diff options
| -rw-r--r-- | Lib/pickle.py | 40 | ||||
| -rw-r--r-- | Lib/test/pickletester.py | 12 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2024-07-23-09-14-44.gh-issue-82951.-F5p5A.rst | 3 | ||||
| -rw-r--r-- | Modules/_pickle.c | 53 |
4 files changed, 82 insertions, 26 deletions
diff --git a/Lib/pickle.py b/Lib/pickle.py index 115bd89..2d76498 100644 --- a/Lib/pickle.py +++ b/Lib/pickle.py @@ -1110,11 +1110,35 @@ class _Pickler: self.save(module_name) self.save(name) write(STACK_GLOBAL) - elif parent is not module: - self.save_reduce(getattr, (parent, lastname)) - elif self.proto >= 3: - write(GLOBAL + bytes(module_name, "utf-8") + b'\n' + - bytes(name, "utf-8") + b'\n') + elif '.' in name: + # In protocol < 4, objects with multi-part __qualname__ + # are represented as + # getattr(getattr(..., attrname1), attrname2). + dotted_path = name.split('.') + name = dotted_path.pop(0) + save = self.save + for attrname in dotted_path: + save(getattr) + if self.proto < 2: + write(MARK) + self._save_toplevel_by_name(module_name, name) + for attrname in dotted_path: + save(attrname) + if self.proto < 2: + write(TUPLE) + else: + write(TUPLE2) + write(REDUCE) + else: + self._save_toplevel_by_name(module_name, name) + + self.memoize(obj) + + def _save_toplevel_by_name(self, module_name, name): + if self.proto >= 3: + # Non-ASCII identifiers are supported only with protocols >= 3. + self.write(GLOBAL + bytes(module_name, "utf-8") + b'\n' + + bytes(name, "utf-8") + b'\n') else: if self.fix_imports: r_name_mapping = _compat_pickle.REVERSE_NAME_MAPPING @@ -1124,15 +1148,13 @@ class _Pickler: elif module_name in r_import_mapping: module_name = r_import_mapping[module_name] try: - write(GLOBAL + bytes(module_name, "ascii") + b'\n' + - bytes(name, "ascii") + b'\n') + self.write(GLOBAL + bytes(module_name, "ascii") + b'\n' + + bytes(name, "ascii") + b'\n') except UnicodeEncodeError: raise PicklingError( "can't pickle global identifier '%s.%s' using " "pickle protocol %i" % (module, name, self.proto)) from None - self.memoize(obj) - def save_type(self, obj): if obj is type(None): return self.save_reduce(type, (None,), obj=obj) diff --git a/Lib/test/pickletester.py b/Lib/test/pickletester.py index 9922591..1366322 100644 --- a/Lib/test/pickletester.py +++ b/Lib/test/pickletester.py @@ -2818,6 +2818,18 @@ class AbstractPickleTests: self.assertIs(unpickled, Recursive) del Recursive.mod # break reference loop + def test_recursive_nested_names2(self): + global Recursive + class Recursive: + pass + Recursive.ref = Recursive + Recursive.__qualname__ = 'Recursive.ref' + for proto in range(pickle.HIGHEST_PROTOCOL + 1): + with self.subTest(proto=proto): + unpickled = self.loads(self.dumps(Recursive, proto)) + self.assertIs(unpickled, Recursive) + del Recursive.ref # break reference loop + def test_py_methods(self): global PyMethodsTest class PyMethodsTest: diff --git a/Misc/NEWS.d/next/Library/2024-07-23-09-14-44.gh-issue-82951.-F5p5A.rst b/Misc/NEWS.d/next/Library/2024-07-23-09-14-44.gh-issue-82951.-F5p5A.rst new file mode 100644 index 0000000..b3f0788 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-07-23-09-14-44.gh-issue-82951.-F5p5A.rst @@ -0,0 +1,3 @@ +Serializing objects with complex ``__qualname__`` (such as unbound methods +and nested classes) by name no longer involves serializing parent objects by +value in pickle protocols < 4. diff --git a/Modules/_pickle.c b/Modules/_pickle.c index 7eebe92..861363b 100644 --- a/Modules/_pickle.c +++ b/Modules/_pickle.c @@ -3592,7 +3592,6 @@ save_global(PickleState *st, PicklerObject *self, PyObject *obj, PyObject *module = NULL; PyObject *parent = NULL; PyObject *dotted_path = NULL; - PyObject *lastname = NULL; PyObject *cls; int status = 0; @@ -3633,10 +3632,7 @@ save_global(PickleState *st, PicklerObject *self, PyObject *obj, obj, module_name); goto error; } - lastname = Py_NewRef(PyList_GET_ITEM(dotted_path, - PyList_GET_SIZE(dotted_path) - 1)); cls = get_deep_attribute(module, dotted_path, &parent); - Py_CLEAR(dotted_path); if (cls == NULL) { PyErr_Format(st->PicklingError, "Can't pickle %R: attribute lookup %S on %S failed", @@ -3724,7 +3720,10 @@ save_global(PickleState *st, PicklerObject *self, PyObject *obj, else { gen_global: if (parent == module) { - Py_SETREF(global_name, Py_NewRef(lastname)); + Py_SETREF(global_name, + Py_NewRef(PyList_GET_ITEM(dotted_path, + PyList_GET_SIZE(dotted_path) - 1))); + Py_CLEAR(dotted_path); } if (self->proto >= 4) { const char stack_global_op = STACK_GLOBAL; @@ -3737,20 +3736,30 @@ save_global(PickleState *st, PicklerObject *self, PyObject *obj, if (_Pickler_Write(self, &stack_global_op, 1) < 0) goto error; } - else if (parent != module) { - PyObject *reduce_value = Py_BuildValue("(O(OO))", - st->getattr, parent, lastname); - if (reduce_value == NULL) - goto error; - status = save_reduce(st, self, reduce_value, NULL); - Py_DECREF(reduce_value); - if (status < 0) - goto error; - } else { /* Generate a normal global opcode if we are using a pickle protocol < 4, or if the object is not registered in the - extension registry. */ + extension registry. + + Objects with multi-part __qualname__ are represented as + getattr(getattr(..., attrname1), attrname2). */ + const char mark_op = MARK; + const char tupletwo_op = (self->proto < 2) ? TUPLE : TUPLE2; + const char reduce_op = REDUCE; + Py_ssize_t i; + if (dotted_path) { + if (PyList_GET_SIZE(dotted_path) > 1) { + Py_SETREF(global_name, Py_NewRef(PyList_GET_ITEM(dotted_path, 0))); + } + for (i = 1; i < PyList_GET_SIZE(dotted_path); i++) { + if (save(st, self, st->getattr, 0) < 0 || + (self->proto < 2 && _Pickler_Write(self, &mark_op, 1) < 0)) + { + goto error; + } + } + } + PyObject *encoded; PyObject *(*unicode_encoder)(PyObject *); @@ -3812,6 +3821,17 @@ save_global(PickleState *st, PicklerObject *self, PyObject *obj, Py_DECREF(encoded); if (_Pickler_Write(self, "\n", 1) < 0) goto error; + + if (dotted_path) { + for (i = 1; i < PyList_GET_SIZE(dotted_path); i++) { + if (save(st, self, PyList_GET_ITEM(dotted_path, i), 0) < 0 || + _Pickler_Write(self, &tupletwo_op, 1) < 0 || + _Pickler_Write(self, &reduce_op, 1) < 0) + { + goto error; + } + } + } } /* Memoize the object. */ if (memo_put(st, self, obj) < 0) @@ -3827,7 +3847,6 @@ save_global(PickleState *st, PicklerObject *self, PyObject *obj, Py_XDECREF(module); Py_XDECREF(parent); Py_XDECREF(dotted_path); - Py_XDECREF(lastname); return status; } |