[issue35108] inspect.getmembers passes exceptions from object's properties through

[Karthikeyan Singaravelan]

Karthikeyan Singaravelan <tir.karthi at gmail.com> added the comment:

There are some relevant docs in the inspect module about properties triggering code execution and thus using getattr_static to fetch attributes. Ref : https://docs.python.org/3/library/inspect.html#fetching-attributes-statically . I tried the below and it passes for your code but there might be still cases where getattr_static triggers an exception too where we need to decide whether to skip the attribute from being listed and if so with a test for the scenario.

Using getattr_static first causes test_inspect.TestPredicates.test_get_slot_members to fail by including slot_member. Thus we try for getattr and if it raises an exception that is not AttributeError (@property might also raise AttributeError consciously at runtime) and then use getattr_static in case of exception other than AttributeError. This helps in passing the test suite and also the example attached listing bar which raises NotImplementedError or other Exceptions.


diff --git a/Lib/inspect.py b/Lib/inspect.py
index b8a142232b..9df2173e0c 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -341,7 +341,12 @@ def getmembers(object, predicate=None):
         # like calling their __get__ (see bug #1785), so fall back to
         # looking in the __dict__.
         try:
-            value = getattr(object, key)
+            try:
+                value = getattr(object, key)
+            except Exception as e:
+                if isinstance(e, AttributeError):
+                    raise e
+                value = getattr_static(object, key)
             # handle the duplicate key
             if key in processed:
                 raise AttributeError


I am adding Yury. Removing 3.5 and 3.4 since they are in security fixes only mode.

Also see issue30533 a proposal for implementation of getmembers that uses getattr_static instead of getattr.


Thanks

----------
nosy: +yselivanov
versions:  -Python 3.4, Python 3.5

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