Add _PyModule_IsInitializing().

Author: serhiy-storchaka

Include/moduleobject.h

@@ -30,6 +30,7 @@ PyAPI_FUNC(PyObject *) PyModule_GetFilenameObject(PyObject *);
 #ifndef Py_LIMITED_API
 PyAPI_FUNC(void) _PyModule_Clear(PyObject *);
 PyAPI_FUNC(void) _PyModule_ClearDict(PyObject *);
+PyAPI_FUNC(int) _PyModule_IsInitializing(PyObject *);
 #endif
 PyAPI_FUNC(struct PyModuleDef*) PyModule_GetDef(PyObject*);
 PyAPI_FUNC(void*) PyModule_GetState(PyObject*);

Objects/moduleobject.c

@@ -699,6 +699,33 @@ module_repr(PyModuleObject *m)
     return PyObject_CallMethod(interp->importlib, "_module_repr", "O", m);
 }
 
+int
+_PyModule_IsInitializing(PyObject *m)
+{
+    if (PyModule_Check(m) && ((PyModuleObject *)m)->md_dict) {
+        _Py_IDENTIFIER(__spec__);
+        _Py_IDENTIFIER(_initializing);
+        PyObject *value = NULL;
+        PyObject *spec;
+        int initializing = 0;
+        spec = _PyDict_GetItemId(((PyModuleObject *)m)->md_dict, &PyId___spec__);
+        if (spec != NULL && spec != Py_None) {
+            value = _PyObject_GetAttrId(spec, &PyId__initializing);
+        }
+        if (value == NULL) {
+            PyErr_Clear();
+        }
+        else {
+            initializing = PyObject_IsTrue(value);
+            Py_DECREF(value);
+            if (initializing < 0)
+                PyErr_Clear();
+            return initializing > 0;
+        }
+    }
+    return 0;
+}
+
 static PyObject*
 module_getattro(PyModuleObject *m, PyObject *name)
 {
@@ -718,25 +745,8 @@ module_getattro(PyModuleObject *m, PyObject *name)
         _Py_IDENTIFIER(__name__);
         mod_name = _PyDict_GetItemId(m->md_dict, &PyId___name__);
         if (mod_name && PyUnicode_Check(mod_name)) {
-            _Py_IDENTIFIER(__spec__);
-            _Py_IDENTIFIER(_initializing);
-            PyObject *value = NULL;
-            PyObject *spec;
-            int initializing = 0;
             Py_INCREF(mod_name);
-            spec = _PyDict_GetItemId(m->md_dict, &PyId___spec__);
-            if (spec != NULL && spec != Py_None) {
-                value = _PyObject_GetAttrId(spec, &PyId__initializing);
-            }
-            if (value == NULL)
-                PyErr_Clear();
-            else {
-                initializing = PyObject_IsTrue(value);
-                Py_DECREF(value);
-                if (initializing < 0)
-                    PyErr_Clear();
-            }
-            if (initializing > 0) {
+            if (_PyModule_IsInitializing((PyObject *)m)) {
                 PyErr_Format(PyExc_AttributeError,
                              "partially initialized "
                              "module '%U' has no attribute '%U' "

Python/import.c

@@ -1720,38 +1720,20 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *globals,
 
     mod = PyImport_GetModule(abs_name);
     if (mod != NULL && mod != Py_None) {
-        _Py_IDENTIFIER(__spec__);
-        _Py_IDENTIFIER(_initializing);
         _Py_IDENTIFIER(_lock_unlock_module);
-        PyObject *value = NULL;
-        PyObject *spec;
-        int initializing = 0;
 
         /* Optimization: only call _bootstrap._lock_unlock_module() if
            __spec__._initializing is true.
            NOTE: because of this, initializing must be set *before*
            stuffing the new module in sys.modules.
          */
-        spec = _PyObject_GetAttrId(mod, &PyId___spec__);
-        if (spec != NULL) {
-            value = _PyObject_GetAttrId(spec, &PyId__initializing);
-            Py_DECREF(spec);
-        }
-        if (value == NULL)
-            PyErr_Clear();
-        else {
-            initializing = PyObject_IsTrue(value);
+        if (_PyModule_IsInitializing(mod)) {
+            PyObject *value = _PyObject_CallMethodIdObjArgs(interp->importlib,
+                                            &PyId__lock_unlock_module, abs_name,
+                                            NULL);
+            if (value == NULL)
+                goto error;
             Py_DECREF(value);
-            if (initializing == -1)
-                PyErr_Clear();
-            if (initializing > 0) {
-                value = _PyObject_CallMethodIdObjArgs(interp->importlib,
-                                                &PyId__lock_unlock_module, abs_name,
-                                                NULL);
-                if (value == NULL)
-                    goto error;
-                Py_DECREF(value);
-            }
         }
     }
     else {