fix(tests): Fix exception on copying frame.f_locals (Python 3.13) (#3271)

Starting from Python 3.13, `frame.f_locals` is not `dict` anymore, but
`FrameLocalsProxy`, that cannot be copied using `copy.copy()`. In Python
3.13 and later, it should be copied using a method `.copy()`. The new way
of copying works the same as the old one for versions of Python prior to
3.13, according to the documentation (both copying methods produce a
shallow copy).

Since Python 3.13, `FrameLocalsProxy` skips items of `locals()` that have
non-`str` keys; this is a CPython implementation detail, so we hence
disable `test_non_string_variables` test on Python 3.13.

See:
https://peps.python.org/pep-0667/
python/cpython#118921
python/cpython#118923
https://docs.python.org/3.13/whatsnew/3.13.html#porting-to-python-3-13
https://docs.python.org/3/library/copy.html
https://github.com/python/cpython/blame/7b413952e817ae87bfda2ac85dd84d30a6ce743b/Objects/frameobject.c#L148

Author: rominf

sentry_sdk/utils.py

@@ -11,7 +11,6 @@
 import threading
 import time
 from collections import namedtuple
-from copy import copy
 from datetime import datetime
 from decimal import Decimal
 from functools import partial, partialmethod, wraps
@@ -618,7 +617,7 @@ def serialize_frame(
         )
 
     if include_local_variables:
-        rv["vars"] = copy(frame.f_locals)
+        rv["vars"] = frame.f_locals.copy()
 
     return rv
 

tests/test_client.py

@@ -31,6 +31,12 @@
     from sentry_sdk._types import Event
 
 
+maximum_python_312 = pytest.mark.skipif(
+    sys.version_info > (3, 12),
+    reason="Since Python 3.13, `FrameLocalsProxy` skips items of `locals()` that have non-`str` keys; this is a CPython implementation detail: https://github.com/python/cpython/blame/7b413952e817ae87bfda2ac85dd84d30a6ce743b/Objects/frameobject.c#L148",
+)
+
+
 class EnvelopeCapturedError(Exception):
     pass
 
@@ -879,6 +885,7 @@ class FooError(Exception):
     assert exception["mechanism"]["meta"]["errno"]["number"] == 69
 
 
+@maximum_python_312
 def test_non_string_variables(sentry_init, capture_events):
     """There is some extremely terrible code in the wild that
     inserts non-strings as variable names into `locals()`."""