=== "Python 3.10+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an_py310/main.py!}
    ```

=== "Python 3.9+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an_py39/main.py!}
    ```

=== "Python 3.8+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an/main.py!}
    ```

=== "Python 3.10+ без Annotated"

    !!! tip "Подсказка"

=== "Python 3.10+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an_py310/main.py!}
    ```

=== "Python 3.9+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an_py39/main.py!}
    ```

=== "Python 3.8+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an/main.py!}
    ```

=== "Python 3.10+ non-Annotated"

    !!! tip

所有*路径操作* 都需要一个`X-Token` 头。

=== "Python 3.10+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an_py310/main.py!}
    ```

=== "Python 3.9+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an_py39/main.py!}
    ```

=== "Python 3.8+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an/main.py!}
    ```

=== "Python 3.10+ non-Annotated"

    !!! tip "提示"

=== "🐍 3️⃣.6️⃣ & 🔛"

    ```Python
    {!> ../../../docs_src/app_testing/app_b/main.py!}
    ```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_py310/main.py!}
    ```

### ↔ 🔬 📁

👆 💪 ⤴️ ℹ `test_main.py` ⏮️ ↔ 💯:

```Python
{!> ../../../docs_src/app_testing/app_b/test_main.py!}
```

=== "Python 3.10+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an_py310/main.py!}
    ```

=== "Python 3.9+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an_py39/main.py!}
    ```

=== "Python 3.8+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an/main.py!}
    ```

=== "Python 3.10+ nicht annotiert"

    !!! tip "Tipp"

You could want to set up a different database for testing, rollback the data after the tests, pre-fill it with some testing data, etc.

The main idea is exactly the same you saw in that previous chapter.

## Add tests for the SQL app

# 测试 WebSockets

测试 WebSockets 也使用 `TestClient`。

为此，要在 `with` 语句中使用 `TestClient` 连接 WebSocket。

```Python hl_lines="27-31"
{!../../../docs_src/app_testing/tutorial002.py!}
```

!!! note "笔记"

对于这些用例，**FastAPI** 应用支持 `app.dependcy_overrides` 属性，该属性就是**字典**。

要在测试时覆盖原有依赖项，这个字典的键应当是原依赖项（函数），值是覆盖依赖项（另一个函数）。

这样一来，**FastAPI** 就会调用覆盖依赖项，不再调用原依赖项。

```Python hl_lines="26-27  30"
{!../../../docs_src/dependency_testing/tutorial001.py!}
```

!!! tip "提示"

    **FastAPI** 应用中的任何位置都可以实现覆盖依赖项。

    原依赖项可用于*路径操作函数*、*路径操作装饰器*（不需要返回值时）、`.include_router()` 调用等。

    FastAPI 可以覆盖这些位置的依赖项。

# Testing Dependencies with Overrides

## Overriding dependencies during testing

There are some scenarios where you might want to override a dependency during testing.

You don't want the original dependency to run (nor any of the sub-dependencies it might have).

```Python hl_lines="27-31"
{!../../../docs_src/app_testing/tutorial002.py!}
```

!!! note "Hinweis"