refactor: Add new concepts for Eigen types

Core/include/Acts/EventData/TrackStateProxy.hpp

@@ -16,6 +16,7 @@
 #include "Acts/EventData/TrackStateType.hpp"
 #include "Acts/EventData/Types.hpp"
 #include "Acts/Surfaces/Surface.hpp"
+#include "Acts/Utilities/EigenConcepts.hpp"
 #include "Acts/Utilities/HashedString.hpp"
 #include "Acts/Utilities/Helpers.hpp"
 
@@ -782,12 +783,11 @@ class TrackStateProxy {
   template <typename val_t, typename cov_t>
   void allocateCalibrated(const Eigen::DenseBase<val_t>& val,
                           const Eigen::DenseBase<cov_t>& cov)
-    requires(Eigen::PlainObjectBase<val_t>::RowsAtCompileTime > 0 &&
-             Eigen::PlainObjectBase<val_t>::RowsAtCompileTime <= eBoundSize &&
-             Eigen::PlainObjectBase<val_t>::RowsAtCompileTime ==
-                 Eigen::PlainObjectBase<cov_t>::RowsAtCompileTime &&
-             Eigen::PlainObjectBase<cov_t>::RowsAtCompileTime ==
-                 Eigen::PlainObjectBase<cov_t>::ColsAtCompileTime)
+    requires(Concepts::eigen_base_is_fixed_size<val_t> &&
+             Concepts::eigen_bases_have_same_num_rows<val_t, cov_t> &&
+             Concepts::eigen_base_is_square<cov_t> &&
+             Eigen::PlainObjectBase<val_t>::RowsAtCompileTime <=
+                 static_cast<std::underlying_type_t<BoundIndices>>(eBoundSize))
   {
     m_traj->template allocateCalibrated<
         Eigen::PlainObjectBase<val_t>::RowsAtCompileTime>(m_istate, val, cov);

Core/include/Acts/EventData/VectorMultiTrajectory.hpp

@@ -16,6 +16,7 @@
 #include "Acts/EventData/Types.hpp"
 #include "Acts/EventData/detail/DynamicColumn.hpp"
 #include "Acts/EventData/detail/DynamicKeyIterator.hpp"
+#include "Acts/Utilities/EigenConcepts.hpp"
 #include "Acts/Utilities/HashedString.hpp"
 #include "Acts/Utilities/Helpers.hpp"
 #include "Acts/Utilities/ThrowAssert.hpp"
@@ -495,13 +496,11 @@ class VectorMultiTrajectory final
   void allocateCalibrated_impl(IndexType istate,
                                const Eigen::DenseBase<val_t>& val,
                                const Eigen::DenseBase<cov_t>& cov)
-
-    requires(Eigen::PlainObjectBase<val_t>::RowsAtCompileTime > 0 &&
-             Eigen::PlainObjectBase<val_t>::RowsAtCompileTime <= eBoundSize &&
-             Eigen::PlainObjectBase<val_t>::RowsAtCompileTime ==
-                 Eigen::PlainObjectBase<cov_t>::RowsAtCompileTime &&
-             Eigen::PlainObjectBase<cov_t>::RowsAtCompileTime ==
-                 Eigen::PlainObjectBase<cov_t>::ColsAtCompileTime)
+    requires(Concepts::eigen_base_is_fixed_size<val_t> &&
+             Concepts::eigen_bases_have_same_num_rows<val_t, cov_t> &&
+             Concepts::eigen_base_is_square<cov_t> &&
+             Eigen::PlainObjectBase<val_t>::RowsAtCompileTime <=
+                 static_cast<std::underlying_type_t<BoundIndices>>(eBoundSize))
   {
     constexpr std::size_t measdim = val_t::RowsAtCompileTime;
 

Core/include/Acts/Utilities/EigenConcepts.hpp

@@ -0,0 +1,56 @@
+// 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/.
+
+#pragma once
+
+#include <Eigen/Dense>
+
+namespace Acts::Concepts {
+/// @brief Concept that is true iff T is a valid Eigen dense base.
+template <typename T>
+concept is_eigen_base = requires {
+  { T::RowsAtCompileTime };
+  { T::ColsAtCompileTime };
+};
+
+/// @brief Concept that is true iff T is a valid Eigen dense base with fixed
+/// size.
+template <typename T>
+concept eigen_base_is_fixed_size =
+    is_eigen_base<T> && Eigen::PlainObjectBase<T>::RowsAtCompileTime > 0 &&
+    Eigen::PlainObjectBase<T>::ColsAtCompileTime > 0;
+
+/// @brief Concept that is true iff T is a valid Eigen dense base with fixed,
+/// square size.
+template <typename T>
+concept eigen_base_is_square = eigen_base_is_fixed_size<T> &&
+                               Eigen::PlainObjectBase<T>::RowsAtCompileTime ==
+                                   Eigen::PlainObjectBase<T>::ColsAtCompileTime;
+
+/// @brief Concept that is true iff T1 and T2 have the same, known at compile
+/// time, number of rows.
+template <typename T1, typename T2>
+concept eigen_bases_have_same_num_rows =
+    eigen_base_is_fixed_size<T1> && eigen_base_is_fixed_size<T2> &&
+    static_cast<std::size_t>(Eigen::PlainObjectBase<T1>::RowsAtCompileTime) ==
+        static_cast<std::size_t>(Eigen::PlainObjectBase<T2>::RowsAtCompileTime);
+
+/// @brief Concept that is true iff T1 and T2 have the same, known at compile
+/// time, number of columns.
+template <typename T1, typename T2>
+concept eigen_bases_have_same_num_cols =
+    eigen_base_is_fixed_size<T1> && eigen_base_is_fixed_size<T2> &&
+    static_cast<std::size_t>(Eigen::PlainObjectBase<T1>::ColsAtCompileTime) ==
+        static_cast<std::size_t>(Eigen::PlainObjectBase<T2>::ColsAtCompileTime);
+
+/// @brief Concept that is true iff T1 and T2 have the same, known at compile
+/// time, size.
+template <typename T1, typename T2>
+concept eigen_bases_have_same_size = eigen_bases_have_same_num_rows<T1, T2> &&
+                                     eigen_bases_have_same_num_cols<T1, T2>;
+}  // namespace Acts::Concepts