fix for test fail

docs/examples/introduction/stopwatch.py

@@ -72,7 +72,7 @@ class StopwatchApp(App):
     """A Textual app to manage stopwatches."""
 
     def compose(self) -> ComposeResult:
-        """Called to ad widgets to the app."""
+        """Called to add widgets to the app."""
         yield Header()
         yield Footer()
         yield Container(Stopwatch(), Stopwatch(), Stopwatch(), id="timers")

docs/examples/introduction/stopwatch06.py

@@ -72,7 +72,7 @@ class StopwatchApp(App):
     """A Textual app to manage stopwatches."""
 
     def compose(self) -> ComposeResult:
-        """Create child widgets for the app."""
+        """Called to add widgets to the app."""
         yield Header()
         yield Footer()
         yield Container(Stopwatch(), Stopwatch(), Stopwatch())

docs/introduction.md

@@ -2,7 +2,7 @@
 
 Welcome to the Textual Introduction!
 
-By the end of this page you should have a good idea of the steps involved in creating an application with Textual.
+By the end of this page you should have a solid understanding of app development with Textual.
 
 !!! quote
 

tests/utilities/test_app.py

@@ -103,6 +103,7 @@ class AppTest(App):
             # End of simulated time: we just shut down ourselves:
             assert not run_task.done()
             await self.shutdown()
+            await run_task
 
         return get_running_state_context_manager()