<li>the statement lists in each case, including the default, end in a terminating
	    statement, or a possibly labeled <a href="#Fallthrough_statements">"fallthrough"
	    statement</a>.</li>
	</ul>
</li>

<li>
	A <a href="#Select_statements">"select" statement</a> in which:
	<ul>
	<li>there are no "break" statements referring to the "select" statement, and</li>

# Testing WebSockets { #testing-websockets }

You can use the same `TestClient` to test WebSockets.

For this, you use the `TestClient` in a `with` statement, connecting to the WebSocket:

{* ../../docs_src/app_testing/tutorial002_py39.py hl[27:31] *}

/// note

For more details, check Starlette's documentation for <a href="https://www.starlette.dev/testclient/#testing-websocket-sessions" class="external-link" target="_blank">testing WebSockets</a>.

* unload: quitar de memoria (do not translate to "descargar")
* mount (noun): mount (do not translate to "montura")
* mount (verb): montar
* statement (as in code statement): statement (do not translate to "declaración" or "sentencia")
* worker process: worker process (do not translate to "proceso trabajador" or "proceso de trabajo")

# Eventos de testing: lifespan y startup - shutdown { #testing-events-lifespan-and-startup-shutdown }

Cuando necesitas que `lifespan` se ejecute en tus tests, puedes usar el `TestClient` con un statement `with`:

{* ../../docs_src/app_testing/tutorial004_py39.py hl[9:15,18,27:28,30:32,41:43] *}


Puedes leer más detalles sobre ["Ejecutar lifespan en tests en el sitio oficial de documentación de Starlette."](https://www.starlette.dev/lifespan/#running-lifespan-in-tests)

# Probando WebSockets { #testing-websockets }

Puedes usar el mismo `TestClient` para probar WebSockets.

Para esto, usas el `TestClient` en un statement `with`, conectándote al WebSocket:

{* ../../docs_src/app_testing/tutorial002_py39.py hl[27:31] *}

/// note | Nota

Only the code prior to and including the `yield` statement is executed before creating a response:

{* ../../docs_src/dependencies/tutorial007_py39.py hl[2:4] *}

The yielded value is what is injected into *path operations* and other dependencies:

{* ../../docs_src/dependencies/tutorial007_py39.py hl[4] *}

The code following the `yield` statement is executed after the response:

# Testing Events: lifespan and startup - shutdown { #testing-events-lifespan-and-startup-shutdown }

When you need `lifespan` to run in your tests, you can use the `TestClient` with a `with` statement:

{* ../../docs_src/app_testing/tutorial004_py39.py hl[9:15,18,27:28,30:32,41:43] *}


You can read more details about the ["Running lifespan in tests in the official Starlette documentation site."](https://www.starlette.dev/lifespan/#running-lifespan-in-tests)

Do not suppress NullAway errors without a justification.
Prefer rearranging the code to avoid the error, unless there is a provable performance penalty or a significant loss of code readability.
Use `Objects.requireNonNull` statement or `Preconditions` rather than `assert` or `@SuppressWarning` annotation to suppress if possible.

For gradual adoption, enable checks project-by-project.
Do not rely on `@NullMarked` annotations.

    <module name="SuppressWarningsFilter"/>
    <module name="TreeWalker">
        <!-- Blocks -->
        <module name="EmptyBlock">
            <property name="option" value="statement"/>
            <property name="tokens" value="LITERAL_DO,LITERAL_ELSE,LITERAL_FINALLY,LITERAL_IF,LITERAL_FOR,LITERAL_TRY,LITERAL_WHILE,INSTANCE_INIT,STATIC_INIT"/>
        </module>
        <module name="EmptyBlock">

That converts the function into something called an "**async context manager**".

{* ../../docs_src/events/tutorial003_py39.py hl[1,13] *}

A **context manager** in Python is something that you can use in a `with` statement, for example, `open()` can be used as a context manager:

```Python
with open("file.txt") as file:
    file.read()
```