ENH: Add unit tests to increase coverage

test/CMakeLists.txt

@@ -17,6 +17,9 @@ set(
   itkCudaImageFromImageFilterTest.cxx
   itkCudaImageToImageFilterTest.cxx
   itkCudaMemoryProbeTest.cxx
+  itkCudaDataManagerDirtyFlagTest.cxx
+  itkCudaDataManagerReleaseFreeTest.cxx
+  itkCudaImageRegionGraftTest.cxx
 )
 
 createtestdriver(CudaCommon "${CudaCommon-Test_LIBRARIES}" "${CudaCommonTests}")
@@ -41,6 +44,21 @@ itk_add_test(NAME itkCudaMemoryProbeTest
   itkCudaMemoryProbeTest
 )
 
+itk_add_test(NAME itkCudaDataManagerDirtyFlagTest
+  COMMAND CudaCommonTestDriver
+  itkCudaDataManagerDirtyFlagTest
+)
+
+itk_add_test(NAME itkCudaDataManagerReleaseFreeTest
+  COMMAND CudaCommonTestDriver
+  itkCudaDataManagerReleaseFreeTest
+)
+
+itk_add_test(NAME itkCudaImageRegionGraftTest
+  COMMAND CudaCommonTestDriver
+  itkCudaImageRegionGraftTest
+)
+
 if(ITK_WRAP_PYTHON)
   itk_python_add_test(NAME itkCudaImageFromImagePythonTest
     COMMAND itkCudaImageFromImageTest.py

test/itkCudaDataManagerDirtyFlagTest.cxx

@@ -0,0 +1,77 @@
+/*=========================================================================
+ *
+ *  Copyright NumFOCUS
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *         https://www.apache.org/licenses/LICENSE-2.0.txt
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *=========================================================================*/
+
+#include "itkCudaDataManager.h"
+#include "itkTestingMacros.h"
+#include <cmath>
+#include <iostream>
+
+int
+itkCudaDataManagerDirtyFlagTest(int, char *[])
+{
+  constexpr size_t BUFFER_SIZE = 256 * sizeof(float);
+
+  auto mgr = itk::CudaDataManager::New();
+  mgr->SetBufferSize(BUFFER_SIZE);
+  mgr->Allocate();
+  auto * cpuBuf = new float[256];
+  mgr->SetCPUBufferPointer(cpuBuf);
+
+  // Both-dirty error in Update
+  mgr->SetCPUDirtyFlag(true);
+  mgr->SetGPUDirtyFlag(true);
+  ITK_TRY_EXPECT_EXCEPTION(mgr->Update());
+
+  // Update with GPU dirty only: re-allocates GPU buffer and copies CPU→GPU
+  mgr->SetGPUDirtyFlag(false);
+  mgr->SetCPUDirtyFlag(false);
+  for (int i = 0; i < 256; ++i)
+    cpuBuf[i] = static_cast<float>(i);
+  mgr->Update();              // sync both — GPU now holds {0,1,2,...}
+  mgr->SetGPUDirtyFlag(true); // frees GPU buffer
+  mgr->SetCPUDirtyFlag(false);
+  mgr->Update();
+  if (std::abs(cpuBuf[0] - 0.0f) >= 1e-6f)
+  {
+    std::cerr << "CPU buffer should be unchanged after CPU→GPU copy" << std::endl;
+    delete[] cpuBuf;
+    return EXIT_FAILURE;
+  }
+
+  // Update with CPU dirty only: copies GPU→CPU
+  mgr->SetCPUDirtyFlag(false);
+  mgr->SetGPUDirtyFlag(false);
+  for (int i = 0; i < 256; ++i)
+    cpuBuf[i] = static_cast<float>(i);
+  mgr->Update(); // sync both — GPU now holds {0,1,2,...}
+  for (int i = 0; i < 256; ++i)
+    cpuBuf[i] = 99.0f; // make CPU stale
+  mgr->SetCPUDirtyFlag(true);
+  mgr->SetGPUDirtyFlag(false);
+  mgr->Update();
+  if (std::abs(cpuBuf[0] - 0.0f) >= 1e-6f)
+  {
+    std::cerr << "CPU buffer should have GPU values after GPU→CPU copy" << std::endl;
+    delete[] cpuBuf;
+    return EXIT_FAILURE;
+  }
+  delete[] cpuBuf;
+
+  std::cout << "CudaDataManagerDirtyFlagTest passed" << std::endl;
+  return EXIT_SUCCESS;
+}

test/itkCudaDataManagerReleaseFreeTest.cxx

@@ -0,0 +1,53 @@
+/*=========================================================================
+ *
+ *  Copyright NumFOCUS
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *         https://www.apache.org/licenses/LICENSE-2.0.txt
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *=========================================================================*/
+
+#include "itkCudaDataManager.h"
+#include <iostream>
+
+int
+itkCudaDataManagerReleaseFreeTest(int, char *[])
+{
+  constexpr size_t BUFFER_SIZE = 256 * sizeof(float);
+
+  // SetGPUBufferDirty frees GPU memory when release is true (default)
+  auto mgr = itk::CudaDataManager::New();
+  mgr->SetBufferSize(BUFFER_SIZE);
+  mgr->Allocate();
+  mgr->SetGPUBufferDirty();
+  if (mgr->GetGPUBufferSize() != 0)
+  {
+    std::cerr << "GPU buffer should be freed after SetGPUBufferDirty" << std::endl;
+    return EXIT_FAILURE;
+  }
+
+  // SetGPUBufferDirty does not free when release is false
+  auto mgr2 = itk::CudaDataManager::New();
+  mgr2->SetReleaseDirtyGPUBuffer(false);
+  mgr2->SetBufferSize(BUFFER_SIZE);
+  mgr2->Allocate();
+  size_t before = mgr2->GetGPUBufferSize();
+  mgr2->SetGPUBufferDirty();
+  if (mgr2->GetGPUBufferSize() != before)
+  {
+    std::cerr << "GPU buffer should not be freed when release is false" << std::endl;
+    return EXIT_FAILURE;
+  }
+
+  std::cout << "CudaDataManagerReleaseFreeTest passed" << std::endl;
+  return EXIT_SUCCESS;
+}

test/itkCudaImageRegionGraftTest.cxx

@@ -0,0 +1,43 @@
+/*=========================================================================
+ *
+ *  Copyright NumFOCUS
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *         https://www.apache.org/licenses/LICENSE-2.0.txt
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *=========================================================================*/
+
+#include "itkCudaImage.h"
+#include <iostream>
+
+using CudaImage2f = itk::CudaImage<float, 2>;
+
+int
+itkCudaImageRegionGraftTest(int, char *[])
+{
+  auto img = CudaImage2f::New();
+  img->SetRegions(itk::MakeSize(32, 32));
+  img->Allocate();
+
+  // Initialize creates a new DataManager
+  auto * dmBefore = img->GetCudaDataManager().GetPointer();
+  img->Initialize();
+  auto * dmAfter = img->GetCudaDataManager().GetPointer();
+  if (dmBefore == dmAfter)
+  {
+    std::cerr << "Initialize should create a new DataManager" << std::endl;
+    return EXIT_FAILURE;
+  }
+
+  std::cout << "CudaImageRegionGraftTest passed" << std::endl;
+  return EXIT_SUCCESS;
+}