
index cb5249b6be9..955b58b31c9 100644
--- a/Tests/UnitTests/Core/Utilities/CMakeLists.txt
+++ b/Tests/UnitTests/Core/Utilities/CMakeLists.txt
@@ -61,3 +61,4 @@ add_unittest(VectorHelpers VectorHelpersTests.cpp)
 
 add_unittest(TrackHelpers TrackHelpersTests.cpp)
 add_unittest(GraphViz GraphVizTests.cpp)
+add_unittest(ContextType ContextTypeTests.cpp)
diff --git a/Tests/UnitTests/Core/Utilities/ContextTypeTests.cpp b/Tests/UnitTests/Core/Utilities/ContextTypeTests.cpp
new file mode 100644
index 00000000000..9ae43a7fbd9
--- /dev/null
+++ b/Tests/UnitTests/Core/Utilities/ContextTypeTests.cpp
@@ -0,0 +1,36 @@
+// This file is part of the ACTS project.
+//
+// Copyright (C) 2016 CERN for the benefit of the ACTS project
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+#include <boost/test/tools/old/interface.hpp>
+#include <boost/test/unit_test.hpp>
+
+#include "Acts/Utilities/detail/ContextType.hpp"
+
+using namespace Acts;
+
+BOOST_AUTO_TEST_SUITE(ContextTypeTests)
+
+BOOST_AUTO_TEST_CASE(PackUnpack) {
+  ContextType ctx;
+
+  ctx = int(42);
+
+  BOOST_CHECK_EQUAL(ctx.get<int>(), 42);
+  BOOST_CHECK_THROW(ctx.get<double>(), std::bad_any_cast);
+}
+
+BOOST_AUTO_TEST_CASE(MaybeUnpack) {
+  ContextType ctx;
+
+  ctx = int(42);
+
+  BOOST_CHECK_EQUAL(*ctx.maybeGet<int>(), 42);
+  BOOST_CHECK_EQUAL(ctx.maybeGet<double>(), nullptr);
+}
+
+BOOST_AUTO_TEST_SUITE_END()

From 7d86ae1a99be1a2748c775dbf36303e392cf5935 Mon Sep 17 00:00:00 2001
From: Paul Gessinger <paul.gessinger@cern.ch>
Date: Tue, 12 Nov 2024 15:37:13 +0100
Subject: [PATCH 2/2] avoid clang-tidy issue

---
 Tests/UnitTests/Core/Utilities/ContextTypeTests.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Tests/UnitTests/Core/Utilities/ContextTypeTests.cpp b/Tests/UnitTests/Core/Utilities/ContextTypeTests.cpp
index 9ae43a7fbd9..2bd67ee1e5f 100644
--- a/Tests/UnitTests/Core/Utilities/ContextTypeTests.cpp
+++ b/Tests/UnitTests/Core/Utilities/ContextTypeTests.cpp
@@ -18,7 +18,8 @@ BOOST_AUTO_TEST_SUITE(ContextTypeTests)
 BOOST_AUTO_TEST_CASE(PackUnpack) {
   ContextType ctx;
 
-  ctx = int(42);
+  int v = 42;
+  ctx = v;
 
   BOOST_CHECK_EQUAL(ctx.get<int>(), 42);
   BOOST_CHECK_THROW(ctx.get<double>(), std::bad_any_cast);
@@ -27,7 +28,8 @@ BOOST_AUTO_TEST_CASE(PackUnpack) {
 BOOST_AUTO_TEST_CASE(MaybeUnpack) {
   ContextType ctx;
 
-  ctx = int(42);
+  int v = 42;
+  ctx = v;
 
   BOOST_CHECK_EQUAL(*ctx.maybeGet<int>(), 42);
   BOOST_CHECK_EQUAL(ctx.maybeGet<double>(), nullptr);