bpo-40566: Apply PEP 573 to abc module

Misc/NEWS.d/next/Core and Builtins/2020-05-09-01-39-16.bpo-40566.wlcjW_.rst

@@ -0,0 +1 @@
+Apply :pep:`573` to :mod:`abc`.

Modules/_abc.c

@@ -21,16 +21,9 @@ _Py_IDENTIFIER(__subclasshook__);
 
 typedef struct {
  PyTypeObject *_abc_data_type;
+ unsigned long long abc_invalidation_counter;
 } _abcmodule_state;
 
-/* A global counter that is incremented each time a class is
- registered as a virtual subclass of anything. It forces the
- negative cache to be cleared before its next use.
- Note: this counter is private. Use `abc.get_cache_token()` for
- external code. */
-// FIXME: PEP 573: Move abc_invalidation_counter into _abcmodule_state.
-static unsigned long long abc_invalidation_counter = 0;
-
 static inline _abcmodule_state*
 get_abc_state(PyObject *module)
 {
@@ -81,14 +74,15 @@ static PyObject *
 abc_data_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 {
  _abc_data *self = (_abc_data *) type->tp_alloc(type, 0);
- if (self == NULL) {
+ _abcmodule_state *state = PyType_GetModuleState(type);
+ if (self == NULL || state == NULL) {
  return NULL;
  }
 
  self->_abc_registry = NULL;
  self->_abc_cache = NULL;
  self->_abc_negative_cache = NULL;
- self->_abc_negative_cache_version = abc_invalidation_counter;
+ self->_abc_negative_cache_version = state->abc_invalidation_counter;
  return (PyObject *) self;
 }
 
@@ -495,7 +489,7 @@ _abc__abc_register_impl(PyObject *module, PyObject *self, PyObject *subclass)
  Py_DECREF(impl);
 
  /* Invalidate negative cache */
- abc_invalidation_counter++;
+ get_abc_state(module)->abc_invalidation_counter++;
 
  Py_INCREF(subclass);
  return subclass;
@@ -540,7 +534,7 @@ _abc__abc_instancecheck_impl(PyObject *module, PyObject *self,
  }
  subtype = (PyObject *)Py_TYPE(instance);
  if (subtype == subclass) {
- if (impl->_abc_negative_cache_version == abc_invalidation_counter) {
+ if (impl->_abc_negative_cache_version == get_abc_state(module)->abc_invalidation_counter) {
  incache = _in_weak_set(impl->_abc_negative_cache, subclass);
  if (incache < 0) {
  goto end;
@@ -612,6 +606,7 @@ _abc__abc_subclasscheck_impl(PyObject *module, PyObject *self,
  }
 
  PyObject *ok, *subclasses = NULL, *result = NULL;
+ _abcmodule_state *state = NULL;
  Py_ssize_t pos;
  int incache;
  _abc_data *impl = _get_impl(module, self);
@@ -629,15 +624,16 @@ _abc__abc_subclasscheck_impl(PyObject *module, PyObject *self,
  goto end;
  }
 
+ state = get_abc_state(module);
  /* 2. Check negative cache; may have to invalidate. */
- if (impl->_abc_negative_cache_version < abc_invalidation_counter) {
+ if (impl->_abc_negative_cache_version < state->abc_invalidation_counter) {
  /* Invalidate the negative cache. */
  if (impl->_abc_negative_cache != NULL &&
  PySet_Clear(impl->_abc_negative_cache) < 0)
  {
  goto end;
  }
- impl->_abc_negative_cache_version = abc_invalidation_counter;
+ impl->_abc_negative_cache_version = state->abc_invalidation_counter;
  }
  else {
  incache = _in_weak_set(impl->_abc_negative_cache, subclass);
@@ -830,7 +826,8 @@ static PyObject *
 _abc_get_cache_token_impl(PyObject *module)
 /*[clinic end generated code: output=c7d87841e033dacc input=70413d1c423ad9f9]*/
 {
- return PyLong_FromUnsignedLongLong(abc_invalidation_counter);
+ _abcmodule_state *state = get_abc_state(module);
+ return PyLong_FromUnsignedLongLong(state->abc_invalidation_counter);
 }
 
 static struct PyMethodDef _abcmodule_methods[] = {
@@ -849,7 +846,8 @@ static int
 _abcmodule_exec(PyObject *module)
 {
  _abcmodule_state *state = get_abc_state(module);
- state->_abc_data_type = (PyTypeObject *)PyType_FromSpec(&_abc_data_type_spec);
+ state->abc_invalidation_counter = 0;
+ state->_abc_data_type = (PyTypeObject *)PyType_FromModuleAndSpec(module, &_abc_data_type_spec, NULL);
  if (state->_abc_data_type == NULL) {
  return -1;
  }