`UnmodifiableMultimap.forEach` uses the `Multimap.forEach` default implementation which involves listing entries, and creating a new lambda instead of simply passing the BiConsumer through to the protected instance. This is safe to pass directly though because `forEach(BiConsumer)` is a read-only operation.
assertThat(Comparators.max(2, 1, reverse)).isEqualTo(1);
  }
  public void testMinMaxComparator_equalInstances() {
    Comparator<Foo> natural = Ordering.natural();
    Comparator<Foo> reverse = Collections.reverseOrder(natural);
    Foo a = new Foo(1);
    Foo b = new Foo(1);
    assertThat(Comparators.min(a, b, reverse)).isSameInstanceAs(a);
    assertThat(Comparators.max(a, b, reverse)).isSameInstanceAs(a);
  }
  private static class Foo implements Comparable<Foo> {
    final Integer value;
    Foo(int value) {
      this.value = value;
    }
    @Override
    public int hashCode() {
      return value.hashCode();
    }
    @Override
    public boolean equals(Object o) {
      return (o instanceof Foo) && ((Foo) o).value.equals(value);
    }
    @Override
    public int compareTo(Foo other) {
      return value.compareTo(other.value);
    }
  }
}