private static class DefaultAttributeSelectionSchema implements AttributeSelectionSchema {
        private final AttributesSchemaInternal consumerSchema;
        private final AttributesSchemaInternal producerSchema;

        private final Map<ExtraAttributesEntry, Attribute<?>[]> extraAttributesCache;

import org.gradle.util.SnapshotTestUtil
import org.gradle.util.TestUtil
import spock.lang.Specification

import static org.gradle.util.TestUtil.objectFactory
/**
 * Tests {@link DefaultAttributesSchema.DefaultAttributeSelectionSchema}. The class-under-test should
 * eventually be moved into its own file so that we don't need to instantiate it indirectly through a