Introduction of a new macro named "slicerMacroAddModuleCxxTestDriver" would help simplifying how test are written.
See http://slicer-devel.65872.n3.nabble.com/Proposal-Introduction-of-a-macro-named-quot-slicerMacroAddModuleCxxTestDriver-quot-tt4027573.html

Waiting for feedback from the community.

The following commits should resolve the last problem associated with Slicer tests.

That said, I thought about few different approaches:

1) Extent the "create_test_sourcelist" CMake command and add a parameter named EXTRA_INCLUDES. With that new feature it would then be easier to pass additional header to the test driver. Writing of macro like "slicerMacroAddModuleCxxTestDriver" would be easier.

2) Instead of trying to work around the issue, it would probably make sens to add such library into ITKv4 proper.

[1] http://www.cmake.org/cmake/help/v2.8.10/cmake.html#command:create_test_sourcelist

In the mean time, the solution is to include "itkFactoryRegistration.h" and call "itk::itkFactoryRegistration()"

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Commit r21721:

BUG: Ensure ITKv4 IO Factory are registered within tests

• Include directories associated with ITKFactoryRegistration are also
  appended to ITK_INLCUDE_DIRS to ensure that the method itk::itkFactoryRegistration
  could be called.

• Code allowing to register the factory has been manually added to the
  tests.

• Would it make sens to have this library ITKFactoryIORegistration
  being built/provided by ITKv4 proper ?

See http://viewvc.slicer.org/viewvc.cgi/Slicer4?view=revision&revision=21721
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Commit r21723:

COMP: Ensure ITKFactoryRegistration is considered when setting ITK_INCLUDE_DIRS at top-level.

This will fix build errors of the form:

.../Logic/Testing/Cxx/vtkMRMLSliceLogicTest2.cxx:49:38: error: itkFactoryRegistration.h: No such file or directory
.../Logic/Testing/Cxx/vtkMRMLSliceLogicTest2.cxx: In function 'int vtkMRMLSliceLogicTest2(int, char**)':
.../Logic/Testing/Cxx/vtkMRMLSliceLogicTest2.cxx:56: error: 'itkFactoryRegistration' is not a member of 'itk'

See http://viewvc.slicer.org/viewvc.cgi/Slicer4?view=revision&revision=21723
// ------------------------------------

// ------------------------------------
Commit r21725:

COMP: Fix missing "itkFactoryRegistrationConfigure.h" build error

This will fix build errors of the form:

../ITKFactoryRegistration/itkFactoryRegistration.h:6:45: error: itkFactoryRegistrationConfigure.h: No such file or directory
../Libs/MRML/Logic/Testing/Cxx/vtkMRMLSliceLogicTest2.cxx:49:
../Libs/ITKFactoryRegistration/itkFactoryRegistration.h:10: error: expected constructor, destructor, or type conversion before 'void'
../Libs/MRML/Logic/Testing/Cxx/vtkMRMLSliceLogicTest2.cxx: In function 'int vtkMRMLSliceLogicTest2(int, char**)':
../Libs/MRML/Logic/Testing/Cxx/vtkMRMLSliceLogicTest2.cxx:56: error: 'itkFactoryRegistration' is not a member of 'itk'

See http://viewvc.slicer.org/viewvc.cgi/Slicer4?view=revision&revision=21725
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