test: inline smoke check for the wheel guard

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/aare/gui/widgets/wheel_value_guard.py

@@ -46,3 +46,37 @@ class WheelValueGuard(QObject):
                 QApplication.sendEvent(area.viewport(), relayed)
             return True
         return super().eventFilter(obj, event)
+
+
+if __name__ == "__main__":
+    # ponytail: smallest check that fails if the guard logic breaks
+    import os
+
+    os.environ.setdefault("QT_QPA_PLATFORM", "offscreen")
+    from PySide6.QtCore import QPoint, QPointF
+
+    app = QApplication([])
+    guard = WheelValueGuard()
+    app.installEventFilter(guard)
+    slider = QSlider(Qt.Orientation.Horizontal)
+    slider.setRange(0, 100)
+    slider.setValue(50)
+    slider.show()
+
+    def wheel(buttons):
+        return QWheelEvent(
+            QPointF(5, 5),
+            QPointF(5, 5),
+            QPoint(0, 0),
+            QPoint(0, 120),
+            buttons,
+            Qt.KeyboardModifier.NoModifier,
+            Qt.ScrollPhase.NoScrollPhase,
+            False,
+        )
+
+    QApplication.sendEvent(slider, wheel(Qt.MouseButton.NoButton))
+    assert slider.value() == 50, "bare wheel must not adjust the slider"
+    QApplication.sendEvent(slider, wheel(Qt.MouseButton.RightButton))
+    assert slider.value() != 50, "right-button + wheel must adjust the slider"
+    print("gude")