feat: make AttributeDict generic over its value type

Author: wolph

progressbar/utils.py

@@ -517,7 +517,7 @@ def excepthook(
         self.flush()
 
 
-class AttributeDict(dict):
+class AttributeDict(dict[str, T], typing.Generic[T]):
     """
     A dict that can be accessed with .attribute.
 
@@ -563,13 +563,13 @@ class AttributeDict(dict):
     AttributeError: No such attribute: spam
     """
 
-    def __getattr__(self, name: str) -> typing.Any:
+    def __getattr__(self, name: str) -> T:
         if name in self:
             return self[name]
         else:
             raise AttributeError(f'No such attribute: {name}')
 
-    def __setattr__(self, name: str, value: typing.Any) -> None:
+    def __setattr__(self, name: str, value: T) -> None:
         self[name] = value
 
     def __delattr__(self, name: str) -> None:

tests/test_utils.py

@@ -175,6 +175,20 @@ def test_attribute_dict_set_get_del() -> None:
         del attrs.spam
 
 
+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.count = 5
+    assert attrs.count == 5
+    assert attrs['count'] == 5
+
+    mixed = utils.AttributeDict(a=1, b='x')
+    assert mixed.a == 1
+    assert mixed.b == 'x'
+
+
 def test_stream_wrapper_unwrap_restores_excepthook() -> None:
     # Regression: C7 - unwrap_stdout/unwrap_stderr left the custom
     # excepthook installed forever.