Fix code review issues: NULL check, CMake syntax, and redundant config

- Add missing NULL check after PyDict_New() in run_simulation_with_params
- Fix CMake if() syntax: remove dollar-brace from variable references
- Remove redundant CFD_ROOT fallback in Windows cibuildwheel config
- Add dynamic version from setuptools-scm with fallbacks
- Add comment explaining Py_LIMITED_API build system requirement

Author: shaia

CMakeLists.txt

@@ -12,7 +12,7 @@ option(CFD_USE_STABLE_ABI "Use Python stable ABI (abi3)" OFF)
 find_package(Python 3.8 REQUIRED COMPONENTS Interpreter Development.Module)
 
 # Enable stable ABI (abi3) for Python 3.8+ if requested
-if(CFD_USE_STABLE_ABI AND ${Python_VERSION} VERSION_GREATER_EQUAL "3.8")
+if(CFD_USE_STABLE_ABI AND Python_VERSION VERSION_GREATER_EQUAL "3.8")
     set(CMAKE_C_VISIBILITY_PRESET hidden)
     set(CMAKE_CXX_VISIBILITY_PRESET hidden)
     add_definitions(-DPy_LIMITED_API=0x03080000)
@@ -84,7 +84,7 @@ set_target_properties(cfd_python PROPERTIES
 )
 
 # Use stable ABI if requested and available
-if(CFD_USE_STABLE_ABI AND ${Python_VERSION} VERSION_GREATER_EQUAL "3.8")
+if(CFD_USE_STABLE_ABI AND Python_VERSION VERSION_GREATER_EQUAL "3.8")
     target_compile_definitions(cfd_python PRIVATE Py_LIMITED_API=0x03080000)
 endif()
 

cfd_python/__init__.py

@@ -21,7 +21,17 @@
     - OUTPUT_CSV_STATISTICS: Global statistics (CSV)
 """
 
-__version__ = "0.3.0"
+# Get version from package metadata (setuptools-scm) or fall back to C module
+try:
+    from importlib.metadata import version, PackageNotFoundError
+    try:
+        __version__ = version("cfd-python")
+    except PackageNotFoundError:
+        # Package not installed, try C module version
+        __version__ = None
+except ImportError:
+    # Python < 3.8 fallback
+    __version__ = None
 
 # Core exports that are always available
 _CORE_EXPORTS = [
@@ -76,6 +86,10 @@
     # Import the C extension module to access dynamic solver constants
     from . import cfd_python as _cfd_module
 
+    # Fall back to C module version if metadata lookup failed
+    if __version__ is None:
+        __version__ = getattr(_cfd_module, '__version__', '0.0.0')
+
     # Dynamically export all SOLVER_* constants from the C module
     # This allows new solvers to be automatically available without
     # updating this file
@@ -90,4 +104,6 @@
 
 except ImportError:
     # Development mode - module not yet built
-    __all__ = _CORE_EXPORTS
+    __all__ = _CORE_EXPORTS
+    if __version__ is None:
+        __version__ = "0.0.0-dev"

pyproject.toml

@@ -104,9 +104,8 @@ environment = { CMAKE_BUILD_TYPE = "Release", CFD_STATIC_LINK = "ON", CFD_USE_ST
 [tool.cibuildwheel.windows]
 # Windows-specific configuration
 # Build CFD library first (static), then build Python extension
-# CFD_ROOT environment variable specifies the CFD library location (default: ../cfd)
+# CFD_ROOT is set in environment below
 before-build = [
-    "if not defined CFD_ROOT set CFD_ROOT=../cfd",
     "cd %CFD_ROOT% && cmake -B build -DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=OFF",
     "cd %CFD_ROOT% && cmake --build build --config Release",
 ]

src/cfd_python.c

@@ -1,3 +1,9 @@
+// Py_LIMITED_API should be defined via build system (CMake) before including Python.h
+// for stable ABI support. The CMake option CFD_USE_STABLE_ABI controls this.
+// When enabled, it targets Python 3.8+ stable ABI (0x03080000) for binary compatibility
+// across Python versions. Do NOT define it here unconditionally as it requires linking
+// against python3.lib which may not be available in all environments.
+
 #define PY_SSIZE_T_CLEAN
 #include <Python.h>
 #include <stdio.h>
@@ -375,6 +381,10 @@ static PyObject* run_simulation_with_params(PyObject* self, PyObject* args, PyOb
 
     // Create results dictionary
     PyObject* results = PyDict_New();
+    if (results == NULL) {
+        free_simulation(sim_data);
+        return NULL;
+    }
 
     // Get velocity magnitude
     FlowField* field = sim_data->field;