<type>String</type>
          <defaultValue><![CDATA[]]></defaultValue>
          <description><![CDATA[If specified, identifies this phase as a dynamic phase to decorate the specified phase id, e.g. {@code after} or {@code before}.]]></description>
        </field>
        <field xml.attribute="true">
          <name>priority</name>
          <required>false</required>
          <version>2.0.0+</version>
          <type>int</type>

{* ../../docs_src/async_tests/test_main.py hl[7] *}

/// tip

Note that the test function is now `async def` instead of just `def` as before when using the `TestClient`.

///

Then we can create an `AsyncClient` with the app, and send async requests to it, using `await`.

{* ../../docs_src/async_tests/test_main.py hl[9:12] *}

  private val listener = EventSourceRecorder()
  private var client =
    clientTestRule.newClientBuilder()
      .eventListenerFactory(clientTestRule.wrap(eventListener))
      .build()

  @BeforeEach
  fun before(server: MockWebServer) {
    this.server = server
  }

  @AfterEach
  fun after() {
    listener.assertExhausted()
  }

  @Test
  fun event() {
    server.enqueue(
      MockResponse.Builder()

 *   <li>NullAway, which will <a
 *       href="https://github.com/google/guava/issues/6126#issuecomment-1204399671">treat it
 *       identically to {@code Nullable} as of version 0.9.9</a>. To treat it that way before then,
 *       you can set {@code
 *       -XepOpt:NullAway:CustomNullableAnnotations=com.google.common.base.ParametricNullness,...,com.google.common.util.concurrent.ParametricNullness},

   * the entry was returned by the iterator, except through the setValue operation on the map entry"
   * As such, this field must be cleared before every map mutation.
   *
   * Note about volatile: volatile doesn't make it safe to read from a mutable graph in one thread
   * while writing to it in another. All it does is help with _reading_ from multiple threads

 *   <li>NullAway, which will <a
 *       href="https://github.com/google/guava/issues/6126#issuecomment-1204399671">treat it
 *       identically to {@code Nullable} as of version 0.9.9</a>. To treat it that way before then,
 *       you can set {@code
 *       -XepOpt:NullAway:CustomNullableAnnotations=com.google.common.base.ParametricNullness,...,com.google.common.util.concurrent.ParametricNullness},

 *   <li>NullAway, which will <a
 *       href="https://github.com/google/guava/issues/6126#issuecomment-1204399671">treat it
 *       identically to {@code Nullable} as of version 0.9.9</a>. To treat it that way before then,
 *       you can set {@code
 *       -XepOpt:NullAway:CustomNullableAnnotations=com.google.common.base.ParametricNullness,...,com.google.common.util.concurrent.ParametricNullness},

 *   <li>NullAway, which will <a
 *       href="https://github.com/google/guava/issues/6126#issuecomment-1204399671">treat it
 *       identically to {@code Nullable} as of version 0.9.9</a>. To treat it that way before then,
 *       you can set {@code
 *       -XepOpt:NullAway:CustomNullableAnnotations=com.google.common.base.ParametricNullness,...,com.google.common.util.concurrent.ParametricNullness},

 *   <li>NullAway, which will <a
 *       href="https://github.com/google/guava/issues/6126#issuecomment-1204399671">treat it
 *       identically to {@code Nullable} as of version 0.9.9</a>. To treat it that way before then,
 *       you can set {@code
 *       -XepOpt:NullAway:CustomNullableAnnotations=com.google.common.base.ParametricNullness,...,com.google.common.util.concurrent.ParametricNullness},

   * index n is done, the output future at index n-1 is also done. (But as usual with futures, some
   * listeners for future n may complete before some for future n-1.) However, it is possible, if
   * one input completes with result X and another later with result Y, for Y to come before X in
   * the output future list. (Such races are impossible to solve without global synchronization of