Refactor: simplify "_bpy_types" initialization internals

ideasman42 · ideasman42 · commit ce3998ffea39 · 2025-08-10T03:48:48.000Z
- Store the `_bpy_types` dictionary on startup instead of
  importing and setting on demand.

- Remove duplicate `_bpy_types` import.
diff --git a/source/blender/python/intern/bpy.cc b/source/blender/python/intern/bpy.cc
@@ -757,9 +757,21 @@ void BPy_init_modules(bContext *C)
 
   BPY_rna_gizmo_module(mod);
 
-  bpy_import_test("_bpy_types");
-  PyModule_AddObject(mod, "data", BPY_rna_module()); /* Imports `_bpy_types` by running this. */
-  bpy_import_test("_bpy_types");
+  /* Important to internalizes `_bpy_types` before creating RNA instances. */
+  {
+    /* Set a dummy module so the `_bpy_types.py` can access `bpy.types.ID`
+     * without a null pointer dereference when instancing types. */
+    PyObject *bpy_types_dict_dummy = PyDict_New();
+    BPY_rna_types_dict_set(bpy_types_dict_dummy);
+    PyObject *bpy_types_module_py = bpy_import_test("_bpy_types");
+    /* Something has gone wrong if this is ever populated. */
+    BLI_assert(PyDict_GET_SIZE(bpy_types_dict_dummy) == 0);
+    Py_DECREF(bpy_types_dict_dummy);
+
+    PyObject *bpy_types_module_py_dict = PyModule_GetDict(bpy_types_module_py);
+    BPY_rna_types_dict_set(bpy_types_module_py_dict);
+  }
+  PyModule_AddObject(mod, "data", BPY_rna_module());
   BPY_rna_types_finalize_external_types(bpy_types);
 
   PyModule_AddObject(mod, "props", BPY_rna_props());
diff --git a/source/blender/python/intern/bpy_rna.cc b/source/blender/python/intern/bpy_rna.cc
@@ -8130,7 +8130,7 @@ static void pyrna_subtype_set_rna(PyObject *newclass, StructRNA *srna)
 /**
  * \return borrowed reference.
  */
-static PyObject *pyrna_srna_PyBase(StructRNA *srna)  //, PyObject *bpy_types_dict)
+static PyObject *pyrna_srna_PyBase(StructRNA *srna)
 {
   /* Assume RNA_struct_py_type_get(srna) was already checked. */
   StructRNA *base;
@@ -8153,9 +8153,15 @@ static PyObject *pyrna_srna_PyBase(StructRNA *srna)  //, PyObject *bpy_types_dic
   return py_base;
 }
 
-/* Check if we have a native Python subclass, use it when it exists
- * return a borrowed reference. */
+/**
+ * Check if we have a native Python subclass, use it when it exists
+ * return a borrowed reference.
+ */
 static PyObject *bpy_types_dict = nullptr;
+void BPY_rna_types_dict_set(PyObject *dict)
+{
+  bpy_types_dict = dict; /* Borrow. */
+}
 
 /**
  * Return the #PyTypeObject or null,
@@ -8164,22 +8170,10 @@ static PyObject *bpy_types_dict = nullptr;
  */
 static PyObject *pyrna_srna_ExternalType(StructRNA *srna)
 {
-  const char *idname = RNA_struct_identifier(srna);
-  PyObject *newclass;
-
-  if (bpy_types_dict == nullptr) {
-    PyObject *bpy_types = PyImport_ImportModuleLevel("_bpy_types", nullptr, nullptr, nullptr, 0);
+  BLI_assert(bpy_types_dict);
 
-    if (bpy_types == nullptr) {
-      PyErr_Print();
-      CLOG_ERROR(BPY_LOG_RNA, "failed to find '_bpy_types' module");
-      return nullptr;
-    }
-    bpy_types_dict = PyModule_GetDict(bpy_types); /* Borrow. */
-    Py_DECREF(bpy_types);                         /* Fairly safe to assume the dict is kept. */
-  }
-
-  newclass = PyDict_GetItemString(bpy_types_dict, idname);
+  const char *idname = RNA_struct_identifier(srna);
+  PyObject *newclass = PyDict_GetItemString(bpy_types_dict, idname);
 
   /* Sanity check, could skip this unless in debug mode. */
   if (newclass) {
diff --git a/source/blender/python/intern/bpy_rna.hh b/source/blender/python/intern/bpy_rna.hh
@@ -203,6 +203,10 @@ void BPY_rna_exit();
 void BPY_update_rna_module();
 // PyObject *BPY_rna_doc();
 [[nodiscard]] PyObject *BPY_rna_types();
+/**
+ * Set the `_bpy_types.py` modules `__dict__`, needed for instancing RNA types.
+ */
+void BPY_rna_types_dict_set(PyObject *dict);
 void BPY_rna_types_finalize_external_types(PyObject *submodule);
 
 [[nodiscard]] PyObject *pyrna_struct_CreatePyObject_with_primitive_support(PointerRNA *ptr);
