fix(tui): ignore stale overview refreshes

Author: coreyt

airlock/tui/screens/overview.py

@@ -19,6 +19,7 @@
 from textual.app import ComposeResult
 from textual.binding import Binding
 from textual.containers import Horizontal, Vertical, VerticalScroll
+from textual.css.query import NoMatches
 from textual.strip import Strip
 from textual.widgets import Button, Collapsible, DataTable, RichLog, Static
 
@@ -1002,8 +1003,21 @@ def _refresh_state(self) -> None:
 
         # --- push to UI ---
         def _update_ui() -> None:
+            # This worker can finish after its pane has been replaced while
+            # navigating the TUI.  In that case the scheduled UI callback is
+            # stale: querying the former pane's children raises NoMatches and
+            # turns a harmless teardown race into a failed Textual worker.
+            if not self.is_mounted:
+                return
+
             # Providers table
-            ptable = self.query_one("#ov-providers", _SafeDataTable)
+            try:
+                ptable = self.query_one("#ov-providers", _SafeDataTable)
+            except NoMatches:
+                # The overview pane may remain mounted for a moment after its
+                # children are removed during a screen switch or app teardown.
+                # This callback came from the background refresh and is stale.
+                return
             ptable.clear()
             if provider_rows:
                 for row, key in zip(provider_rows, provider_keys):

tests/test_tui.py

@@ -1253,7 +1253,7 @@ def test_guards_render_pipeline_escapes_request_metadata() -> None:
     assert r"\[bold red]ACT\[/]" in out
 
 
-async def test_overview_no_data_for_provider_escapes_name() -> None:
+async def test_overview_no_data_for_provider_escapes_name(fresh_state_store) -> None:
     """Early-return branch in _show_provider_detail must escape markup in
     the provider name so injected tags aren't interpreted as Rich markup."""
     from textual.widgets import Static
@@ -1275,7 +1275,7 @@ async def test_overview_no_data_for_provider_escapes_name() -> None:
         assert r"\[bold red]INJECT\[/]" in raw
 
 
-async def test_overview_no_data_for_model_escapes_name() -> None:
+async def test_overview_no_data_for_model_escapes_name(fresh_state_store) -> None:
     """Early-return branch in _show_model_detail must escape markup in
     the model name."""
     from textual.widgets import Static