CompositeDomainObjectSet<T> out = new CompositeDomainObjectSet<T>(delegate, callbackActionDecorator);
        for (DomainObjectCollection<? extends T> c : collections) {
            out.addCollection(c);
        }
        return out;
    }

    private CompositeDomainObjectSet(DefaultDomainObjectSet<T> delegate, CollectionCallbackActionDecorator callbackActionDecorator) {

    <T> NamedDomainObjectList<T> newNamedDomainObjectList(Class<T> elementType);

    /**
     * Creates a {@link CompositeDomainObjectSet} for managing a collection of {@link DomainObjectCollection} of the specified type.
     */
    <T> CompositeDomainObjectSet<T> newDomainObjectSet(Class<T> elementType, DomainObjectCollection<? extends T> collection);

    }

    @Override
    public <T> CompositeDomainObjectSet<T> newDomainObjectSet(Class<T> elementType, DomainObjectCollection<? extends T> collection) {
        return CompositeDomainObjectSet.create(elementType, collectionCallbackActionDecorator, collection);
    }

 * limitations under the License.
 */

package org.gradle.api.publish.internal;

import org.gradle.api.file.FileCollection;
import org.gradle.api.internal.CompositeDomainObjectSet;
import org.gradle.api.internal.DelegatingDomainObjectSet;
import org.gradle.api.internal.file.FileCollectionInternal;
import org.gradle.api.internal.file.UnionFileCollection;

        def c1 = new DefaultDomainObjectSet<String>(String, callbackActionDecorator)
        def c2 = new DefaultDomainObjectSet<String>(String, callbackActionDecorator)
        given:
        def composite = CompositeDomainObjectSet.<String>create(String, c1, c2)
        def set = new DefaultDomainObjectSet<String>(String, composite.getStore(), callbackActionDecorator)

        when:
        c1.add("a")
        c1.add("b")

import org.gradle.api.component.SoftwareComponent;
import org.gradle.api.file.Directory;
import org.gradle.api.internal.CollectionCallbackActionDecorator;
import org.gradle.api.internal.CompositeDomainObjectSet;
import org.gradle.api.internal.artifacts.DefaultModuleVersionIdentifier;
import org.gradle.api.internal.artifacts.Module;
import org.gradle.api.internal.artifacts.configurations.DependencyMetaDataProvider;

        entries.each { collection.add(it) }
        collection
    }

    protected composite(DomainObjectCollection... collections) {
        CompositeDomainObjectSet.create(type, *collections)
    }

    def "empty composite contains no elements"() {
        expect:
        composite().empty
    }

    def "composite containing one collection"() {
        expect:

    private final CalculatedValueContainerFactory calculatedValueContainerFactory;
    private final ProjectStateRegistry projectStateRegistry;
    private CompositeDomainObjectSet<Dependency> inheritedDependencies;
    private CompositeDomainObjectSet<DependencyConstraint> inheritedDependencyConstraints;
    private DefaultDependencySet allDependencies;
    private DefaultDependencyConstraintSet allDependencyConstraints;