Merge pull request #4786 from Textualize/fix-select-remove

Fix select remove

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Fixed
 
 - Fixed issues in Kitty terminal after exiting app https://github.com/Textualize/textual/issues/4779
+- Fixed exception when removing Selects https://github.com/Textualize/textual/pull/4786
 
 ## [0.73.0] - 2024-07-18
 

src/textual/widgets/_select.py

@@ -493,7 +493,11 @@ def _on_mount(self, _event: events.Mount) -> None:
 
     def _watch_expanded(self, expanded: bool) -> None:
         """Display or hide overlay."""
-        overlay = self.query_one(SelectOverlay)
+        try:
+            overlay = self.query_one(SelectOverlay)
+        except NoMatches:
+            # The widget has likely been removed
+            return
         self.set_class(expanded, "-expanded")
         if expanded:
             overlay.focus()

tests/select/test_remove.py

@@ -0,0 +1,25 @@
+from textual.app import App, ComposeResult
+from textual.widgets import Header, Select
+
+LINES = """I must not fear.
+Fear is the mind-killer.
+Fear is the little-death that brings total obliteration.
+I will face my fear.
+I will permit it to pass over me and through me.""".splitlines()
+
+
+async def test_select_remove():
+    # Regression test for https://github.com/Textualize/textual/issues/4782
+    class SelectApp(App):
+        def compose(self) -> ComposeResult:
+            self.select = Select((line, line) for line in LINES)
+            self.select.watch_value = self.on_select
+            yield Header()
+            yield self.select
+
+        def on_select(self):
+            self.select.remove()
+
+    app = SelectApp()
+    async with app.run_test() as pilot:
+        await pilot.press("enter", "down", "down", "enter")