delegate.clear();
    }

    @Override
    public Object[] toArray() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.toArray();
    }

    @Override
    public <T> T[] toArray(T[] array) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.toArray(array);
    }

    private static final long serialVersionUID = 0;
  }

      delegate.clear();
    }

    @Override
    public Object[] toArray() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.toArray();
    }

    @Override
    public <T> T[] toArray(T[] array) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.toArray(array);
    }

    @Override
    public void addFirst(E e) {

      return super.size();
    }

    @Override
    public Object[] toArray() {
      assertTrue(Thread.holdsLock(mutex));
      return super.toArray();
    }

    @Override
    public <T> T[] toArray(T[] a) {
      assertTrue(Thread.holdsLock(mutex));
      return super.toArray(a);
    }

    private static final long serialVersionUID = 0;
  }

  }

  @Override
  public boolean isEmpty() {
    return delegate.isEmpty();
  }

  @Override
  public Object[] toArray() {
    return delegate.toArray();
  }

  @Override
  public <T extends @Nullable Object> T[] toArray(T[] other) {
    return delegate.toArray(other);
  }

  @Override
  public String toString() {
    return delegate.toString();
  }

            Object[] array = s.toArray();
            for (int i = 0; i < 2; i++) {
                assertEquals(values[i], array[i]);
            }
        });
    }

    public void test_ofNull() {
        assertEquals(0, (int) StreamUtil.stream().get(s -> s.toArray().length));
        Object[] o = {};
        assertEquals(0, (int) StreamUtil.stream(o).get(s -> s.toArray().length));

        cache.put(project1, new SetWithResolutionResult(null, artifacts));

        assertArrayEquals(
                artifacts.toArray(new Artifact[0]),
                cache.get(project1).getArtifacts().toArray(new Artifact[0]));

        ProjectArtifactsCache.Key project2 = new ProjectArtifactsCache.Key() {};

        Set<Artifact> reversedArtifacts = new LinkedHashSet<>(4);

    }
    return standardAddAll(collection);
  }

  @Override
  @J2ktIncompatible // Incompatible return type change. Use inherited implementation
  public Object[] toArray() {
    /*
     * If we could, we'd declare the no-arg `Collection.toArray()` to return "Object[] but elements
     * have the same nullness as E." Since we can't, we declare it to return nullable elements, and

              return false;
            }
          }

          @Override
          @SuppressWarnings("nullness") // b/192354773 in our checker affects toArray declarations
          public <T extends @Nullable Object> T[] toArray(T[] array) {
            T[] result = super.toArray(array);
            if (size() < result.length) {
              // It works around a GWT bug where elements after last is not
              // properly null'ed.

      return super.size();
    }

    @Override
    public Object[] toArray() {
      assertTrue(Thread.holdsLock(mutex));
      return super.toArray();
    }

    @Override
    public <T> T[] toArray(T[] a) {
      assertTrue(Thread.holdsLock(mutex));
      return super.toArray(a);
    }

    private static final long serialVersionUID = 0;
  }

    return new SafeTreeSet<>(delegate.tailSet(checkValid(fromElement), inclusive));
  }

  @Override
  public Object[] toArray() {
    return delegate.toArray();
  }

  @Override
  public <T> T[] toArray(T[] a) {
    return delegate.toArray(a);
  }

  @CanIgnoreReturnValue
  private <T> T checkValid(T t) {
    // a ClassCastException is what's supposed to happen!