}

    @Override
    Set<E> delegate() {
      return (Set<E>) super.delegate();
    }

    @Override
    public boolean equals(@Nullable Object o) {
      if (o == this) {
        return true;
      }
      synchronized (mutex) {
        return delegate().equals(o);
      }
    }

    @Override
    public int hashCode() {
      synchronized (mutex) {
        return delegate().hashCode();

    // instead of Object[].
    return delegateList().toArray(new Object[size()]);
  }

  @Override
  public boolean equals(@Nullable Object obj) {
    return delegateList().equals(obj);
  }

  @Override
  public int hashCode() {
    return delegateList().hashCode();
  }

  @Override
  public UnmodifiableIterator<E> iterator() {

            throws ArtifactResolutionException, ArtifactNotFoundException {
        if (Artifact.LATEST_VERSION.equals(artifact.getVersion())) {
            try {
                String version = resolveVersion(artifact, request);
                if (Artifact.LATEST_VERSION.equals(version)) {
                    throw new ArtifactNotFoundException("Unable to determine the latest version", artifact);
                }

        ASTNode receiver = call.getReceiver();
        if (receiver instanceof PropertyExpression) {
            if (((PropertyExpression) receiver).getPropertyAsString().equals("output")) {
                Expression objectExpr = ((PropertyExpression) receiver).getObjectExpression();
                checkIndirectOutputContains(objectExpr, call);
            }
        }
    }

  }

  @Override
  public final boolean equals(@Nullable Object obj) {
    if (obj == this) {
      return true;
    }
    if (!(obj instanceof Network)) {
      return false;
    }
    Network<?, ?> other = (Network<?, ?>) obj;

    return isDirected() == other.isDirected()
        && nodes().equals(other.nodes())
        && edgeIncidentNodesMap(this).equals(edgeIncidentNodesMap(other));
  }

    }
  }

  static class SlowElement extends Element {
    SlowElement(int hash) {
      super(hash);
    }

    @Override
    public boolean equals(@Nullable Object obj) {
      return slowItDown() != 1 && super.equals(obj);
    }

    @Override
    public int hashCode() {
      return slowItDown() + hash;
    }

    @Override
    public int compareTo(Element e) {

          }
        }
      }
      return this;
    }

    /**
     * Tests {@link Object#equals} and {@link Object#hashCode} against the return values of the
     * static methods, by asserting that when equal parameters are passed to the same static method,
     * the return value should also be equal; and vice versa.
     *
     * <p>Test fails if default value cannot be determined for a constructor or factory method

            "the Function passed to Optional.transform() must not return null."));
  }

  @Override
  public boolean equals(@Nullable Object obj) {
    if (obj instanceof Present) {
      Present<?> other = (Present<?>) obj;
      return reference.equals(other.reference);
    }
    return false;
  }

  @Override
  public int hashCode() {
    return 0x598df91c + reference.hashCode();
  }

  }

  @ListFeature.Require(SUPPORTS_SET)
  public void testReplaceAll_changesSome() {
    getList().replaceAll(e -> e.equals(samples.e0()) ? samples.e3() : e);
    E[] expected = createSamplesArray();
    for (int i = 0; i < expected.length; i++) {
      if (expected[i].equals(samples.e0())) {
        expected[i] = samples.e3();
      }
    }
    expectContents(expected);
  }

  }

  @Override
  public abstract boolean encloses(Range<C> otherRange);

  @Override
  public boolean equals(@Nullable Object obj) {
    if (obj == this) {
      return true;
    } else if (obj instanceof RangeSet) {
      RangeSet<?> other = (RangeSet<?>) obj;
      return this.asRanges().equals(other.asRanges());
    }
    return false;
  }

  @Override
  public final int hashCode() {