@Managed
    static abstract class ManagedThing {
    }

    def "rule class must extend RuleSource"() {
        when:
        extract(type)

        then:
        def e = thrown(InvalidModelRuleDeclarationException)
        e.message == """Type ${fullyQualifiedNameOf(type)} is not a valid rule source:
- Rule source classes must directly extend org.gradle.model.RuleSource"""

        where:

    }

    /**
     * Creates a new rule source instance to be applied to a model element.
     *
     * @throws InvalidModelRuleDeclarationException On badly formed rule source class.
     */
    public <T> ExtractedRuleSource<T> extract(Class<T> source) throws InvalidModelRuleDeclarationException {
        try {
            return cache.get(source).newInstance(source);
        } catch (ExecutionException e) {

import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import com.google.common.collect.Multimap;
import org.gradle.model.ConfigurationCycleException;
import org.gradle.model.InvalidModelRuleDeclarationException;
import org.gradle.model.RuleSource;
import org.gradle.model.internal.core.EmptyModelProjection;
import org.gradle.model.internal.core.ModelAction;
import org.gradle.model.internal.core.ModelActionRole;