Typing fixes from review

core/pyproject.toml

@@ -76,7 +76,6 @@ dev = [
     "pytest-freezer == 0.4.8",
     "setuptools-scm == 8.1.0",
     "tox == 4.15.0",
-    "types-Pillow == 10.1.0.2",  # TODO:PR: does this help anything?
     # typing-extensions needed for TypeAlias added in Py 3.10
     "typing-extensions == 4.9.0 ; python_version < '3.10'",
 ]

core/src/toga/app.py

@@ -6,7 +6,7 @@
 import sys
 import warnings
 import webbrowser
-from collections.abc import Iterator, Set
+from collections.abc import Iterator
 from email.message import Message
 from pathlib import Path
 from typing import TYPE_CHECKING, Any, MutableSet, Protocol
@@ -100,7 +100,7 @@ def discard(self, window: Window) -> None:
     # 2023-10: Backwards compatibility
     ######################################################################
 
-    def __iadd__(self, window: Set[Any]) -> WindowSet:
+    def __iadd__(self, window: Window) -> WindowSet:
         # The standard set type does not have a += operator.
         warn(
             "Windows are automatically associated with the app; += is not required",
@@ -109,7 +109,7 @@ def __iadd__(self, window: Set[Any]) -> WindowSet:
         )
         return self
 
-    def __isub__(self, other: Set[Any]) -> WindowSet:
+    def __isub__(self, other: Window) -> WindowSet:
         # The standard set type does have a -= operator, but it takes sets rather than
         # individual items.
         warn(

core/src/toga/command.py

@@ -295,8 +295,12 @@ def __eq__(self, other: object) -> bool:
 
 
 class CommandSetChangeHandler(Protocol):
-    def __call__(self, /) -> object:
-        """A handler that will be invoked when a Command or Group is added to the CommandSet."""
+    def __call__(self, **kwargs) -> object:
+        """A handler that will be invoked when a Command or Group is added to the
+        CommandSet.
+
+        :param kwargs: Ensures compatibility with arguments added in future versions.
+        """
 
 
 class CommandSet:

core/src/toga/hardware/location.py

@@ -21,7 +21,7 @@ def __call__(
         location: toga.LatLng,
         altitude: float | None,
         **kwargs: Any,
-    ) -> None:
+    ) -> object:
         """A handler that will be invoked when the user's location changes.
 
         :param service: the location service that generated the update.

core/src/toga/images.py

@@ -34,7 +34,7 @@
     ImageContent: TypeAlias = PathLike | BytesLike | ImageLike
 
     # Define a type variable representing an image of an externally defined type.
-    ExternalImageT = TypeVar("ExternalImageT", bound=object)
+    ExternalImageT = TypeVar("ExternalImageT")
 
 
 class ImageConverter(Protocol):

core/src/toga/widgets/canvas.py

@@ -1174,7 +1174,7 @@ def color(self, value: object) -> None:
 
 
 class OnTouchHandler(Protocol):
-    def __call__(self, widget: Canvas, x: int, y: int, **kwargs: Any) -> None:
+    def __call__(self, widget: Canvas, x: int, y: int, **kwargs: Any) -> object:
         """A handler that will be invoked when a :any:`Canvas` is touched with a finger
         or mouse.
 
@@ -1186,7 +1186,13 @@ def __call__(self, widget: Canvas, x: int, y: int, **kwargs: Any) -> None:
 
 
 class OnResizeHandler(Protocol):
-    def __call__(self, widget: Canvas, width: int, height: int, **kwargs: Any) -> None:
+    def __call__(
+        self,
+        widget: Canvas,
+        width: int,
+        height: int,
+        **kwargs: Any,
+    ) -> object:
         """A handler that will be invoked when a :any:`Canvas` is resized.
 
         :param widget: The canvas that was resized.

core/src/toga/widgets/dateinput.py

@@ -18,9 +18,10 @@
 
 
 class OnChangeHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> None:
+    def __call__(self, widget: DateInput, **kwargs: Any) -> object:
         """A handler that will be invoked when a change occurs.
 
+        :param widget: The DateInput that was changed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/detailedlist.py

@@ -21,35 +21,39 @@
 
 
 class OnPrimaryActionHandler(Protocol):
-    def __call__(self, row: Any, **kwargs: Any) -> object:
+    def __call__(self, widget: DetailedList, row: Any, **kwargs: Any) -> object:
         """A handler to invoke for the primary action.
 
-        :param widget: The button that was pressed.
+        :param widget: The DetailedList that was invoked.
+        :param row: The current row for the detailed list.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnSecondaryActionHandler(Protocol):
-    def __call__(self, row: Any, **kwargs: Any) -> object:
+    def __call__(self, widget: DetailedList, row: Any, **kwargs: Any) -> object:
         """A handler to invoke for the secondary action.
 
+        :param widget: The DetailedList that was invoked.
         :param row: The current row for the detailed list.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnRefreshHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: DetailedList, **kwargs: Any) -> object:
         """A handler to invoke when the detailed list is refreshed.
 
+        :param widget: The DetailedList that was refreshed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnSelectHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: DetailedList, **kwargs: Any) -> object:
         """A handler to invoke when the detailed list is selected.
 
+        :param widget: The DetailedList that was selected.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/mapview.py

@@ -125,7 +125,7 @@ class OnSelectHandler(Protocol):
     def __call__(self, widget: MapView, *, pin: MapPin, **kwargs: Any) -> object:
         """A handler that will be invoked when the user selects a map pin.
 
-        :param widget: The button that was pressed.
+        :param widget: The MapView that was selected.
         :param pin: The pin that was selected.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """

core/src/toga/widgets/multilinetextinput.py

@@ -9,9 +9,10 @@
 
 
 class OnChangeHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: MultilineTextInput, **kwargs: Any) -> object:
         """A handler to invoke when the value is changed.
 
+        :param widget: The MultilineTextInput that was changed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/numberinput.py

@@ -68,9 +68,10 @@ def _clean_decimal_str(value: str) -> str:
 
 
 class OnChangeHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: NumberInput, **kwargs: Any) -> object:
         """A handler to invoke when the value is changed.
 
+        :param widget: The NumberInput that was changed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/optioncontainer.py

@@ -1,12 +1,7 @@
 from __future__ import annotations
 
 from collections.abc import Iterable
-from typing import (
-    TYPE_CHECKING,
-    Any,
-    Protocol,
-    overload,
-)
+from typing import TYPE_CHECKING, Any, Protocol, overload
 
 import toga
 from toga.handlers import wrapped_handler
@@ -27,9 +22,10 @@
 
 
 class OnSelectHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
-        """A handler to invoke when the option list is selected.
+    def __call__(self, widget: OptionContainer, **kwargs: Any) -> None:
+        """A handler that will be invoked when a new tab is selected in the OptionContainer.
 
+        :param widget: The OptionContainer that had a selection change.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
@@ -380,7 +376,7 @@ def __init__(
         self,
         id: str | None = None,
         style: StyleT | None = None,
-        content: Iterable[tuple[str, Widget]] | None = None,
+        content: Iterable[OptionContainerContent] | None = None,
         on_select: toga.widgets.optioncontainer.OnSelectHandler | None = None,
     ):
         """Create a new OptionContainer.

core/src/toga/widgets/scrollcontainer.py

@@ -8,9 +8,10 @@
 
 
 class OnScrollHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: ScrollContainer, **kwargs: Any) -> object:
         """A handler to invoke when the container is scrolled.
 
+        :param widget: The ScrollContainer that was scrolled.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/selection.py

@@ -15,9 +15,10 @@
 
 
 class OnChangeHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: Selection, **kwargs: Any) -> object:
         """A handler to invoke when the value is changed.
 
+        :param widget: The Selection that was changed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/slider.py

@@ -12,25 +12,28 @@
 
 
 class OnChangeHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: Slider, **kwargs: Any) -> object:
         """A handler to invoke when the value is changed.
 
+        :param widget: The Slider that was changed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnPressHandler(Protocol):
-    def __call__(self, **kwargs) -> object:
+    def __call__(self, widget: Slider, **kwargs) -> object:
         """A handler to invoke when the slider is pressed.
 
+        :param widget: The Slider that was pressed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnReleaseHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: Slider, **kwargs: Any) -> object:
         """A handler to invoke when the slider is pressed.
 
+        :param widget: The Slider that was released.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/switch.py

@@ -9,9 +9,10 @@
 
 
 class OnChangeHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: Switch, **kwargs: Any) -> object:
         """A handler to invoke when the value is changed.
 
+        :param widget: The Switch that was changed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/table.py

@@ -16,17 +16,20 @@
 
 
 class OnSelectHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: Table, **kwargs: Any) -> object:
         """A handler to invoke when the table is selected.
 
+        :param widget: The Table that was selected.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnActivateHandler(Protocol):
-    def __call__(self, row: Any, **kwargs: Any) -> object:
+    def __call__(self, widget: Table, row: Any, **kwargs: Any) -> object:
         """A handler to invoke when the table is activated.
 
+        :param widget: The Table that was activated.
+        :param row: The Table Row that was activated.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/textinput.py

@@ -10,33 +10,37 @@
 
 
 class OnChangeHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: TextInput, **kwargs: Any) -> object:
         """A handler to invoke when the text input is changed.
 
+        :param widget: The TextInput that was changed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnConfirmHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: TextInput, **kwargs: Any) -> object:
         """A handler to invoke when the text input is confirmed.
 
+        :param widget: The TextInput that was confirmed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnGainFocusHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: TextInput, **kwargs: Any) -> object:
         """A handler to invoke when the text input gains focus.
 
+        :param widget: The TextInput that gained focus.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnLoseFocusHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: TextInput, **kwargs: Any) -> object:
         """A handler to invoke when the text input loses focus.
 
+        :param widget: The TextInput that lost focus.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/timeinput.py

@@ -11,9 +11,10 @@
 
 
 class OnChangeHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: TimeInput, **kwargs: Any) -> object:
         """A handler to invoke when the time input is changed.
 
+        :param widget: The TimeInput that was changed.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/tree.py

@@ -18,17 +18,19 @@
 
 
 class OnSelectHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: Tree, **kwargs: Any) -> object:
         """A handler to invoke when the tree is selected.
 
+        :param widget: The Tree that was selected.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 
 
 class OnActivateHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: Tree, **kwargs: Any) -> object:
         """A handler to invoke when the tree is activated.
 
+        :param widget: The Tree that was activated.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """
 

core/src/toga/widgets/webview.py

@@ -14,9 +14,10 @@ class JavaScriptResult(AsyncResult):
 
 
 class OnWebViewLoadHandler(Protocol):
-    def __call__(self, **kwargs: Any) -> object:
+    def __call__(self, widget: WebView, **kwargs: Any) -> object:
         """A handler to invoke when the WebView is loaded.
 
+        :param widget: The WebView that was loaded.
         :param kwargs: Ensures compatibility with arguments added in future versions.
         """