if (upper == POSITIVE_INFINITY) {
        // Return NaN when lower == NEGATIVE_INFINITY and upper == POSITIVE_INFINITY:
        return NaN;
      }
      // Return NEGATIVE_INFINITY when NEGATIVE_INFINITY == lower <= upper < POSITIVE_INFINITY:
      return NEGATIVE_INFINITY;
    }
    if (upper == POSITIVE_INFINITY) {

   * contains both {@link Double#POSITIVE_INFINITY} and {@link Double#NEGATIVE_INFINITY} then the
   * result is {@link Double#NaN}. If it contains {@link Double#POSITIVE_INFINITY} and finite values
   * only or {@link Double#POSITIVE_INFINITY} only, the result is {@link Double#POSITIVE_INFINITY}.
   * If it contains {@link Double#NEGATIVE_INFINITY} and finite values only or {@link

   * contains both {@link Double#POSITIVE_INFINITY} and {@link Double#NEGATIVE_INFINITY} then the
   * result is {@link Double#NaN}. If it contains {@link Double#POSITIVE_INFINITY} and finite values
   * only or {@link Double#POSITIVE_INFINITY} only, the result is {@link Double#POSITIVE_INFINITY}.
   * If it contains {@link Double#NEGATIVE_INFINITY} and finite values only or {@link

  public void testRoundInfiniteToIntAlwaysFails() {
    for (RoundingMode mode : ALL_ROUNDING_MODES) {
      assertThrows(
          ArithmeticException.class, () -> DoubleMath.roundToInt(Double.POSITIVE_INFINITY, mode));
      assertThrows(
          ArithmeticException.class, () -> DoubleMath.roundToInt(Double.NEGATIVE_INFINITY, mode));
    }
  }

  @GwtIncompatible // DoubleMath.roundToLong(double, RoundingMode)

    assertThrows(IllegalStateException.class, () -> EMPTY_PAIRED_STATS.populationCovariance());
    assertThat(ONE_VALUE_PAIRED_STATS.populationCovariance()).isEqualTo(0.0);
    assertThat(createSingleStats(Double.POSITIVE_INFINITY, 1.23).populationCovariance()).isNaN();
    assertThat(createSingleStats(Double.NEGATIVE_INFINITY, 1.23).populationCovariance()).isNaN();
    assertThat(createSingleStats(Double.NaN, 1.23).populationCovariance()).isNaN();

    assertThrows(IllegalStateException.class, () -> EMPTY_PAIRED_STATS.populationCovariance());
    assertThat(ONE_VALUE_PAIRED_STATS.populationCovariance()).isEqualTo(0.0);
    assertThat(createSingleStats(Double.POSITIVE_INFINITY, 1.23).populationCovariance()).isNaN();
    assertThat(createSingleStats(Double.NEGATIVE_INFINITY, 1.23).populationCovariance()).isNaN();
    assertThat(createSingleStats(Double.NaN, 1.23).populationCovariance()).isNaN();

    ImmutableDoubleArray iia =
        ImmutableDoubleArray.of(-0.0, 0.0, Double.MAX_VALUE, Double.POSITIVE_INFINITY, Double.NaN);
    assertThat(iia.indexOf(-0.0)).isEqualTo(0);
    assertThat(iia.indexOf(0.0)).isEqualTo(1);
    assertThat(iia.indexOf(Double.MAX_VALUE)).isEqualTo(2);
    assertThat(iia.indexOf(Double.POSITIVE_INFINITY)).isEqualTo(3);
    assertThat(iia.indexOf(Double.NaN)).isEqualTo(4);
  }

   * representable as a double, but {@code roundToDouble(BigDecimal.valueOf(2).pow(2000), HALF_UP)}
   * will return {@code Double.MAX_VALUE}, not {@code Double.POSITIVE_INFINITY}.
   *
   * <p>For the case of {@link RoundingMode#HALF_EVEN}, this implementation uses the IEEE 754
   * default rounding mode: if the two nearest representable values are equally near, the one with

        format.formatRate(builder, Double.NaN);
        assertEquals("? B/s", builder.build());

        // Test Infinity
        builder = new DefaultMessageBuilder();
        format.formatRate(builder, Double.POSITIVE_INFINITY);
        assertEquals("? B/s", builder.build());

        builder = new DefaultMessageBuilder();
        format.formatRate(builder, Double.NEGATIVE_INFINITY);
        assertEquals("? B/s", builder.build());

  }

  static final ImmutableSet<Double> INTEGRAL_DOUBLE_CANDIDATES;
  static final ImmutableSet<Double> FRACTIONAL_DOUBLE_CANDIDATES;
  static final Iterable<Double> INFINITIES =
      Doubles.asList(Double.POSITIVE_INFINITY, Double.NEGATIVE_INFINITY);
  static final Iterable<Double> FINITE_DOUBLE_CANDIDATES;
  static final Iterable<Double> POSITIVE_FINITE_DOUBLE_CANDIDATES;
  static final Iterable<Double> ALL_DOUBLE_CANDIDATES;