`TestClient` 是基于 <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a> 的。幸运的是，我们可以直接使用它来测试API。

## 示例

举个简单的例子，让我们来看一个[更大的应用](../tutorial/bigger-applications.md){.internal-link target=_blank}和[测试](../tutorial/testing.md){.internal-link target=_blank}中描述的类似文件结构：

```
.
├── app
│   ├── __init__.py
│   ├── main.py
│   └── test_main.py
```

     * <ul>
     *     <li>System properties (lowest precedence)</li>
     *     <li>Project properties (optional)</li>
     *     <li>User properties (highest precedence)</li>
     * </ul>
     * Note: Project properties contains properties injected from profiles, if applicable. Their precedence is

     * method returns {@code true}, it means that element count of stream returned by method {@link #problems()}
     * and the counter returned by {@link #totalProblemsReported()} are not equal (latter is bigger than former).
     *
     * @return true if the problem collector has overflowed and some problems were not preserved
     */
    boolean problemsOverflow();

    /**

func TestMaxPartID(t *testing.T) {
	sizes := []struct {
		isMax bool
		partN int
	}{
		// Test - 1 part number within max part number.
		{
			false,
			globalMaxPartID - 1,
		},
		// Test - 2 part number bigger than max part number.
		{
			true,
			globalMaxPartID + 1,
		},
	}

	for i, s := range sizes {
		isMax := isMaxPartID(s.partN)
		if isMax != s.isMax {

Y tu aplicación de **FastAPI** también podría estar compuesta de varios archivos/módulos, etc.

### Archivo de aplicación **FastAPI**

Digamos que tienes una estructura de archivos como se describe en [Aplicaciones Más Grandes](bigger-applications.md){.internal-link target=_blank}:

```
.
├── app
│   ├── __init__.py
│   └── main.py
```

En el archivo `main.py` tienes tu aplicación de **FastAPI**:

            public String getIndexFieldCreated() {
                return "created";
            }

            @Override
            public String getIndexFieldDigest() {
                return "digest";
            }

            @Override
            public String getIndexFieldThumbnail() {
                return "thumbnail";
            }

            @Override

    /**
     * Returns the execution type identifier for this job.
     * This type is used for classpath construction, configuration, and logging purposes.
     *
     * @return the execution type (e.g., "crawler", "suggest", etc.)
     */
    protected abstract String getExecuteType();

    /**
     * Executes the job with the specified job executor.
     * This method sets the job executor and then calls the abstract execute method.

@NullUnmarked
public class PopulatedCachesTest extends TestCase {
  // we use integers as keys; make sure the range covers some values that ARE cached by
  // Integer.valueOf(int), and some that are not cached. (127 is the highest cached value.)
  static final int WARMUP_MIN = 120;
  static final int WARMUP_MAX = 135;
  static final int WARMUP_SIZE = WARMUP_MAX - WARMUP_MIN;

  public void testSize_populated() {

     * list of filters to apply. By default, no version filter is applied (like in Maven 3).
     * <br/>
     * Supported filters:
     * <ul>
     *     <li>"h" or "h(num)" - highest version or top list of highest ones filter</li>
     *     <li>"l" or "l(num)" - lowest version or bottom list of lowest ones filter</li>
     *     <li>"s" - contextual snapshot filter</li>

// lineTooLong is generated as chunk header is bigger than 4KiB.
var errLineTooLong = errors.New("header line too long")

// malformed encoding is generated when chunk header is wrongly formed.
var errMalformedEncoding = errors.New("malformed chunked encoding")

// chunk is considered too big if its bigger than > 16MiB.
var errChunkTooBig = errors.New("chunk too big: choose chunk size <= 16MiB")