ENH: Support "compiling" source file exclusively to .pyc

Introduce the option CTK_COMPILE_PYTHON_SCRIPT_SKIP_SCRIPT_COPY
to support disabling the copy of `*.py` script into the build
directory.

Update CMake function `ctkFunctionAddCompilePythonScriptTargets` to
accept a new parameter called `SKIP_SCRIPT_COPY`.

Address warning when using CMake >= 3.13, setting CMP0077 to NEW.
See https://cmake.org/cmake/help/latest/policy/CMP0077.html

Co-authored-by: Jean-Christophe Fillion-Robin <[email protected]>

CMake/CTKConfig.cmake.in

@@ -40,6 +40,7 @@ set(CTK_LIBRARY_DIRS ${CTK_LIBRARY_DIR})
 
 # CTK specific variables
 set(CTK_CMAKE_DEBUG_POSTFIX "@CMAKE_DEBUG_POSTFIX@")
+set(CTK_COMPILE_PYTHON_SCRIPT_SKIP_SCRIPT_COPY "@CTK_COMPILE_PYTHON_SCRIPT_SKIP_SCRIPT_COPY@")
 
 # Import CTK targets
 if(NOT TARGET CTKCore)

CMake/ctkMacroCompilePythonScript.cmake

@@ -21,6 +21,12 @@ include(${CTK_CMAKE_DIR}/ctkMacroParseArguments.cmake)
 
 set(CTK_PYTHON_COMPILE_FILE_SCRIPT_DIR "${CMAKE_BINARY_DIR}/CMakeFiles")
 
+# Setting this option to TRUE disable the copy of ".py" files into the
+# destination directory associated with ctkMacroCompilePythonScript.
+if(NOT DEFINED CTK_COMPILE_PYTHON_SCRIPT_SKIP_SCRIPT_COPY)
+  set(CTK_COMPILE_PYTHON_SCRIPT_SKIP_SCRIPT_COPY FALSE)
+endif()
+
 #! \ingroup CMakeAPI
 macro(ctkMacroCompilePythonScript)
   ctkMacroParseArguments(MY
@@ -98,7 +104,7 @@ macro(ctkMacroCompilePythonScript)
     USE_SOURCE_PERMISSIONS)
 
   if(NOT MY_GLOBAL_TARGET)
-    ctkFunctionAddCompilePythonScriptTargets(${target})
+    ctkFunctionAddCompilePythonScriptTargets(${target} ${CTK_COMPILE_PYTHON_SCRIPT_SKIP_SCRIPT_COPY})
   endif()
 endmacro()
 
@@ -182,8 +188,11 @@ function(_ctk_add_compile_python_directories_target target)
   endif()
 endfunction()
 
-function(ctkFunctionAddCompilePythonScriptTargets target)
-  _ctk_add_copy_python_files_target(${target} Script ${ARGN})
+function(ctkFunctionAddCompilePythonScriptTargets target SKIP_SCRIPT_COPY)
+  # Skip defining the target CopySlicerPythonScriptFiles when the argument SKIP_SCRIPT_COPY is set to True
+  if(NOT ${SKIP_SCRIPT_COPY})
+    _ctk_add_copy_python_files_target(${target} Script ${ARGN})
+  endif()
   _ctk_add_copy_python_files_target(${target} Resource ${ARGN})
   _ctk_add_compile_python_directories_target(${target})
 endfunction()

CMakeLists.txt

@@ -22,6 +22,7 @@ cmake_minimum_required(VERSION 3.0)
 
 foreach(p
   CMP0054 # CMake 3.1
+  CMP0077 # CMake 3.13
   )
   if(POLICY ${p})
     cmake_policy(SET ${p} NEW)
@@ -744,6 +745,12 @@ ctk_enable_option(Python_Wrapping "Wrap CTK classes using Qt meta-object system
                   CTK_LIB_Scripting/Python/Core)
 mark_as_superbuild(CTK_ENABLE_Python_Wrapping)
 
+include(CMakeDependentOption)
+cmake_dependent_option(
+  CTK_COMPILE_PYTHON_SCRIPT_SKIP_SCRIPT_COPY "Disable copy of .py files when using ctkMacroCompilePythonScript()" OFF
+  "CTK_ENABLE_Python_Wrapping" OFF)
+mark_as_superbuild(CTK_COMPILE_PYTHON_SCRIPT_SKIP_SCRIPT_COPY)
+
 # Build examples
 # Create the logical expression containing the minimum set of required options
 # for the CTK_BUILD_EXAMPLES option to be ON