DefaultResolvedDependency parent1 = new DefaultResolvedDependency("p1", newId("someGroup", "someChild", "someVersion"), buildOperationProcessor)
        parent1.addChild(resolvedDependency)

        DefaultResolvedDependency parent2 = new DefaultResolvedDependency("p2", newId("someGroup", "someChild", "someVersion"), buildOperationProcessor)
        parent2.addChild(resolvedDependency)

        def parent1 = Mock(ParentServices)
        def parent2 = Mock(ParentServices)
        def registry = new DefaultServiceRegistry(registry(parent1), registry(parent2))

        when:
        def result = registry.get(BigDecimal)

        then:
        result == value

        and:
        1 * parent1.get(BigDecimal) >> null
        1 * parent2.get(BigDecimal) >> value
    }

        collectOwnStrictVersions(parent1, ['b', 'c'])
        collectOwnStrictVersions(parent2, ['b', 'd'])

        def child = nextNode()
        def edge1 = edge(parent1, false, null, child)
        def edge2 = edge(parent2, false, null, child)
        parent1.collectAncestorsStrictVersions([parent1Edge])
        parent2.collectAncestorsStrictVersions([parent2Edge])

    }

    public MultiParentClassLoader(ClassLoader... parents) {
        this(Arrays.asList(parents));
    }

    public MultiParentClassLoader(Collection<? extends ClassLoader> parents) {
        super(null);
        this.parents = new CopyOnWriteArrayList<ClassLoader>(parents);
    }

    public void addParent(ClassLoader parent) {
        parents.add(parent);
    }

    public List<ClassLoader> getParents() {

            is KtWhenCondition ->
                doesParentUseChild(parent.parent, parent)

            // Type parameters, return types and other annotations are all contained in KtUserType,
            // and are never considered used as expressions
            is KtUserType ->
                false

        if (spec instanceof SystemClassLoaderSpec) {
            return rootClassLoader;
        }
        if (spec instanceof MultiParentClassLoader.Spec) {
            return new MultiParentClassLoader(parents);
        }
        if (parents.size() != 1) {
            throw new IllegalArgumentException("Expected a single parent.");
        }
        ClassLoader parent = parents.get(0);

    }

    private ResolvedArtifactSet getArtifactsForIncomingEdge(DependencyGraphNodeResult parent) {
        if (!parents.contains(parent)) {
            throw new InvalidUserDataException("Provided dependency (" + parent + ") must be a parent of: " + this);
        }
        return CompositeResolvedArtifactSet.of(parentArtifacts.get((ResolvedDependency) parent));
    }

    @Override

        return this;
    }

    public ServiceRegistry build() {
        ServiceRegistry[] parents = this.parents.toArray(new ServiceRegistry[0]);

        DefaultServiceRegistry registry = scope != null
            ? new ScopedServiceRegistry(scope, strict, displayName, parents)
            : new DefaultServiceRegistry(displayName, parents);

        for (ServiceRegistrationProvider provider : providers) {

    public ClassLoader getClassLoaderFor(ClassLoaderSpec spec, List<? extends ClassLoader> parents) {
        if (spec instanceof VisitableURLClassLoader.Spec) {
            VisitableURLClassLoader.Spec clSpec = (VisitableURLClassLoader.Spec) spec;
            if (parents.size() != 1) {
                throw new IllegalStateException("Expected exactly one parent ClassLoader");
            }

        ServiceRegistry... parents
    ) {
        ServiceRegistryBuilder builder = ServiceRegistryBuilder.builder()
            .scopeStrictly(Scope.Global.class)
            .displayName("Global services")
            .provider(new GlobalScopeServices(longLiving, agentStatus, additionalModuleClassPath))
            .provider(new BuildProcessScopeServices());
        for (ServiceRegistry parent : parents) {