doTestEmpty(noneOf("CharMatcher"));
    doTestEmpty(inRange('n', 'q'));
    doTestEmpty(forPredicate(Predicates.equalTo('c')));
  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNull() throws Exception {
    doTestNull(CharMatcher.any());
    doTestNull(CharMatcher.none());
    doTestNull(is('a'));
    doTestNull(isNot('a'));
    doTestNull(anyOf(""));
    doTestNull(anyOf("x"));

    doTestEmpty(noneOf("CharMatcher"));
    doTestEmpty(inRange('n', 'q'));
    doTestEmpty(forPredicate(Predicates.equalTo('c')));
  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNull() throws Exception {
    doTestNull(CharMatcher.any());
    doTestNull(CharMatcher.none());
    doTestNull(is('a'));
    doTestNull(isNot('a'));
    doTestNull(anyOf(""));
    doTestNull(anyOf("x"));

    }

    /**
     * Test rule order preservation
     */
    public void test_ruleOrderPreservation() {
        TestRule rule1 = new TestRule("rule1", false);
        TestRule rule2 = new TestRule("rule2", true);
        TestRule rule3 = new TestRule("rule3", false);
        TestRule rule4 = new TestRule("rule4", true);

        ruleManager.addRule(rule1);
        ruleManager.addRule(rule2);
        ruleManager.addRule(rule3);

        TestResponseProcessor sharedProcessor = new TestResponseProcessor("shared");

        TestRule rule1 = new TestRule("rule1", sharedProcessor, true);
        TestRule rule2 = new TestRule("rule2", sharedProcessor, false);
        TestRule rule3 = new TestRule("rule3", sharedProcessor, true);

        // Same processor instance
        assertSame(sharedProcessor, rule1.getResponseProcessor());

        // Initial state
        assertNull(testRule.getRuleId());

        // Set rule ID
        testRule.setRuleId("testRule1");
        assertEquals("testRule1", testRule.getRuleId());

        // Change rule ID
        testRule.setRuleId("changedRule");
        assertEquals("changedRule", testRule.getRuleId());

        // Set null rule ID
        testRule.setRuleId(null);

  }

  public void testNulls_enum() throws Exception {
    tester.testNulls(OneConstantEnum.class);
    tester.testNulls(NoConstantEnum.class);
    tester.testNulls(TimeUnit.class);
  }

  public void testNulls_parameterOptionalNotInstantiable() throws Exception {
    tester.testNulls(ConstructorParameterWithOptionalNotInstantiable.class);
  }

 * Tests for {@link RelationshipTester}.
 *
 * @author Ben Yu
 */
@NullUnmarked
public class RelationshipTesterTest extends TestCase {
  public void testNulls() {
    new ClassSanityTester()
        .setDefault(ItemReporter.class, /* itemReporter */ Item::toString)
        .testNulls(RelationshipTester.class);
  }

  }

  // ToStringHelper's tests are in ToStringHelperTest

  @J2ktIncompatible
  @GwtIncompatible("NullPointerTester")
  public void testNulls() throws Exception {
    NullPointerTester tester = new NullPointerTester();
    tester.ignore(MoreObjects.class.getMethod("firstNonNull", Object.class, Object.class));
    tester.testAllPublicStaticMethods(MoreObjects.class);

 *
 * <p>And all the created {@code Book} instances can be tested with:
 *
 * <pre>
 * new ClassSanityTester()
 *     .forAllPublicStaticMethods(Books.class)
 *     .thatReturn(Book.class)
 *     .testEquals(); // or testNulls(), testSerializable() etc.
 * </pre>
 *
 * @author Ben Yu
 * @since 14.0
 */
@GwtIncompatible
@J2ktIncompatible
@NullUnmarked
@SuppressWarnings("nullness")
public final class ClassSanityTester {

    assertCrc(0x8a9136aa, zeros);
  }

  public void testZeros100() {
    // Test 100 byte array of 0x00.
    byte[] zeros = new byte[100];
    assertCrc(0x07cb9ff6, zeros);
  }

  public void testFull() {
    // Test 32 byte array of 0xFF.
    byte[] fulls = new byte[32];
    Arrays.fill(fulls, (byte) 0xFF);
    assertCrc(0x62a8ab43, fulls);
  }

  public void testFull100() {