fix: keep generic metadata out of AttributeDict mappings

Author: wolph

progressbar/utils.py

@@ -521,6 +521,10 @@ class AttributeDict(dict[str, T], typing.Generic[T]):
     """
     A dict that can be accessed with .attribute.
 
+    Double-underscore names are stored as instance attributes instead of
+    dictionary entries. This keeps runtime metadata such as
+    ``__orig_class__`` out of the mapping contents.
+
     >>> attrs = AttributeDict(spam=123)
 
     # Reading
@@ -570,9 +574,15 @@ def __getattr__(self, name: str) -> T:
             raise AttributeError(f'No such attribute: {name}')
 
     def __setattr__(self, name: str, value: T) -> None:
+        if name.startswith('__') and name.endswith('__'):
+            object.__setattr__(self, name, value)
+            return
         self[name] = value
 
     def __delattr__(self, name: str) -> None:
+        if name.startswith('__') and name.endswith('__'):
+            object.__delattr__(self, name)
+            return
         if name in self:
             del self[name]
         else:

tests/test_stream.py

@@ -493,7 +493,7 @@ def test_redirect_stdout_unwrapped_after_keyboard_interrupt() -> None:
     # #212: when redirect_stdout wraps sys.stdout and iteration is abandoned
     # by a KeyboardInterrupt, the bar must unwrap stdout again. Runs in a
     # subprocess because stream wrapping mutates process-global sys.stdout.
-    child = textwrap.dedent(
+    child: str = textwrap.dedent(
         """
         import sys
         import progressbar
@@ -510,8 +510,13 @@ def test_redirect_stdout_unwrapped_after_keyboard_interrupt() -> None:
         sys.exit(2 if isinstance(sys.stdout, WrappingIO) else 0)
         """
     )
-    result = subprocess.run(
-        [sys.executable, '-c', child], capture_output=True, text=True
+    env: dict[str, str] = os.environ.copy()
+    env['PYTHONPATH'] = os.pathsep.join(sys.path)
+    result: subprocess.CompletedProcess[str] = subprocess.run(
+        [sys.executable, '-c', child],
+        capture_output=True,
+        text=True,
+        env=env,
     )
     assert result.returncode == 0, (
         f'stdout left wrapped after interrupt; rc={result.returncode}\n'
@@ -523,9 +528,7 @@ def test_wrap_logging_deduplicates_shared_handler(monkeypatch) -> None:
     # A handler attached to more than one logger must be wrapped only once.
     # _iter_loggers yields the root logger then named loggers, so a handler
     # shared by both is seen twice and the second visit is skipped.
-    for _ in range(5):
-        progressbar.streams.unwrap(stderr=True, stdout=True)
-    progressbar.streams.unwrap_logging()
+    reset_wrapped_streams()
 
     stream = io.StringIO()
     monkeypatch.setattr(sys, 'stderr', stream)

tests/test_utils.py

@@ -179,7 +179,9 @@ def test_attribute_dict_generic_value_type() -> None:
     # The generic upgrade lets homogeneous, explicitly-typed instances flow the
     # real value type. Runtime contract asserted here; the static benefit
     # (reveal_type -> int, mis-typed assignment flagged) is checked by pyright.
-    attrs: utils.AttributeDict[int] = utils.AttributeDict()
+    attrs: utils.AttributeDict[int] = utils.AttributeDict[int]()
+    assert attrs == {}
+    assert '__orig_class__' not in attrs
     attrs.count = 5
     assert attrs.count == 5
     assert attrs['count'] == 5
@@ -189,6 +191,18 @@ def test_attribute_dict_generic_value_type() -> None:
     assert mixed.b == 'x'
 
 
+def test_attribute_dict_dunder_attributes_use_instance_storage() -> None:
+    attrs: utils.AttributeDict[str] = utils.AttributeDict()
+    attrs.__probe__ = 'metadata'
+
+    assert attrs.__probe__ == 'metadata'
+    assert '__probe__' not in attrs
+
+    del attrs.__probe__
+    with pytest.raises(AttributeError):
+        _ = attrs.__probe__
+
+
 def test_stream_wrapper_unwrap_restores_excepthook() -> None:
     # Regression: C7 - unwrap_stdout/unwrap_stderr left the custom
     # excepthook installed forever.