You can use the `TestClient` class to test FastAPI applications without creating an actual HTTP and socket connection, just communicating directly with the FastAPI code.

Read more about it in the [FastAPI docs for Testing](https://fastapi.tiangolo.com/tutorial/testing/).

You can import it directly from `fastapi.testclient`:

```python
from fastapi.testclient import TestClient
```

from starlette.testclient import TestClient as TestClient  # noqa...

):
    return ItemOut(name="foo", value=123, dep=dep)


@pytest.fixture(scope="module")
def client() -> Iterator[TestClient]:
    with TestClient(app) as client:
        yield client


def _bench_get(benchmark, client: TestClient, path: str) -> tuple[int, bytes]:
    warmup = client.get(path)
    assert warmup.status_code == 200

    def do_request() -> tuple[int, bytes]:

from typing import Annotated

import pytest
from fastapi import FastAPI, Form
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

from .utils import get_body_model_name

app = FastAPI()

# =====================================================================================
# Without aliases


@app.post("/optional-list-str", operation_id="optional_list_str")
async def read_optional_list_str(

import importlib

import pytest
from dirty_equals import IsList
from fastapi.testclient import TestClient
from inline_snapshot import snapshot

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial005_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.body_nested_models.{request.param}")

"""

from typing import Annotated

from fastapi import BackgroundTasks, Depends, FastAPI, Request, Response
from fastapi.responses import JSONResponse
from fastapi.testclient import TestClient


def test_response_with_depends_annotated():
    """Response type hint should work with Annotated[Response, Depends(...)]."""
    app = FastAPI()

    def modify_response(response: Response) -> Response:

@pytest.fixture(name="client")
def client_fixture() -> TestClient:
    app = FastAPI()

    @app.get("/")
    async def get_people(client: Client) -> list:
        return await client.get_people()

    client = TestClient(app)
    return client


def test_get(client: TestClient):
    response = client.get("/")
    assert response.status_code == 200, response.text

    async def read_root() -> Any:
        return {"$ref": "some-ref"}

    client = TestClient(app)
    return client


def test_get(client: TestClient):
    response = client.get("/")
    assert response.json() == {"$ref": "some-ref"}


def test_openapi_schema(client: TestClient):
    response = client.get("openapi.json")
    assert response.json() == snapshot(
        {

import pytest
from fastapi import FastAPI
from fastapi.testclient import TestClient
from inline_snapshot import snapshot


@pytest.fixture(name="client")
def get_client(request):
    separate_input_output_schemas = request.param
    app = FastAPI(separate_input_output_schemas=separate_input_output_schemas)

    from pydantic import BaseModel, computed_field

    class Rectangle(BaseModel):
        width: int
        length: int

import warnings

import pytest
from fastapi import FastAPI
from fastapi.exceptions import FastAPIDeprecationWarning
from fastapi.responses import ORJSONResponse, UJSONResponse
from fastapi.testclient import TestClient
from pydantic import BaseModel


class Item(BaseModel):
    name: str
    price: float


# ORJSON


def _make_orjson_app() -> FastAPI:
    with warnings.catch_warnings():