go-version: [1.24.x]
        os: [ubuntu-latest]

    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-go@v5
        with:
          go-version: ${{ matrix.go-version }}
          check-latest: true
      - name: Start root lockdown tests
        run: |

本例把 `item_id` 的类型声明为 `int`。

/// check | 检查

类型声明将为函数提供错误检查、代码补全等编辑器支持。

///

## 数据<abbr title="也称为：序列化、解析">转换</abbr>

运行示例并访问 <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a>，返回的响应如下：

```JSON
{"item_id":3}
```

/// check | 检查

注意，函数接收并返回的值是 `3`（ `int`），不是 `"3"`（`str`）。

        }

        override fun nanoTime() = nanoTime

        override fun coordinatorNotify(taskRunner: TaskRunner) {
          taskRunner.assertLockHeld()
          check(waitingCoordinatorTask != null)

          // Queue a task to resume the waiting coordinator.
          serialTaskQueue +=
            object : SerialTask {
              override fun start() {

```hl_lines="4"
INFO:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

That line shows the URL where your app is being served, in your local machine.

### Check it { #check-it }

Open your browser at <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>.

You will see the JSON response as:

```JSON
{"message": "Hello World"}
```

    // as we cannot call it directly from the test.
    // This requires a package-private or public method in the class under test,
    // or we can just check for the prefix and suffix.
    // For this test, I'll add a helper in the response class to get super.toString()
    // Or, more simply, check the format of the string.
    @Test
    void testToStringFormat() {
        String str = response.toString();

@GwtCompatible
final class NullnessCasts {
  /**
   * Accepts a {@code @Nullable T} and returns a plain {@code T}, without performing any check that
   * that conversion is safe.
   *
   * <p>This method is intended to help with usages of type parameters that have {@linkplain

@GwtCompatible
final class NullnessCasts {
  /**
   * Accepts a {@code @Nullable T} and returns a plain {@code T}, without performing any check that
   * that conversion is safe.
   *
   * <p>This method is intended to help with usages of type parameters that have {@linkplain

## Available versions { #available-versions }

You can see the available versions (e.g. to check what is the current latest) in the [Release Notes](../release-notes.md){.internal-link target=_blank}.

## About versions { #about-versions }

/// info

Notice that `response_description` refers specifically to the response, the `description` refers to the *path operation* in general.

///

/// check

OpenAPI specifies that each *path operation* requires a response description.

So, if you don't provide one, **FastAPI** will automatically generate one of "Successful response".

///

    private val steps = BuildSteps()

    private val buildModel =
        CIBuildModel(
            projectId = "Gradle_Check",
            branch = VersionedSettingsBranch("master"),
            buildScanTags = listOf("Check"),
            subprojects = JsonBasedGradleSubprojectProvider(File("../.teamcity/subprojects.json")),
        )

    @BeforeEach
    fun setUp() {
        val stepsCapturer = slot<BuildSteps.() -> Unit>()