public T apply(T key) {
      awaitUninterruptibly(delayLatch);
      return key;
    }
  }

  /*
   * TODO(cpovirk): eliminate duplication between these tests and those in LegacyMapMakerTests and
   * anywhere else
   */

  public void testInitialCapacity_negative() {
    MapMaker maker = new MapMaker();
    assertThrows(IllegalArgumentException.class, () -> maker.initialCapacity(-1));
  }

And then **FastAPI** will call that override instead of the original dependency.

{* ../../docs_src/dependency_testing/tutorial001_an_py310.py hl[26:27,30] *}

/// tip

You can set a dependency override for a dependency used anywhere in your **FastAPI** application.

The original dependency could be used in a *path operation function*, a *path operation decorator* (when you don't use the return value), a `.include_router()` call, etc.

As the testing function is now asynchronous, you can now also call (and `await`) other `async` functions apart from sending requests to your FastAPI application in your tests, exactly as you would call them anywhere else in your code.

/// tip

Let's make it give us the current user.

## Create a user model { #create-a-user-model }

First, let's create a Pydantic user model.

The same way we use Pydantic to declare bodies, we can use it anywhere else:

{* ../../docs_src/security/tutorial002_an_py310.py hl[5,12:6] *}

## Create a `get_current_user` dependency { #create-a-get-current-user-dependency }

Let's create a dependency `get_current_user`.

- Temporary credentials are short-term, as the name implies. They can be configured to last for anywhere from a few minutes to several hours. After the credentials expire, MinIO no longer recognizes them or allows any kind of access from API requests made with them.

* Generate <a href="https://json-schema.org" class="external-link" target="_blank">JSON Schema</a> definitions for your model, you can also use them anywhere else you like if it makes sense for your project.
* Those schemas will be part of the generated OpenAPI schema, and used by the automatic documentation <abbr title="User Interfaces">UIs</abbr>.

## Automatic docs { #automatic-docs }

But the client/user will not see it. Instead, the client will receive an "Internal Server Error" with an HTTP status code `500`.

It should be this way because if you have a Pydantic `ValidationError` in your *response* or anywhere in your code (not in the client's *request*), it's actually a bug in your code.

And while you fix it, your clients/users shouldn't have access to internal information about the error, as that could expose a security vulnerability.

/// tip

We'll discuss the `@lru_cache` in a bit.

For now you can assume `get_settings()` is a normal function.

///

And then we can require it from the *path operation function* as a dependency and use it anywhere we need it.

{* ../../docs_src/settings/app02_an_py39/main.py hl[17,19:21] *}

### Settings and testing { #settings-and-testing }

  public void testScanFromFile_fileNotExists() throws IOException {
    ClassLoader classLoader = ClassPathTest.class.getClassLoader();
    assertThat(
            new ClassPath.LocationInfo(new File("no/such/file/anywhere"), classLoader)
                .scanResources())
        .isEmpty();
  }

  @AndroidIncompatible // ClassPath is documented as not supporting Android

  @InlineMe(replacement = "Character.compare(a, b)")
  public static int compare(char a, char b) {
    return Character.compare(a, b);
  }

  /**
   * Returns {@code true} if {@code target} is present as an element anywhere in {@code array}.
   *
   * @param array an array of {@code char} values, possibly empty
   * @param target a primitive {@code char} value
   * @return {@code true} if {@code array[i] == target} for some value of {@code i}