STYLE: Prefer using the ITK_TRY_EXPECT macros in tests

Use the `ITK_TRY_EXPECT_EXCEPTION` and the `ITK_TRY_EXPECT_NO_EXCEPTION`
macros in tests in lieu of `try/catch` blocks for the sake of
readability and compactness, and to save typing/avoid boilerplate code.

Modules/IO/ImageBase/test/itkImageFileReaderTest1.cxx

@@ -17,6 +17,7 @@
  *=========================================================================*/
 
 #include "itkImageFileReader.h"
+#include "itkTestingMacros.h"
 
 
 int
@@ -33,65 +34,19 @@ itkImageFileReaderTest1(int argc, char * argv[])
   using ReaderType = itk::ImageFileReader<ImageNDType>;
 
   // Try an empty read
-  int status = 1;
-  try
-  {
-    auto reader = ReaderType::New();
-    reader->Update();
-  }
-  catch (const itk::ExceptionObject & ex)
-  {
-    std::cout << "------------------ Caught expected exception!" << std::endl;
-    std::cout << ex;
-    status = 0;
-  }
-  if (status)
-  {
-    std::cout << "Failed to catch expected exception." << std::endl;
-    return EXIT_FAILURE;
-  }
+  auto reader = ReaderType::New();
+  ITK_TRY_EXPECT_EXCEPTION(reader->Update());
 
 
   // Now try a read with an image that doesn't exist
-  status = 1;
-  try
-  {
-    auto reader = ReaderType::New();
-    reader->SetFileName("this_file_should_not_exist");
-    reader->Update();
-  }
-  catch (const itk::ExceptionObject & ex)
-  {
-    std::cout << "------------------ Caught expected exception!" << std::endl;
-    std::cout << ex;
-    status = 0;
-  }
-  if (status)
-  {
-    std::cout << "Failed to catch expected exception." << std::endl;
-    return EXIT_FAILURE;
-  }
+  reader->SetFileName("this_file_should_not_exist");
+  ITK_TRY_EXPECT_EXCEPTION(reader->Update());
+
 
   // Let's try to read a file where no ImageIO can read it
-  status = 1;
-  try
-  {
-    auto reader = ReaderType::New();
-    // this is the executable and no reader should be able to read it
-    reader->SetFileName(argv[0]);
-    reader->Update();
-  }
-  catch (const itk::ExceptionObject & ex)
-  {
-    std::cout << "------------------ Caught expected exception!" << std::endl;
-    std::cout << ex;
-    status = 0;
-  }
-  if (status)
-  {
-    std::cout << "Failed to catch expected exception." << std::endl;
-    return EXIT_FAILURE;
-  }
+  // This is the executable and no reader should be able to read it
+  reader->SetFileName(argv[0]);
+  ITK_TRY_EXPECT_EXCEPTION(reader->Update());
 
 
   return EXIT_SUCCESS;

Modules/Registration/RegistrationMethodsv4/test/itkImageRegistrationSamplingTest.cxx

@@ -17,6 +17,7 @@
  *=========================================================================*/
 
 #include "itkImageRegistrationMethodv4.h"
+#include "itkTestingMacros.h"
 
 /*
  * Test the SetMetricSamplingPercentage and SetMetricSamplingPercentagePerLevel.
@@ -33,29 +34,14 @@ itkImageRegistrationSamplingTest(int, char *[])
   using RegistrationType = itk::ImageRegistrationMethodv4<FixedImageType, MovingImageType>;
   auto registrationMethod = RegistrationType::New();
 
-  try
-  {
-    registrationMethod->SetMetricSamplingPercentage(0.1);
-  }
-  catch (const itk::ExceptionObject & e)
-  {
-    std::cerr << "Unexpected exception caught: " << e << std::endl;
-    return EXIT_FAILURE;
-  }
+  ITK_TRY_EXPECT_NO_EXCEPTION(registrationMethod->SetMetricSamplingPercentage(0.1));
+
 
   constexpr unsigned int     NUM_ERRORS = 3;
   RegistrationType::RealType errorValues[NUM_ERRORS] = { -0.1, 0.0, 1.1 };
   for (double errorValue : errorValues)
   {
-    try
-    {
-      registrationMethod->SetMetricSamplingPercentage(errorValue);
-      return EXIT_FAILURE;
-    }
-    catch (const itk::ExceptionObject &)
-    {
-      std::cerr << "Caught expected exception." << std::endl;
-    }
+    ITK_TRY_EXPECT_EXCEPTION(registrationMethod->SetMetricSamplingPercentage(errorValue));
   }
   return EXIT_SUCCESS;
 }

Modules/Registration/RegistrationMethodsv4/test/itkSimpleImageRegistrationTest4.cxx

@@ -137,15 +137,8 @@ ImageRegistration(int itkNotUsed(argc), char * argv[])
   auto observer = CommandType::New();
   optimizer->AddObserver(itk::IterationEvent(), observer);
 
-  try
-  {
-    registration->Update();
-  }
-  catch (const itk::ExceptionObject & e)
-  {
-    std::cerr << "Exception caught: " << e << std::endl;
-    return EXIT_FAILURE;
-  }
+  ITK_TRY_EXPECT_NO_EXCEPTION(registration->Update());
+
 
   registration->GetTransform()->Print(std::cout);
   std::cout << optimizer->GetStopConditionDescription() << std::endl;

Modules/Registration/RegistrationMethodsv4/test/itkSimplePointSetRegistrationTest.cxx

@@ -228,16 +228,8 @@ itkSimplePointSetRegistrationTest(int itkNotUsed(argc), char * itkNotUsed(argv)[
   auto affineObserver = AffineCommandType::New();
   affineSimple->AddObserver(itk::MultiResolutionIterationEvent(), affineObserver);
 
-  try
-  {
-    std::cout << "Point set affine registration update" << std::endl;
-    affineSimple->Update();
-  }
-  catch (const itk::ExceptionObject & e)
-  {
-    std::cerr << "Exception caught: " << e << std::endl;
-    return EXIT_FAILURE;
-  }
+  ITK_TRY_EXPECT_NO_EXCEPTION(affineSimple->Update());
+
 
   // applying the resultant transform to moving points and verify result
   std::cout << "Fixed\tMoving\tMovingTransformed\tFixedTransformed\tDiff" << std::endl;