[test] add 1x1 matrix type equality

linalg/eigen/fcarouge/linalg.hpp

@@ -83,6 +83,12 @@ inline const auto identity_v<Matrix>{Matrix::Identity()};
 //! @brief The zero matrix Eigen specialization.
 template <eigen Matrix> inline const auto zero_v<Matrix>{Matrix::Zero()};
 //! @}
+
+template <typename Type>
+[[nodiscard]] inline bool operator==(const matrix<Type, 1, 1> &lhs,
+                                     const Type &rhs) {
+  return lhs(0, 0) == rhs;
+}
 } // namespace fcarouge
 
 #endif // FCAROUGE_LINALG_HPP

test/CMakeLists.txt

@@ -79,6 +79,7 @@ foreach(BACKEND IN ITEMS "eigen" "lazy" "naive")
     "linalg_multiplication_rxc.cpp"
     "linalg_multiplication_sxc.cpp"
     "linalg_operator_bracket.cpp"
+    "linalg_operator_equality_1x1.cpp"
     "linalg_operator_equality.cpp"
     "linalg_zero_default.cpp"
     "linalg_zero.cpp")

test/linalg_operator_equality_1x1.cpp

@@ -0,0 +1,56 @@
+/*  __          _      __  __          _   _
+| |/ /    /\   | |    |  \/  |   /\   | \ | |
+| ' /    /  \  | |    | \  / |  /  \  |  \| |
+|  <    / /\ \ | |    | |\/| | / /\ \ | . ` |
+| . \  / ____ \| |____| |  | |/ ____ \| |\  |
+|_|\_\/_/    \_\______|_|  |_/_/    \_\_| \_|
+
+Kalman Filter
+Version 0.2.0
+https://github.com/FrancoisCarouge/Kalman
+
+SPDX-License-Identifier: Unlicense
+
+This is free and unencumbered software released into the public domain.
+
+Anyone is free to copy, modify, publish, use, compile, sell, or
+distribute this software, either in source code form or as a compiled
+binary, for any purpose, commercial or non-commercial, and by any
+means.
+
+In jurisdictions that recognize copyright laws, the author or authors
+of this software dedicate any and all copyright interest in the
+software to the public domain. We make this dedication for the benefit
+of the public at large and to the detriment of our heirs and
+successors. We intend this dedication to be an overt act of
+relinquishment in perpetuity of all present and future rights to this
+software under copyright law.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+For more information, please refer to <https://unlicense.org> */
+
+#include "fcarouge/linalg.hpp"
+
+#include <cassert>
+
+namespace fcarouge::test {
+namespace {
+//! @test Verifies the 1x1 matrix equates to its element type.
+//!
+//! @todo Rewrite this test as a property-based test.
+[[maybe_unused]] auto test{[] {
+  matrix<double, 1, 1> m{42.0};
+
+  assert(m == 42.0);
+
+  return 0;
+}()};
+} // namespace
+} // namespace fcarouge::test