return !disjoint(a, b);
  }

  private static Method extractMethod(Test test) {
    if (test instanceof AbstractTester) {
      AbstractTester<?> tester = (AbstractTester<?>) test;
      return getMethod(tester.getClass(), tester.getTestMethodName());
    } else if (test instanceof TestCase) {
      TestCase testCase = (TestCase) test;
      return getMethod(testCase.getClass(), testCase.getName());

    return !disjoint(a, b);
  }

  private static Method extractMethod(Test test) {
    if (test instanceof AbstractTester) {
      AbstractTester<?> tester = (AbstractTester<?>) test;
      return getMethod(tester.getClass(), tester.getTestMethodName());
    } else if (test instanceof TestCase) {
      TestCase testCase = (TestCase) test;
      return getMethod(testCase.getClass(), testCase.getName());

  public void testNullEqualityGroup() {
    EqualsTester tester = new EqualsTester();
    assertThrows(NullPointerException.class, () -> tester.addEqualityGroup((Object[]) null));
  }

  public void testNullObjectInEqualityGroup() {
    EqualsTester tester = new EqualsTester();
    NullPointerException e =
        assertThrows(NullPointerException.class, () -> tester.addEqualityGroup(1, null, 3));

  public void testNullEqualityGroup() {
    EqualsTester tester = new EqualsTester();
    assertThrows(NullPointerException.class, () -> tester.addEqualityGroup((Object[]) null));
  }

  public void testNullObjectInEqualityGroup() {
    EqualsTester tester = new EqualsTester();
    NullPointerException e =
        assertThrows(NullPointerException.class, () -> tester.addEqualityGroup(1, null, 3));

    List<Class<? extends AbstractTester>> testers = copyToList(super.getTesters());
    testers.add(CollectionSerializationEqualTester.class);
    testers.add(MultisetAddTester.class);
    testers.add(MultisetContainsTester.class);
    testers.add(MultisetCountTester.class);
    testers.add(MultisetElementSetTester.class);
    testers.add(MultisetEqualsTester.class);
    testers.add(MultisetForEachEntryTester.class);

import com.google.common.collect.testing.testers.MapIsEmptyTester;
import com.google.common.collect.testing.testers.MapPutAllTester;
import com.google.common.collect.testing.testers.MapPutTester;
import com.google.common.collect.testing.testers.MapRemoveTester;
import com.google.common.collect.testing.testers.MapSerializationTester;
import com.google.common.collect.testing.testers.MapSizeTester;

    List<Class<? extends AbstractTester>> testers = copyToList(super.getTesters());
    testers.add(CollectionSerializationEqualTester.class);
    testers.add(MultisetAddTester.class);
    testers.add(MultisetContainsTester.class);
    testers.add(MultisetCountTester.class);
    testers.add(MultisetElementSetTester.class);
    testers.add(MultisetEqualsTester.class);
    testers.add(MultisetReadsTester.class);

  private final ForwardingWrapperTester tester = new ForwardingWrapperTester();

  public void testGoodForwarder() {
    tester.testForwarding(
        Arithmetic.class,
        new Function<Arithmetic, Arithmetic>() {
          @Override
          public Arithmetic apply(Arithmetic arithmetic) {
            return new ForwardingArithmetic(arithmetic);
          }
        });
    tester.testForwarding(

    @Require
    @NotTesterAnnotation
    class Tester {}

    assertThat(getTesterAnnotations(Tester.class))
        .containsExactly(Tester.class.getAnnotation(Require.class));
  }

  public void testGetTesterAnnotations_method() throws Exception {
    class Tester {
      @Keep
      @Require
      @NotTesterAnnotation
      public void test() {}
    }

    @Require
    @NotTesterAnnotation
    class Tester {}

    assertThat(getTesterAnnotations(Tester.class))
        .containsExactly(Tester.class.getAnnotation(Require.class));
  }

  public void testGetTesterAnnotations_method() throws Exception {
    class Tester {
      @Keep
      @Require
      @NotTesterAnnotation
      public void test() {}
    }