cmake: fix issue #25048 have cmake fail when pivy and swig use different API versions, update status messages

cMake/FreeCAD_Helpers/SetupSwig.cmake

@@ -1,12 +1,160 @@
 macro(SetupSwig)
+
 #-------------------------------- Swig ----------------------------------
 
-    find_package(SWIG)
+# force cmake to re-search for SWIG when CMAKE_PREFIX_PATH changes
+unset(SWIG_EXECUTABLE CACHE)
+unset(SWIG_DIR CACHE)
+unset(SWIG_VERSION CACHE)
+unset(SWIG_FOUND CACHE)
+
+if(BUILD_SKETCHER)
+    # SWIG is required for sketcher WB (use QUIET to provide custom error message)
+    find_package(SWIG QUIET)
 
     if(NOT SWIG_FOUND)
-        message("=====================================================\n"
+        message(FATAL_ERROR
-                "SWIG not found, will not build SWIG binding for pivy.\n"
+                "-----------------------------------------------------\n"
-                "=====================================================\n")
+                "SWIG not found, swig & pivy required for sketcher WB.\n"
-    endif(NOT SWIG_FOUND)
+                "-----------------------------------------------------\n")
+        # do not continue with check if swig not found
+        return()
+    endif()
 
-endmacro(SetupSwig)
+    # check swig/pivy runtime compatibility
+    message(STATUS "checking SWIG/Pivy runtime compatibility...")
+
+    # get SWIG's runtime version using -external-runtime flag
+    execute_process(
+        COMMAND ${SWIG_EXECUTABLE} -python -external-runtime "${CMAKE_BINARY_DIR}/swig_runtime_check.h"
+        RESULT_VARIABLE SWIG_EXTERNAL_RUNTIME_RESULT
+        ERROR_VARIABLE SWIG_EXTERNAL_RUNTIME_ERROR
+        ERROR_QUIET
+    )
+    # NOTE: only print the below output if using `cmake --log-level=DEBUG`
+    message(DEBUG "SWIG external-runtime result: ${SWIG_EXTERNAL_RUNTIME_RESULT}")
+    message(DEBUG "SWIG external-runtime error: ${SWIG_EXTERNAL_RUNTIME_ERROR}")
+
+    message(STATUS "Looking for: ${CMAKE_BINARY_DIR}/swig_runtime_check.h")
+    if(EXISTS "${CMAKE_BINARY_DIR}/swig_runtime_check.h")
+        message(STATUS "File exists: YES")
+    else()
+        message(STATUS "File exists: NO")
+    endif()
+
+    if(EXISTS "${CMAKE_BINARY_DIR}/swig_runtime_check.h")
+        file(STRINGS "${CMAKE_BINARY_DIR}/swig_runtime_check.h"
+            SWIG_RUNTIME_VERSION_LINE
+            REGEX "^#define SWIG_RUNTIME_VERSION")
+
+        message(STATUS "SWIG_RUNTIME_VERSION_LINE: ${SWIG_RUNTIME_VERSION_LINE}")
+
+        if(SWIG_RUNTIME_VERSION_LINE)
+            # extract the version number (it's in quotes: "5")
+            string(REGEX MATCH "\"([0-9]+)\"" _ "${SWIG_RUNTIME_VERSION_LINE}")
+            set(SWIG_RUNTIME_VERSION "${CMAKE_MATCH_1}")
+            message(STATUS "Extracted SWIG_RUNTIME_VERSION: ${SWIG_RUNTIME_VERSION}")
+        endif()
+
+        file(REMOVE "${CMAKE_BINARY_DIR}/swig_runtime_check.h")
+    else()
+        message(STATUS "swig_runtime_check.h not found!")
+    endif()
+
+    # extract pivy's SWIG runtime version from the compiled module
+    # NOTE: python code can not be indented
+    set(PYTHON_CHECK_PIVY_RUNTIME [=[
+import sys
+import os
+import re
+
+try:
+    import pivy
+    pivy_dir = os.path.dirname(pivy.__file__)
+    print(f'DEBUG:pivy_dir={pivy_dir}', file=sys.stderr)
+    print(f'DEBUG:files={os.listdir(pivy_dir)}', file=sys.stderr)
+
+    pivy_path = None
+
+    # Look for _coin module with any extension (.so on Unix, .pyd on Windows)
+    for f in os.listdir(pivy_dir):
+        print(f'DEBUG:checking={f}', file=sys.stderr)
+        if f.startswith('_coin') and (f.endswith('.so') or f.endswith('.pyd')):
+            pivy_path = os.path.join(pivy_dir, f)
+            break
+
+    print(f'DEBUG:pivy_path={pivy_path}', file=sys.stderr)
+
+    if pivy_path and os.path.exists(pivy_path):
+        with open(pivy_path, 'rb') as f:
+            content = f.read().decode('latin-1', errors='ignore')
+
+        print(f'DEBUG:content_len={len(content)}', file=sys.stderr)
+
+        # Use regex to find swig_runtime_data followed by a number
+        match = re.search(r'swig_runtime_data(\d+)', content)
+        print(f'DEBUG:match={match}', file=sys.stderr)
+        if match:
+            print(match.group(1))
+
+except ImportError as e:
+    print(f'DEBUG:import_error={e}', file=sys.stderr)
+    print('ERROR_IMPORT')
+except Exception as e:
+    print(f'DEBUG:exception={e}', file=sys.stderr)
+]=])
+
+execute_process(
+    COMMAND ${Python3_EXECUTABLE} -c "${PYTHON_CHECK_PIVY_RUNTIME}"
+    OUTPUT_VARIABLE PIVY_RUNTIME_VERSION
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+    ERROR_VARIABLE PIVY_DEBUG_OUTPUT
+    TIMEOUT 10
+)
+
+message(DEBUG "Pivy debug output: ${PIVY_DEBUG_OUTPUT}")
+
+    # Handle errors and compare versions
+    if(PIVY_RUNTIME_VERSION STREQUAL "ERROR_IMPORT")
+        message(WARNING
+            "Could not import pivy to check SWIG compatibility.\n"
+            "Proceeding without SWIG version check."
+        )
+    elseif(SWIG_RUNTIME_VERSION AND PIVY_RUNTIME_VERSION)
+        if(NOT SWIG_RUNTIME_VERSION STREQUAL PIVY_RUNTIME_VERSION)
+            message(FATAL_ERROR
+" --------------------------------------------------------
+ 
+ SWIG / PIVY RUNTIME VERSION MISMATCH DETECTED!
+ 
+ SWIG runtime API version: ${SWIG_RUNTIME_VERSION}
+ Pivy runtime API version: ${PIVY_RUNTIME_VERSION}
+  
+ These must match for compatibility.
+ This will cause runtime errors: 'No SWIG wrapped library loaded'
+  
+ swig v4.4.x is not compatible with pivy built with swig <=4.3.x
+  
+ FIX: Install a SWIG version that uses runtime ${PIVY_RUNTIME_VERSION}
+ or rebuild Pivy with your current SWIG ${SWIG_VERSION}.
+ 
+--------------------------------------------------------"
+            )
+        else()
+            message(STATUS "SWIG/Pivy runtime compatibility: PASSED")
+            message(STATUS "swig runtime API version: ${SWIG_RUNTIME_VERSION}")
+            message(STATUS "pivy runtime API version: ${PIVY_RUNTIME_VERSION}")
+            message(STATUS "swig binary version building freecad: ${SWIG_VERSION}")
+        endif()
+    else()
+        if(NOT SWIG_RUNTIME_VERSION)
+            message(WARNING "Could not determine SWIG runtime version")
+        endif()
+        if(NOT PIVY_RUNTIME_VERSION)
+            message(WARNING "Could not determine Pivy runtime version")
+        endif()
+        message(WARNING "Proceeding without SWIG/Pivy compatibility check.")
+    endif()
+endif()
+
+endmacro()