}
        return null;
    }

    @Nonnull
    public static Path findMandatoryRoot(Path topDirectory) {
        requireNonNull(topDirectory, "topDirectory");
        return getCanonicalPath(Optional.ofNullable(
                        ServiceLoader.load(RootLocator.class).iterator().next().findMandatoryRoot(topDirectory))
                .orElseThrow());
    }

            }

            // project present, but we could not determine rootDirectory: extra work needed
            if (context.invokerRequest.rootDirectory().isEmpty()) {
                Path rootDirectory = CliUtils.findMandatoryRoot(context.invokerRequest.topDirectory());
                request.setMultiModuleProjectDirectory(rootDirectory.toFile());
                request.setRootDirectory(rootDirectory);
            }
        }