Issue 9732: addition of getattr_static to the inspect module
diff --git a/Lib/inspect.py b/Lib/inspect.py
index 5f92787..57d8c72 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -1054,3 +1054,67 @@
def trace(context=1):
"""Return a list of records for the stack below the current exception."""
return getinnerframes(sys.exc_info()[2], context)
+
+
+# ------------------------------------------------ static version of getattr
+
+_sentinel = object()
+
+def _check_instance(obj, attr):
+ instance_dict = {}
+ try:
+ instance_dict = object.__getattribute__(obj, "__dict__")
+ except AttributeError:
+ pass
+ return instance_dict.get(attr, _sentinel)
+
+
+def _check_class(klass, attr):
+ for entry in getmro(klass):
+ try:
+ return entry.__dict__[attr]
+ except KeyError:
+ pass
+ return _sentinel
+
+
+def getattr_static(obj, attr, default=_sentinel):
+ """Retrieve attributes without triggering dynamic lookup via the
+ descriptor protocol, __getattr__ or __getattribute__.
+
+ Note: this function may not be able to retrieve all attributes
+ that getattr can fetch (like dynamically created attributes)
+ and may find attributes that getattr can't (like descriptors
+ that raise AttributeError). It can also return descriptor objects
+ instead of instance members in some cases. See the
+ documentation for details.
+ """
+ instance_result = _sentinel
+ if not isinstance(obj, type):
+ instance_result = _check_instance(obj, attr)
+ klass = obj.__class__
+ else:
+ klass = obj
+
+ klass_result = _check_class(klass, attr)
+
+ if instance_result is not _sentinel and klass_result is not _sentinel:
+ if (_check_class(type(klass_result), '__get__') is not _sentinel and
+ _check_class(type(klass_result), '__set__') is not _sentinel):
+ return klass_result
+
+ if instance_result is not _sentinel:
+ return instance_result
+ if klass_result is not _sentinel:
+ return klass_result
+
+ if obj is klass:
+ # for types we check the metaclass too
+ for entry in getmro(type(klass)):
+ try:
+ return entry.__dict__[attr]
+ except KeyError:
+ pass
+ if default is not _sentinel:
+ return default
+ raise AttributeError(attr)