public void testCustomEscaper_withpercent() {
    UnicodeEscaper e = new PercentEscaper("%", false);
    assertEquals("foo%7Cbar", e.escape("foo|bar"));
    assertEquals("foo%7Cbar", e.escape("foo%7Cbar")); // idempotent
  }

  /** Test that giving a null 'safeChars' string causes a {@link NullPointerException}. */
  public void testBadArguments_null() {

app = FastAPI()


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: float = 10.5
    tags: list[str] = []


items = {
    "foo": {"name": "Foo", "price": 50.2},
    "bar": {"name": "Bar", "description": "The bartenders", "price": 62, "tax": 20.2},
    "baz": {"name": "Baz", "description": None, "price": 50.2, "tax": 10.5, "tags": []},
}

KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
-->

<project>
  <modelVersion>4.0.0</modelVersion>
  <artifactId>foo</artifactId>
  <groupId>foo</groupId>
  <version>99.44</version>
  <packaging>bleh</packaging>
  <reporting>
    <plugins>
      <plugin>

      </plugin>
    </plugins>
  </reporting>

KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
-->

<project>
  <modelVersion>4.0.0</modelVersion>
  <artifactId>foo</artifactId>
  <groupId>foo</groupId>
  <version>99.44</version>
  <packaging>bleh</packaging>

  <modules>
    <module>test-module</module>
  </modules>

KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
-->

<project>
  <groupId>foo</groupId>
  <artifactId>foo</artifactId>
  <version>99.44</version>
  <packaging>bleh</packaging>

////

In this case **FastAPI** will expect a body like:

```JSON hl_lines="2"
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    }
}
```

instead of:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2
}
```

## Recap

////

In diesem Fall erwartet **FastAPI** einen Body wie:

```JSON hl_lines="2"
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    }
}
```

statt:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2
}
```

## Zusammenfassung

    client = TestClient(app)
    return client


def test_items_5(client: TestClient):
    response = client.put("/items/5", json={"item": {"name": "Foo", "price": 3.0}})
    assert response.status_code == 200
    assert response.json() == {
        "item_id": 5,
        "item": {"name": "Foo", "price": 3.0, "description": None, "tax": None},
    }


def test_items_6(client: TestClient):
    response = client.put(
        "/items/6",

    return client


@needs_py39
def test_items_5(client: TestClient):
    response = client.put("/items/5", json={"item": {"name": "Foo", "price": 3.0}})
    assert response.status_code == 200
    assert response.json() == {
        "item_id": 5,
        "item": {"name": "Foo", "price": 3.0, "description": None, "tax": None},
    }


@needs_py39
def test_items_6(client: TestClient):
    response = client.put(

item: Item = Body(..., embed=True)
```

이 경우에 **FastAPI**는 본문을 아래 대신에:

```JSON hl_lines="2"
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2
}
```

아래 처럼 예측할 것 입니다:

```JSON
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    }
}
```

## 정리