Add _PyType_GetModuleByDef (GH-22835)
See https://mail.python.org/archives/list/capi-sig@python.org/thread/T3P2QNLNLBRFHWSKYSTPMVEIL2EEKFJU/ for discussion.
https://bugs.python.org/issue42100
diff --git a/Include/cpython/object.h b/Include/cpython/object.h
index 875a600..0db53c3 100644
--- a/Include/cpython/object.h
+++ b/Include/cpython/object.h
@@ -296,6 +296,8 @@ PyAPI_FUNC(PyObject *) _PyObject_LookupSpecial(PyObject *, _Py_Identifier *);
PyAPI_FUNC(PyTypeObject *) _PyType_CalculateMetaclass(PyTypeObject *, PyObject *);
PyAPI_FUNC(PyObject *) _PyType_GetDocFromInternalDoc(const char *, const char *);
PyAPI_FUNC(PyObject *) _PyType_GetTextSignatureFromInternalDoc(const char *, const char *);
+struct PyModuleDef;
+PyAPI_FUNC(PyObject *) _PyType_GetModuleByDef(PyTypeObject *, struct PyModuleDef *);
struct _Py_Identifier;
PyAPI_FUNC(int) PyObject_Print(PyObject *, FILE *, int);
diff --git a/Modules/_testmultiphase.c b/Modules/_testmultiphase.c
index 8bba077..ad60f32 100644
--- a/Modules/_testmultiphase.c
+++ b/Modules/_testmultiphase.c
@@ -121,24 +121,30 @@ static PyType_Spec Example_Type_spec = {
};
+static PyModuleDef def_meth_state_access;
+
/*[clinic input]
_testmultiphase.StateAccessType.get_defining_module
cls: defining_class
Return the module of the defining class.
+
+Also tests that result of _PyType_GetModuleByDef matches defining_class's
+module.
[clinic start generated code]*/
static PyObject *
_testmultiphase_StateAccessType_get_defining_module_impl(StateAccessTypeObject *self,
PyTypeObject *cls)
-/*[clinic end generated code: output=ba2a14284a5d0921 input=946149f91cf72c0d]*/
+/*[clinic end generated code: output=ba2a14284a5d0921 input=356f999fc16e0933]*/
{
PyObject *retval;
retval = PyType_GetModule(cls);
if (retval == NULL) {
return NULL;
}
+ assert(_PyType_GetModuleByDef(Py_TYPE(self), &def_meth_state_access) == retval);
Py_INCREF(retval);
return retval;
}
diff --git a/Modules/clinic/_testmultiphase.c.h b/Modules/clinic/_testmultiphase.c.h
index 0d38c23..55f934b 100644
--- a/Modules/clinic/_testmultiphase.c.h
+++ b/Modules/clinic/_testmultiphase.c.h
@@ -6,7 +6,10 @@ PyDoc_STRVAR(_testmultiphase_StateAccessType_get_defining_module__doc__,
"get_defining_module($self, /)\n"
"--\n"
"\n"
-"Return the module of the defining class.");
+"Return the module of the defining class.\n"
+"\n"
+"Also tests that result of _PyType_GetModuleByDef matches defining_class\'s\n"
+"module.");
#define _TESTMULTIPHASE_STATEACCESSTYPE_GET_DEFINING_MODULE_METHODDEF \
{"get_defining_module", (PyCFunction)(void(*)(void))_testmultiphase_StateAccessType_get_defining_module, METH_METHOD|METH_FASTCALL|METH_KEYWORDS, _testmultiphase_StateAccessType_get_defining_module__doc__},
@@ -98,4 +101,4 @@ _testmultiphase_StateAccessType_get_count(StateAccessTypeObject *self, PyTypeObj
exit:
return return_value;
}
-/*[clinic end generated code: output=39eea487e94e7f5d input=a9049054013a1b77]*/
+/*[clinic end generated code: output=f01137bb3b373e14 input=a9049054013a1b77]*/
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index bd1587a..2daf374 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -3158,6 +3158,44 @@ PyType_GetModuleState(PyTypeObject *type)
return PyModule_GetState(m);
}
+
+/* Get the module of the first superclass where the module has the
+ * given PyModuleDef.
+ * Implemented by walking the MRO, is relatively slow.
+ *
+ * This is internal API for experimentation within stdlib. Discussion:
+ * https://mail.python.org/archives/list/capi-sig@python.org/thread/T3P2QNLNLBRFHWSKYSTPMVEIL2EEKFJU/
+ */
+PyObject *
+_PyType_GetModuleByDef(PyTypeObject *type, struct PyModuleDef *def)
+{
+ assert(PyType_Check(type));
+ assert(type->tp_mro);
+ int i;
+ for (i = 0; i < PyTuple_GET_SIZE(type->tp_mro); i++) {
+ PyObject *super = PyTuple_GET_ITEM(type->tp_mro, i);
+ if (!PyType_HasFeature((PyTypeObject *)super, Py_TPFLAGS_HEAPTYPE)) {
+ /* Currently, there's no way for static types to inherit
+ * from heap types, but to allow that possibility,
+ * we `continue` rather than `break`.
+ * We'll just potentially loop a few more times before throwing
+ * the error.
+ */
+ continue;
+ }
+ PyHeapTypeObject *ht = (PyHeapTypeObject*)super;
+ if (ht->ht_module && PyModule_GetDef(ht->ht_module) == def) {
+ return ht->ht_module;
+ }
+ }
+ PyErr_Format(
+ PyExc_TypeError,
+ "_PyType_GetModuleByDef: No superclass of '%s' has the given module",
+ type->tp_name);
+ return NULL;
+}
+
+
/* Internal API to look for a name through the MRO, bypassing the method cache.
This returns a borrowed reference, and might set an exception.
'error' is set to: -1: error with exception; 1: error without exception; 0: ok */