}

    @Nonnull
    @Override
    public Collection<ProducedArtifact> getAttachedArtifacts(@Nonnull Project project) {
        requireNonNull(project, "project" + " cannot be null");
        Collection<ProducedArtifact> attached =
                map(getMavenProject(project).getAttachedArtifacts(), a -> getSession(project)
                        .getArtifact(ProducedArtifact.class, RepositoryUtils.toArtifact(a)));

                        "pom".equals(project.getPackaging()) ? Stream.empty() : Stream.of(project.getArtifact())),
                // attached artifacts
                project.getAttachedArtifacts().stream());
        return artifacts.map(RepositoryUtils::toArtifact);
    }

    private boolean isRegularFile(Artifact artifact) {
        return artifact.getFile() != null && artifact.getFile().isFile();