Isolate the command palette from app-based queries

This fixes Textualize#3633 by ensuring that if a query is made against the app while
the command palette is active, the query trickles down to the
previously-active screen rather than into the command palette modal screen.

This also updates the command palette unit tests to take this change into
account.

src/textual/app.py

@@ -600,7 +600,7 @@ def children(self) -> Sequence["Widget"]:
             A sequence of widgets.
         """
         try:
-            return (self.screen,)
+            return (CommandPalette.current_screen(self),)
         except ScreenError:
             return ()
 

src/textual/command.py

@@ -475,6 +475,21 @@ def is_open(app: App) -> bool:
         """
         return app.screen.id == CommandPalette._PALETTE_ID
 
+    @staticmethod
+    def current_screen(app: App) -> Screen:
+        """Get the current screen.
+
+        This method gets the current screen for the app, ignoring the
+        command palette.
+
+        Args:
+            app: The app to get the screen for.
+
+        Returns:
+            The current screen for the application, excluding the command palette.
+        """
+        return app.screen_stack[-2] if CommandPalette.is_open(app) else app.screen
+
     @property
     def _provider_classes(self) -> set[type[Provider]]:
         """The currently available command providers.
@@ -519,8 +534,8 @@ def _on_click(self, event: Click) -> None:
             self.dismiss()
 
     def on_mount(self, _: Mount) -> None:
-        """Capture the calling screen."""
-        self._calling_screen = self.app.screen_stack[-2]
+        """Configure the command palette once the DOM is ready."""
+        self._calling_screen = self.current_screen(self.app)
 
         match_style = self.get_component_rich_style(
             "command-palette--highlight", partial=True

tests/command_palette/test_click_away.py

@@ -20,6 +20,6 @@ def on_mount(self) -> None:
 async def test_clicking_outside_command_palette_closes_it() -> None:
     """Clicking 'outside' the command palette should make it go away."""
     async with CommandPaletteApp().run_test() as pilot:
-        assert len(pilot.app.query(CommandPalette)) == 1
+        assert isinstance(pilot.app.screen, CommandPalette)
         await pilot.click()
-        assert len(pilot.app.query(CommandPalette)) == 0
+        assert not isinstance(pilot.app.screen, CommandPalette)

tests/command_palette/test_command_source_environment.py

@@ -31,7 +31,7 @@ def on_mount(self) -> None:
 async def test_command_source_environment() -> None:
     """The command source should see the app and default screen."""
     async with CommandPaletteApp().run_test() as pilot:
-        base_screen = pilot.app.query_one(CommandPalette)._calling_screen
+        base_screen = CommandPalette.current_screen(pilot.app)
         assert base_screen is not None
         await pilot.press(*"test")
         assert len(SimpleSource.environment) == 1

tests/command_palette/test_declare_sources.py

@@ -28,7 +28,8 @@ class AppWithNoSources(AppWithActiveCommandPalette):
 async def test_no_app_command_sources() -> None:
     """An app with no sources declared should work fine."""
     async with AppWithNoSources().run_test() as pilot:
-        assert pilot.app.query_one(CommandPalette)._provider_classes == App.COMMANDS
+        assert isinstance(pilot.app.screen, CommandPalette)
+        assert pilot.app.screen._provider_classes == App.COMMANDS
 
 
 class AppWithSources(AppWithActiveCommandPalette):
@@ -38,10 +39,8 @@ class AppWithSources(AppWithActiveCommandPalette):
 async def test_app_command_sources() -> None:
     """Command sources declared on an app should be in the command palette."""
     async with AppWithSources().run_test() as pilot:
-        assert (
-            pilot.app.query_one(CommandPalette)._provider_classes
-            == AppWithSources.COMMANDS
-        )
+        assert isinstance(pilot.app.screen, CommandPalette)
+        assert pilot.app.screen._provider_classes == AppWithSources.COMMANDS
 
 
 class AppWithInitialScreen(App[None]):
@@ -61,7 +60,8 @@ def on_mount(self) -> None:
 async def test_no_screen_command_sources() -> None:
     """An app with a screen with no sources declared should work fine."""
     async with AppWithInitialScreen(ScreenWithNoSources()).run_test() as pilot:
-        assert pilot.app.query_one(CommandPalette)._provider_classes == App.COMMANDS
+        assert isinstance(pilot.app.screen, CommandPalette)
+        assert pilot.app.screen._provider_classes == App.COMMANDS
 
 
 class ScreenWithSources(ScreenWithNoSources):
@@ -71,8 +71,9 @@ class ScreenWithSources(ScreenWithNoSources):
 async def test_screen_command_sources() -> None:
     """Command sources declared on a screen should be in the command palette."""
     async with AppWithInitialScreen(ScreenWithSources()).run_test() as pilot:
+        assert isinstance(pilot.app.screen, CommandPalette)
         assert (
-            pilot.app.query_one(CommandPalette)._provider_classes
+            pilot.app.screen._provider_classes
             == App.COMMANDS | ScreenWithSources.COMMANDS
         )
 
@@ -91,7 +92,8 @@ def on_mount(self) -> None:
 async def test_app_and_screen_command_sources_combine() -> None:
     """If an app and the screen have command sources they should combine."""
     async with CombinedSourceApp().run_test() as pilot:
+        assert isinstance(pilot.app.screen, CommandPalette)
         assert (
-            pilot.app.query_one(CommandPalette)._provider_classes
+            pilot.app.screen._provider_classes
             == CombinedSourceApp.COMMANDS | ScreenWithSources.COMMANDS
         )

tests/command_palette/test_escaping.py

@@ -20,31 +20,31 @@ def on_mount(self) -> None:
 async def test_escape_closes_when_no_list_visible() -> None:
     """Pressing escape when no list is visible should close the command palette."""
     async with CommandPaletteApp().run_test() as pilot:
-        assert len(pilot.app.query(CommandPalette)) == 1
+        assert CommandPalette.is_open(pilot.app)
         await pilot.press("escape")
-        assert len(pilot.app.query(CommandPalette)) == 0
+        assert not CommandPalette.is_open(pilot.app)
 
 
 async def test_escape_does_not_close_when_list_visible() -> None:
     """Pressing escape when a hit list is visible should not close the command palette."""
     async with CommandPaletteApp().run_test() as pilot:
-        assert len(pilot.app.query(CommandPalette)) == 1
+        assert CommandPalette.is_open(pilot.app)
         await pilot.press("a")
         await pilot.press("escape")
-        assert len(pilot.app.query(CommandPalette)) == 1
+        assert CommandPalette.is_open(pilot.app)
         await pilot.press("escape")
-        assert len(pilot.app.query(CommandPalette)) == 0
+        assert not CommandPalette.is_open(pilot.app)
 
 
 async def test_down_arrow_should_undo_closing_of_list_via_escape() -> None:
     """Down arrow should reopen the hit list if escape closed it before."""
     async with CommandPaletteApp().run_test() as pilot:
-        assert len(pilot.app.query(CommandPalette)) == 1
+        assert CommandPalette.is_open(pilot.app)
         await pilot.press("a")
         await pilot.press("escape")
-        assert len(pilot.app.query(CommandPalette)) == 1
+        assert CommandPalette.is_open(pilot.app)
         await pilot.press("down")
         await pilot.press("escape")
-        assert len(pilot.app.query(CommandPalette)) == 1
+        assert CommandPalette.is_open(pilot.app)
         await pilot.press("escape")
-        assert len(pilot.app.query(CommandPalette)) == 0
+        assert not CommandPalette.is_open(pilot.app)

tests/command_palette/test_interaction.py

@@ -21,46 +21,46 @@ def on_mount(self) -> None:
 async def test_initial_list_no_highlight() -> None:
     """When the list initially appears, nothing will be highlighted."""
     async with CommandPaletteApp().run_test() as pilot:
-        assert len(pilot.app.query(CommandPalette)) == 1
-        assert pilot.app.query_one(CommandList).visible is False
+        assert CommandPalette.is_open(pilot.app)
+        assert pilot.app.screen.query_one(CommandList).visible is False
         await pilot.press("a")
-        assert pilot.app.query_one(CommandList).visible is True
-        assert pilot.app.query_one(CommandList).highlighted is None
+        assert pilot.app.screen.query_one(CommandList).visible is True
+        assert pilot.app.screen.query_one(CommandList).highlighted is None
 
 
 async def test_down_arrow_selects_an_item() -> None:
     """Typing in a search value then pressing down should select a command."""
     async with CommandPaletteApp().run_test() as pilot:
-        assert len(pilot.app.query(CommandPalette)) == 1
-        assert pilot.app.query_one(CommandList).visible is False
+        assert CommandPalette.is_open(pilot.app)
+        assert pilot.app.screen.query_one(CommandList).visible is False
         await pilot.press("a")
-        assert pilot.app.query_one(CommandList).visible is True
-        assert pilot.app.query_one(CommandList).highlighted is None
+        assert pilot.app.screen.query_one(CommandList).visible is True
+        assert pilot.app.screen.query_one(CommandList).highlighted is None
         await pilot.press("down")
-        assert pilot.app.query_one(CommandList).highlighted is not None
+        assert pilot.app.screen.query_one(CommandList).highlighted is not None
 
 
 async def test_enter_selects_an_item() -> None:
     """Typing in a search value then pressing enter should select a command."""
     async with CommandPaletteApp().run_test() as pilot:
-        assert len(pilot.app.query(CommandPalette)) == 1
-        assert pilot.app.query_one(CommandList).visible is False
+        assert CommandPalette.is_open(pilot.app)
+        assert pilot.app.screen.query_one(CommandList).visible is False
         await pilot.press("a")
-        assert pilot.app.query_one(CommandList).visible is True
-        assert pilot.app.query_one(CommandList).highlighted is None
+        assert pilot.app.screen.query_one(CommandList).visible is True
+        assert pilot.app.screen.query_one(CommandList).highlighted is None
         await pilot.press("enter")
-        assert pilot.app.query_one(CommandList).highlighted is not None
+        assert pilot.app.screen.query_one(CommandList).highlighted is not None
 
 
 async def test_selection_of_command_closes_command_palette() -> None:
     """Selecting a command from the list should close the list."""
     async with CommandPaletteApp().run_test() as pilot:
-        assert len(pilot.app.query(CommandPalette)) == 1
-        assert pilot.app.query_one(CommandList).visible is False
+        assert CommandPalette.is_open(pilot.app)
+        assert pilot.app.screen.query_one(CommandList).visible is False
         await pilot.press("a")
-        assert pilot.app.query_one(CommandList).visible is True
-        assert pilot.app.query_one(CommandList).highlighted is None
+        assert pilot.app.screen.query_one(CommandList).visible is True
+        assert pilot.app.screen.query_one(CommandList).highlighted is None
         await pilot.press("enter")
-        assert pilot.app.query_one(CommandList).highlighted is not None
+        assert pilot.app.screen.query_one(CommandList).highlighted is not None
         await pilot.press("enter")
-        assert len(pilot.app.query(CommandPalette)) == 0
+        assert not CommandPalette.is_open(pilot.app)

tests/command_palette/test_no_results.py

@@ -13,7 +13,7 @@ def on_mount(self) -> None:
 async def test_no_results() -> None:
     """Receiving no results from a search for a command should not be a problem."""
     async with CommandPaletteApp().run_test() as pilot:
-        assert len(pilot.app.query(CommandPalette)) == 1
+        assert CommandPalette.is_open(pilot.app)
         results = pilot.app.screen.query_one(OptionList)
         assert results.visible is False
         assert results.option_count == 0

tests/command_palette/test_run_on_select.py

@@ -37,7 +37,7 @@ async def test_with_run_on_select_on() -> None:
         assert isinstance(pilot.app, CommandPaletteRunOnSelectApp)
         pilot.app.action_command_palette()
         await pilot.press("0")
-        await pilot.app.query_one(CommandPalette).workers.wait_for_complete()
+        await pilot.app.screen.workers.wait_for_complete()
         await pilot.press("down")
         await pilot.press("enter")
         assert pilot.app.selection is not None
@@ -57,11 +57,11 @@ async def test_with_run_on_select_off() -> None:
         assert isinstance(pilot.app, CommandPaletteDoNotRunOnSelectApp)
         pilot.app.action_command_palette()
         await pilot.press("0")
-        await pilot.app.query_one(CommandPalette).workers.wait_for_complete()
+        await pilot.app.screen.workers.wait_for_complete()
         await pilot.press("down")
         await pilot.press("enter")
         assert pilot.app.selection is None
-        assert pilot.app.query_one(Input).value != ""
+        assert pilot.app.screen.query_one(Input).value != ""
         await pilot.press("enter")
         assert pilot.app.selection is not None
         CommandPalette.run_on_select = save

tests/snapshot_tests/test_snapshots.py

@@ -669,15 +669,12 @@ async def run_before(pilot) -> None:
 
 
 def test_command_palette(snap_compare) -> None:
-    from textual.command import CommandPalette
 
     async def run_before(pilot) -> None:
-        palette = pilot.app.query_one(CommandPalette)
-        palette_input = palette.query_one(Input)
-        palette_input.cursor_blink = False
-        await pilot.press("ctrl+backslash")
+        #await pilot.press("ctrl+backslash")
+        pilot.app.screen.query_one(Input).cursor_blink = False
         await pilot.press("A")
-        await pilot.app.query_one(CommandPalette).workers.wait_for_complete()
+        await pilot.app.screen.workers.wait_for_complete()
 
     assert snap_compare(SNAPSHOT_APPS_DIR / "command_palette.py", run_before=run_before)