this.topologicallySortedProjects = topologicallySortedProjects;

        return this;
    }

    @Override
    public List<MavenProject> getTopologicallySortedProjects() {
        return null == topologicallySortedProjects
                ? Collections.emptyList()
                : Collections.unmodifiableList(topologicallySortedProjects);
    }

    @Override

        MavenExecutionResult result = new DefaultMavenExecutionResult();
        result.setTopologicallySortedProjects(null);
        List<MavenProject> projects = result.getTopologicallySortedProjects();
        assertNotNull(projects);
        assertTrue(
                projects.isEmpty(),
                "Expected collection to be empty but had " + projects.size() + " elements: " + projects);
    }

    MavenExecutionResult setTopologicallySortedProjects(List<MavenProject> projects);

    /**
     * @return the sorted list, or an empty list if there are no projects.
     */
    List<MavenProject> getTopologicallySortedProjects();

    MavenExecutionResult setDependencyResolutionResult(DependencyResolutionResult result);

    DependencyResolutionResult getDependencyResolutionResult();

    // for each exception

        if (!result.hasExceptions()) {
            return Optional.empty();
        }

        List<MavenProject> sortedProjects = result.getTopologicallySortedProjects();

        boolean hasNoSuccess =
                sortedProjects.stream().noneMatch(project -> result.getBuildSummary(project) instanceof BuildSuccess);

        if (hasNoSuccess) {

        assertFalse(result.hasExceptions(), result.getExceptions().toString());

        List<String> order = new ArrayList<>();
        for (MavenProject project : result.getTopologicallySortedProjects()) {
            order.add(project.getArtifactId());
        }
        return order;
    }