* recursion by calling {@link #visit} for any {@code Type} while visitation is in progress. For
 * example, this can be used to reject wildcards or type variables contained in a type as in:
 *
 * {@snippet :
 * new TypeVisitor() {
 *   protected void visitParameterizedType(ParameterizedType t) {
 *     visit(t.getOwnerType());
 *     visit(t.getActualTypeArguments());
 *   }
 *   protected void visitGenericArrayType(GenericArrayType t) {

import java.lang.reflect.WildcardType;
import java.util.ArrayList;
import java.util.EnumSet;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests of {@link TypeVisitor}.
 *
 * @author Ben Yu
 */
@NullUnmarked
public class TypeVisitorTest extends TestCase {

  public void testVisitNull() {
    new BaseTypeVisitor()