fix: fix remove_lut_view on unowned LUTViews (#247)

* fix: fix remove_lut_view on unowned LUTViews

* more robust test

Author: tlambert03

src/ndv/views/_jupyter/_array_view.py

@@ -562,6 +562,8 @@ def add_lut_view(self, channel: ChannelKey) -> JupyterLUTView:
 
     def remove_lut_view(self, view: LUTView) -> None:
         """Remove a LUT view from the viewer."""
+        if view not in self._luts.values():
+            return
         view = cast("JupyterLUTView", view)
         layout = self._luts_box
         layout.children = tuple(

src/ndv/views/_qt/_array_view.py

@@ -844,6 +844,8 @@ def add_lut_view(self, channel: ChannelKey) -> QLUTView:
         return view
 
     def remove_lut_view(self, view: LUTView) -> None:
+        if view not in self._luts.values():
+            return
         self._qwidget.luts.removeWidget(cast("QLUTView", view).frontend_widget())
 
     def _on_channel_mode_changed(self, text: str) -> None:

src/ndv/views/_wx/_array_view.py

@@ -782,6 +782,9 @@ def add_histogram(self, channel: ChannelKey, widget: HistogramCanvas) -> None:
         self._wxwidget.Layout()
 
     def remove_lut_view(self, lut: LUTView) -> None:
+        if lut not in self._luts.values():
+            return
+
         # Find the channel key for this LUT view
         channel_to_remove = next(
             (channel for channel, view in self._luts.items() if view == lut), None

tests/test_controller.py

@@ -648,6 +648,24 @@ def test_data_replacement_with_stale_index() -> None:
     ctrl._join()
 
 
+@no_type_check
+@_patch_views
+def test_remove_lut_view_with_non_gui_view() -> None:
+    """remove_lut_view should handle non-GUI LUTViews (e.g. ImageHandle).
+
+    See https://github.com/pyapp-kit/ndv/issues/138
+    """
+    ctrl = ArrayViewer()
+    ctrl._async = False
+    ctrl.data = np.random.randint(0, 255, size=(10, 10), dtype="uint8")
+
+    lut_ctrl = next(iter(ctrl._lut_controllers.values()))
+    # lut_views contains both the GUI LUTView and the ImageHandle
+    for view in lut_ctrl.lut_views:
+        # This should not raise, even for non-GUI views like ImageHandle
+        ctrl._view.remove_lut_view(view)
+
+
 @no_type_check
 @_patch_views
 def test_user_current_index_preserved_on_init() -> None: