operationContext.setResult(Operation.Result.INSTANCE);
                return result;
            }

            @Override
            public BuildOperationDescriptor.Builder description() {
                return BuildOperationDescriptor
                    .displayName("Executing " + work.getDisplayName())
                    .details(new Operation.Details() {
                        @Override

                return buildOperationRunner.call(new CallableBuildOperation<T>() {
                    @Override
                    public BuildOperationDescriptor.Builder description() {
                        return BuildOperationDescriptor.displayName("Start deployment '" + name + "'");
                    }

                    @Override
                    public T call(BuildOperationContext context) {

    /**
     * Starts an operation that can be finished later.
     *
     * When a parent operation is finished any unfinished child operations will be failed.
     */
    BuildOperationContext start(BuildOperationDescriptor.Builder descriptor);

    /**
     * Executes the given build operation with the given worker, returns the result.
     */

                        deleter.deleteRecursively(file);
                    }
                }

                @Override
                public BuildOperationDescriptor.Builder description() {
                    return BuildOperationDescriptor
                        .displayName(CLEAN_STALE_OUTPUTS_DISPLAY_NAME)
                        .progressDisplayName("Cleaning stale outputs");
                }
            });

        }

        @Override
        public void started(BuildOperationDescriptor buildOperation, OperationStartEvent startEvent) {
            for (OperationResultPostProcessor processor : processors) {
                processor.started(buildOperation, startEvent);
            }
        }

        @Override
        public void finished(BuildOperationDescriptor buildOperation, OperationFinishEvent finishEvent) {

    }

    private OperationFinishEvent operationFinishEvent() {
        new OperationFinishEvent(123, 345, null, null)
    }

    private BuildOperationDescriptor descriptor() {
        new BuildOperationDescriptor(Stub(OperationIdentifier), null, "name", "name", "name", null, null, 12)
    }

    class MockBuildEventListenerFactory implements BuildEventListenerFactory {

                private final Map<String, Map<String, Object>> origins = [:]

                @Override
                void started($BuildOperationDescriptor.name buildOperation, $OperationStartEvent.name startEvent) {}

                @Override
                void finished($BuildOperationDescriptor.name buildOperation, $OperationFinishEvent.name finishEvent) {

import org.gradle.internal.execution.UnitOfWork;
import org.gradle.internal.execution.UnitOfWork.Identity;
import org.gradle.internal.fingerprint.CurrentFileCollectionFingerprint;
import org.gradle.internal.operations.BuildOperationDescriptor;
import org.gradle.internal.operations.BuildOperationRunner;
import org.gradle.internal.operations.BuildOperationType;
import org.gradle.internal.snapshot.ValueSnapshot;

import javax.annotation.Nonnull;

 *
 * @since 3.5
 */
@EventScope(Global.class)
public interface BuildOperationListener {

    void started(BuildOperationDescriptor buildOperation, OperationStartEvent startEvent);

    void progress(OperationIdentifier operationIdentifier, OperationProgressEvent progressEvent);

    void finished(BuildOperationDescriptor buildOperation, OperationFinishEvent finishEvent);

                });
                return result;
            }

            @Override
            public BuildOperationDescriptor.Builder description() {
                return BuildOperationDescriptor.displayName("Run nested build")
                    .details(new RunNestedBuildBuildOperationType.Details() {
                        @Override