BUG: Condition building python stubs on python wrapping

Only build the python stub files if python is being wrapped.

Provide conditionals so that the python artifacts are only generated
when python wrapping is requested.

Author: hjmjohnson

Wrapping/Generators/SwigInterface/CMakeLists.txt

@@ -315,9 +315,14 @@ macro(itk_end_wrap_module_swig_interface)
   set(mdx_file "${WRAPPER_MASTER_INDEX_OUTPUT_DIR}/${WRAPPER_LIBRARY_NAME}.mdx")
   set(module_interface_file "${WRAPPER_MASTER_INDEX_OUTPUT_DIR}/${WRAPPER_LIBRARY_NAME}.i")
   set(module_interface_ext_file "${WRAPPER_MASTER_INDEX_OUTPUT_DIR}/${WRAPPER_LIBRARY_NAME}_ext.i")
-  set(ITK_STUB_DIR "${ITK_DIR}/Wrapping/Generators/Python/itk-stubs")
 
-  set(ITK_STUB_PYI_FILES )
+  if(${module_prefix}_WRAP_PYTHON)
+    set(ITK_STUB_DIR "${ITK_DIR}/Wrapping/Generators/Python/itk-stubs")
+    set(ITK_STUB_PYI_FILES)
+  else()
+    unset(ITK_STUB_DIR)
+    unset(ITK_STUB_PYI_FILES)
+  endif()
 
   foreach(module ${SWIG_INTERFACE_MODULES})
     # create the swig interface
@@ -326,7 +331,9 @@ macro(itk_end_wrap_module_swig_interface)
     list(APPEND idx_files "${WRAPPER_MASTER_INDEX_OUTPUT_DIR}/${module}.idx")
     list(APPEND typedef_in_files "${WRAPPER_LIBRARY_OUTPUT_DIR}/${module}SwigInterface.h.in")
     list(APPEND typedef_files "${WRAPPER_MASTER_INDEX_OUTPUT_DIR}/${module}SwigInterface.h")
-    list(APPEND ITK_STUB_PYI_FILES "${ITK_STUB_DIR}/${module}.pyi")
+    if(${module_prefix}_WRAP_PYTHON)
+      list(APPEND ITK_STUB_PYI_FILES "${ITK_STUB_DIR}/${module}.pyi")
+    endif()
 
 
     if(${module_prefix}_WRAP_EXPLICIT)
@@ -354,7 +361,10 @@ macro(itk_end_wrap_module_swig_interface)
 
   list(LENGTH i_files number_interface_files)
   if(number_interface_files GREATER 0)
+
       if(${module_prefix}_WRAP_PYTHON)
+        set(ITK_STUB_DIR "${ITK_DIR}/Wrapping/Generators/Python/itk-stubs")
+        set(ITK_STUB_PYI_FILE "${ITK_STUB_DIR}/${WRAPPER_LIBRARY_NAME}.pyi")
         # NOTE:  snake_case_config_file is both an input and an output to this command.
         #        the ${IGENERATOR} script appends to this file.
         # NOTE: The Configuration files should be placed in the itk package directory.
@@ -363,28 +373,46 @@ macro(itk_end_wrap_module_swig_interface)
         )
         set(snake_case_config_file
             "${ITK_WRAP_PYTHON_SNAKE_CONFIG_DIR}/${WRAPPER_LIBRARY_NAME}_snake_case.py")
+        add_custom_command(
+        OUTPUT ${i_files} ${typedef_files} ${idx_files} ${snake_case_config_file} ${ITK_STUB_PYI_FILES}
+        COMMAND ${Python3_EXECUTABLE} ${IGENERATOR}
+          ${mdx_opts}
+          ${swig_libs}
+          -w1 -w3 -w51 -w52 -w53 -w54
+          -A protected -A private
+          -p ${PYGCCXML_DIR}
+          -g ${CASTXML_EXECUTABLE}
+          --snake-case-file "${snake_case_config_file}"
+          --interface-output-dir "${WRAPPER_MASTER_INDEX_OUTPUT_DIR}"
+          --library-output-dir "${WRAPPER_LIBRARY_OUTPUT_DIR}"
+          --submodule-order "${WRAPPER_SUBMODULE_ORDER}"
+          --pyi_dir "${ITK_STUB_DIR}"
+          DEPENDS ${ITK_WRAP_DOC_DOCSTRING_FILES} ${xml_files} ${IGENERATOR} ${typedef_in_files}
+          WORKING_DIRECTORY / # Arguments to WORKING_DIRECTORY may use generator expressions
+        VERBATIM
+      )
       else()
+        unset(ITK_STUB_DIR)
+        unset(ITK_STUB_PYI_FILE)
         unset(snake_case_config_file)
+        add_custom_command(
+          OUTPUT ${i_files} ${typedef_files} ${idx_files}
+          COMMAND ${Python3_EXECUTABLE} ${IGENERATOR}
+            ${mdx_opts}
+            ${swig_libs}
+            -w1 -w3 -w51 -w52 -w53 -w54
+            -A protected -A private
+            -p ${PYGCCXML_DIR}
+            -g ${CASTXML_EXECUTABLE}
+            --interface-output-dir "${WRAPPER_MASTER_INDEX_OUTPUT_DIR}"
+            --library-output-dir "${WRAPPER_LIBRARY_OUTPUT_DIR}"
+            --submodule-order "${WRAPPER_SUBMODULE_ORDER}"
+            DEPENDS ${ITK_WRAP_DOC_DOCSTRING_FILES} ${xml_files} ${IGENERATOR} ${typedef_in_files}
+            WORKING_DIRECTORY / # Arguments to WORKING_DIRECTORY may use generator expressions
+          VERBATIM
+        )
       endif()
 
-      add_custom_command(
-      OUTPUT ${i_files} ${typedef_files} ${idx_files} ${snake_case_config_file} ${ITK_STUB_PYI_FILES}
-      COMMAND ${Python3_EXECUTABLE} ${IGENERATOR}
-        ${mdx_opts}
-        ${swig_libs}
-        -w1 -w3 -w51 -w52 -w53 -w54
-        -A protected -A private
-        -p ${PYGCCXML_DIR}
-        -g ${CASTXML_EXECUTABLE}
-        --snake-case-file "${snake_case_config_file}"
-        --interface-output-dir "${WRAPPER_MASTER_INDEX_OUTPUT_DIR}"
-        --library-output-dir "${WRAPPER_LIBRARY_OUTPUT_DIR}"
-        --submodule-order "${WRAPPER_SUBMODULE_ORDER}"
-        --pyi_dir "${ITK_STUB_DIR}"
-        DEPENDS ${ITK_WRAP_DOC_DOCSTRING_FILES} ${xml_files} ${IGENERATOR} ${typedef_in_files}
-        WORKING_DIRECTORY / # Arguments to WORKING_DIRECTORY may use generator expressions
-      VERBATIM
-    )
   endif()
 
   # the ${WRAPPER_LIBRARY_NAME}Swig target

Wrapping/Generators/SwigInterface/igenerator.py

@@ -1906,13 +1906,16 @@ def write_common_init_interface_file(interface_dir_path: Path) -> None:
         "--pyi_dir",
         action="store",
         dest="pyi_dir",
+        default="",
+        type=str,
         help="The directory for .pyi files to be generated",
     )
 
     options = argParser.parse_args()
 
     # Ensure that the requested stub file directory exists
-    Path(f"{options.pyi_dir}").mkdir(exist_ok=True, parents=True)
+    if options.pyi_dir != "":
+        Path(options.pyi_dir).mkdir(exist_ok=True, parents=True)
 
     sys.path.insert(1, options.pygccxml_path)
     import pygccxml
@@ -2007,11 +2010,13 @@ def generate_swig_input(submoduleName, classes):
 
     for submoduleName in ordered_submodule_list:
         generate_swig_input(submoduleName, classes)
-        init_submodule_pyi_file(
+        if options.pyi_dir != "":
+          init_submodule_pyi_file(
             Path(f"{options.pyi_dir}/{submoduleName}.pyi"), submoduleName
-        )
+          )
 
-    for itk_class in classes.keys():
+    if options.pyi_dir != "":
+      for itk_class in classes.keys():
         outputPYIHeaderFile = StringIO()
         outputPYIMethodFile = StringIO()
         generate_class_pyi_def(
@@ -2025,7 +2030,6 @@ def generate_swig_input(submoduleName, classes):
             outputPYIMethodFile.getvalue(),
         )
 
-        write_common_init_interface_file(Path(options.pyi_dir))
 
     snake_case_file = options.snake_case_file
     if len(snake_case_file) > 1: