var wr = NewWriter(writeErrorOnlyWriter{})
	s := "test1"
	wantBuffered := len(s)
	if _, err := wr.WriteString(s); err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if err := wr.Flush(); err == nil {
		t.Error("expected flush error, got nil")
	}
	if _, err := wr.ReadFrom(strings.NewReader("test2")); err == nil {
		t.Fatal("expected error, got nil")
	}

test3...

test3...

test.txt This is a test text file. gophercolor16x16.png...

test.jpg...

# Tests Asíncronos

Ya has visto cómo probar tus aplicaciones de **FastAPI** usando el `TestClient` proporcionado. Hasta ahora, solo has visto cómo escribir tests sincrónicos, sin usar funciones `async`.

Vamos ver como nós podemos fazer isso funcionar.

## pytest.mark.anyio

Se quisermos chamar funções assíncronas em nossos testes, as nossas funções de teste precisam ser assíncronas. O AnyIO oferece um plugin bem legal para isso, que nos permite especificar que algumas das nossas funções de teste precisam ser chamadas de forma assíncrona.

## HTTPX

# Async Tests { #async-tests }

You have already seen how to test your **FastAPI** applications using the provided `TestClient`. Up to now, you have only seen how to write synchronous tests, without using `async` functions.

# Asynchrone Tests

Sie haben bereits gesehen, wie Sie Ihre **FastAPI**-Anwendungen mit dem bereitgestellten `TestClient` testen. Bisher haben Sie nur gesehen, wie man synchrone Tests schreibt, ohne `async`hrone Funktionen zu verwenden.

    validations:
      required: true

  - type: textarea
    id: tests
    attributes:
      label: Which tests are flaking?
    validations:
      required: true

  - type: textarea
    id: since
    attributes:
      label: Since when has it been flaking?
    validations: