Map.Entry<Artifact, Path> res = session.resolveArtifact(coord);
        assertNotNull(res);
        assertNotNull(res.getValue());
        assertTrue(Files.exists(res.getValue()));

        Node node = session.collectDependencies(session.createDependencyCoordinate(coord));
        assertNotNull(node);
        assertEquals(8, node.getChildren().size());
    }

        // System scoped version which should
        //
        d.setScope(Artifact.SCOPE_SYSTEM);
        File file = new File(getBasedir(), "src/test/repository-system/maven-core-2.1.0.jar");
        assertTrue(file.exists());
        d.setSystemPath(file.getCanonicalPath());

        artifact = repositorySystem.createDependencyArtifact(d);

        //

    public boolean isMerged() {
        return merged;
    }

    protected abstract void merge(Metadata recessive);

    static Metadata read(Path metadataPath) throws RepositoryException {
        if (!Files.exists(metadataPath)) {
            return Metadata.newInstance();
        }

        try (InputStream input = Files.newInputStream(metadataPath)) {
            return new MetadataStaxReader().read(input, false);

        requireNonNull(source, "source is null");
        requireNonNull(relativeTarget, "relativeTarget is null");
        if (Files.isRegularFile(source)) {
            throw new IllegalArgumentException("source file does not exist or is not a file");
        }
        if (relativeTarget.isAbsolute()) {
            throw new IllegalArgumentException("Supplied URI is not relative");
        }
        URI target = baseURI.resolve(relativeTarget);