ENH: Make ITKDCMTK a private dependency of ITKIODCMTK

Move itkDCMTKFileReader.h from include/ to src/ so DCMTK types
(DcmStack, E_TransferSyntax, DcmDictEntry, etc.) do not appear in
public headers. Add PRIVATE include dir in src/CMakeLists.txt and
src/ include path in test/CMakeLists.txt for the test that exercises
DCMTKFileReader directly. Change itk-module.cmake to list ITKDCMTK
under PRIVATE_DEPENDS instead of DEPENDS.

Author: blowekamp

Modules/IO/DCMTK/itk-module.cmake

@@ -9,6 +9,7 @@ itk_module(
   ENABLE_SHARED
   DEPENDS
     ITKIOImageBase
+  PRIVATE_DEPENDS
     ITKDCMTK
   TEST_DEPENDS
     ITKTestKernel

Modules/IO/DCMTK/src/CMakeLists.txt

@@ -10,6 +10,10 @@ itk_module_add_library(
   ITKIODCMTK
   ${ITKIODCMTK_SRC}
 )
+
+# itkDCMTKFileReader.h is an internal header in this directory (not installed).
+target_include_directories(ITKIODCMTK PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
+
 if(DEFINED DCMTK_HAVE_CONFIG_H_OPTIONAL AND NOT DCMTK_HAVE_CONFIG_H_OPTIONAL)
   # Workaround Debian packaging issue - See FindDCMTK.cmake for more details
   target_compile_definitions(ITKIODCMTK PRIVATE ${DCMTK_DEFINITIONS})

…es/IO/DCMTK/include/itkDCMTKFileReader.h Modules/IO/DCMTK/src/itkDCMTKFileReader.hModules/IO/DCMTK/include/itkDCMTKFileReader.h renamed to Modules/IO/DCMTK/src/itkDCMTKFileReader.h Modules/IO/DCMTK/include/itkDCMTKFileReader.h renamed to Modules/IO/DCMTK/src/itkDCMTKFileReader.h

@@ -18,11 +18,20 @@ set(
 
 createtestdriver(ITKIODCMTK "${ITKIODCMTK-Test_LIBRARIES}" "${ITKIODCMTKTests}")
 
-# itkDCMTKFileReader.h transitively #include's dcmtk/dcmdata/*.h.  ITKIODCMTK
-# declares ITKDCMTK as a PRIVATE_DEPENDS (so consumers don't see DCMTK
-# headers), but the test driver consumes the public itkDCMTKFileReader.h
-# directly and therefore needs the DCMTK include path on its compile line.
-# Tracks issue #3820.  Reconstruct the include path the same way
+# itkDCMTKFileReader.h is a private implementation header in src/ (not
+# installed).  itkDCMTKGetDicomTagsTest.cxx includes it directly, so the test
+# driver needs the src/ directory on its compile line.
+target_include_directories(
+  ITKIODCMTKTestDriver
+  PRIVATE
+    "${CMAKE_CURRENT_SOURCE_DIR}/../src"
+)
+
+# itkDCMTKFileReader.h transitively #include's dcmtk/dcmdata/*.h.  ITKDCMTK
+# is a PRIVATE_DEPENDS of ITKIODCMTK (so consumers don't see DCMTK headers),
+# but the test driver includes itkDCMTKFileReader.h directly and therefore
+# needs the DCMTK include path on its compile line.
+# Reconstruct the include path the same way
 # Modules/ThirdParty/DCMTK/CMakeLists.txt populates ITKDCMTK_INCLUDE_DIRS,
 # since that variable is not in scope here.
 if(NOT ITK_USE_SYSTEM_DCMTK)