private val forbiddenLocks = mutableListOf<Any>()

  /** The timestamp of the last taken event, used to measure elapsed time between events. */
  private var lastTimestampNs: Long? = null

  /** Confirm that the thread does not hold a lock on `lock` during the callback. */
  fun forbidLock(lock: Any) {
    forbiddenLocks.add(lock)
  }

  /**

      assertThat(response.code).isEqualTo(200)
      assertThat(response.socket).isNull()
      assertThat(response.body.string()).isEqualTo("normal request")
    }
    // Confirm there's no RequestBodyStart/RequestBodyEnd on failed upgrades.
    assertThat(eventRecorder.recordedEventTypes()).containsExactly(
      CallStart::class,
      ProxySelectStart::class,
      ProxySelectEnd::class,

        file("/build/restResources/yamlTests/rest-api-spec/test/" + coreTest).exists()
        file("/build/restResources/yamlTests/rest-api-spec/test/" + xpackTest).exists()

        // confirm that replacement happened
        file("/build/restResources/yamlTests/rest-api-spec/test/" + coreTest).getText("UTF-8") == "replacedWithValue"

        when:
        result = gradleRunner("copyRestApiSpecsTask").build()

...then the `description` field will **not be required**. Because it has a default value of `None`.

### Input Model in Docs { #input-model-in-docs }

You can confirm that in the docs, the `description` field doesn't have a **red asterisk**, it's not marked as required:

<div class="screenshot">
<img src="/img/tutorial/separate-openapi-schemas/image01.png">
</div>

    taskRunner.withLock {
      check(currentTask == TestThreadSerialTask)
      nanoTime = newTime
      yieldUntil(ResumePriority.AfterOtherTasks)
    }
  }

  /** Confirm all tasks have completed. Used by the test thread only. */
  fun assertNoMoreTasks() {
    taskRunner.assertLockNotHeld()

    taskRunner.withLock {
      assertThat(activeThreads).isEqualTo(0)
    }
  }

    routeSelector = newRouteSelector(address)

    // Confirm we enumerate both proxies, giving preference to the route from ProxyB.
    val selection2 = routeSelector.next()
    dns.assertRequests(PROXY_A_HOST, PROXY_B_HOST)
    assertRoute(selection2.next(), address, proxyB, dns.lookup(PROXY_B_HOST, 0), PROXY_B_PORT)
    assertThat(selection2.hasNext()).isFalse()

    // Confirm the last selection contains the postponed route from ProxyA.

    /*
     * We need to wait for the runner to exit. It used to be that the runner would get stuck in the
     * busy loop when interrupt threw.
     *
     * While we're at it, we confirm that the interrupt happened as expected.
     */
    ExecutionException fromRunInterruptibly =
        assertThrows(ExecutionException.class, () -> taskResult.get(10, SECONDS));

    /*
     * We need to wait for the runner to exit. It used to be that the runner would get stuck in the
     * busy loop when interrupt threw.
     *
     * While we're at it, we confirm that the interrupt happened as expected.
     */
    ExecutionException fromRunInterruptibly =
        assertThrows(ExecutionException.class, () -> taskResult.get(10, SECONDS));

    } catch (ioe: IOException) {
      assertThat(ioe).hasMessage("google.com")
      assertThat(ioe.cause!!).isInstanceOf<EOFException>()
    }
  }

  // TODO GET preferred order - with tests to confirm this
  // 1. successful fresh cached GET response
  // 2. unsuccessful (404, 500) fresh cached GET response
  // 3. successful network response
  // 4. successful stale cached GET response
  // 5. unsuccessful response

  - type: checkboxes
    id: checks
    attributes:
      label: First Check
      description: Please confirm and check all the following options.
      options:
        - label: I added a very descriptive title here.
          required: true
        - label: I used the GitHub search to find a similar question and didn't find it.