The default VTK_DATA_ROOT is not assigned dynamically in vtkTestUtilities.h
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
In the current version of vtkTestUtilities.h, the default VTK_DATA_ROOT is not assigned dynamically during the CMake generation process. Instead it is assigned to "../../../../VTKData". While this facilitates easy testing for any code in the VTK directory tree, projects wishing to use the VTK_DATA_ROOT outside the VTK tree are unable to.
A possible fix for this (I think) is to mv vtkTestUtilities.h to vtkTestUtilities.h.in and change instances of "../../../../VTKData" to "@VTK_DATA_ROOT@". Then add a line to the CMakeLists.txt: CONFIGURE_FILE(vtkTestUtilities.h.in vtkTestUtilities.h)