}
                }),
            executor);

    // Pause in step 2.
    step2Waiter.awaitStarted();

    // Everything should still be open.
    assertStillOpen(closeable1, closeable2, closeable3, closeable4);

    // Cancel step 3, resume step 2, and pause in step 4.
    assertWithMessage("step3.cancel()").that(step3.cancel(false)).isTrue();
    step2Waiter.awaitReturned();

                  }
                }),
            executor);

    // Pause in step 2.
    step2Waiter.awaitStarted();

    // Everything should still be open.
    assertStillOpen(closeable1, closeable2, closeable3, closeable4);

    // Cancel step 3, resume step 2, and pause in step 4.
    assertWithMessage("step3.cancel()").that(step3.cancel(false)).isTrue();
    step2Waiter.awaitReturned();

    }

    /**
     * Unravels trace tree (going upwards from current node), looking for {@link CollectStepData} trace data.
     * This method may return {@code null} if no collect step data found in passed trace data or it's parents.
     * <p>
     * Visible for testing.
     */
    static CollectStepData lookupCollectStepData(RequestTrace trace) {
        CollectStepData collectStepTrace = null;

   *
   * <p>In JUnit4 language, that means as an {@code @After}.
   *
   * <p>In JUnit3 language, that means during the {@link junit.framework.TestCase#tearDown()} step.
   */
  void addTearDown(TearDown tearDown);

         * Only kill local Gradle processes (classpath in checkout directory).
         * Not clean up global Gradle processes (i.e. classpath in ~/.gradle/...).
         * Because the step is not guaranteed to run (e.g. build timeout), we need `KILL_LEAKED_PROCESSES_FROM_PREVIOUS_BUILDS` mode.
         */
        KILL_PROCESSES_STARTED_BY_GRADLE,
        /**

        }

        return delegate.calculateLifecycleMappings(session, project, lifecycle, lifecyclePhase);
    }

    /**
     * Post-processes the effective configuration for the specified mojo execution. This step discards all parameters
     * from the configuration that are not applicable to the mojo and injects the default values for any missing
     * parameters.
     *

   *       pending tasks and interrupting running tasks.
   *   <li>awaits executor service termination for the other half of the specified timeout.
   * </ol>
   *
   * <p>If, at any step of the process, the calling thread is interrupted, the method calls {@link
   * ExecutorService#shutdownNow()} and returns.
   *
   * @param service the {@code ExecutorService} to shut down

                || mojoExecution.getConfiguration().getChildCount() == 0) {
            return;
        }

        MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();

        // in first step get parameter names of current goal
        Set<String> parametersNamesGoal = mojoDescriptor.getParameters().stream()
                .flatMap(this::getParameterNames)
                .collect(Collectors.toSet());

 * is by declaring that step to be the last step of the pipeline. Nevertheless, we refer to the
 * "value" of a successful step or the "result" (value or exception) of any step.
 *
 * <ol>
 *   <li>A pipeline starts at its leaf step (or steps), which is created from either a callable
 *       block or a {@link ListenableFuture}.

        ArrayReference<? extends L> arrayRef = (ArrayReference<? extends L>) ref;
        // Try to clear out the array slot, n.b. if we fail that is fine, in either case the
        // arrayRef will be out of the array after this step.
        locks.compareAndSet(arrayRef.index, arrayRef, null);
      }
    }

    @Override
    public int size() {
      return size;
    }