[wpimath] Add remaining struct and protobuf implementations (#5953)

wpimath/src/test/native/cpp/struct/MatrixStructTest.cpp

@@ -0,0 +1,23 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include <gtest/gtest.h>
+
+#include "../StructTestBase.h"
+#include "frc/EigenCore.h"
+#include "frc/struct/MatrixStruct.h"
+
+using namespace frc;
+
+struct MatrixStructTestData {
+  using Type = Matrixd<2, 3>;
+
+  inline static const Type kTestData{{1.1, 1.2, 1.3}, {1.4, 1.5, 1.6}};
+
+  static void CheckEq(const Type& testData, const Type& data) {
+    EXPECT_EQ(testData, data);
+  }
+};
+
+INSTANTIATE_TYPED_TEST_SUITE_P(Matrix, StructTest, MatrixStructTestData);