new EqualsTester()
          .addEqualityGroup(powerSet1, powerSet2, toHashSets(powerSet1))
          .addEqualityGroup(ImmutableSet.of())
          .addEqualityGroup(ImmutableSet.of(9999999))
          .addEqualityGroup("notASet")
          .testEquals();
      assertEquals(toHashSets(powerSet1).hashCode(), powerSet1.hashCode());
    }
  }

  public void testPowerSetEquals_independentOfOrder() {

            } else if (token.isEmpty()) {
                ranges.add(new RangeValue("", false));
            }
        }
        if (ranges.size() < 2) {
            ranges.add(new RangeValue("99999999", false));
        }
        return ranges;
    }

    private static class RangeValue {
        private String value;

        private boolean closed;

        VersionRange range = parseValid("[1.2.*]");
        assertContains(range, "1.2-alpha-1");
        assertContains(range, "1.2-SNAPSHOT");
        assertContains(range, "1.2");
        assertContains(range, "1.2.9999999");
        assertNotContains(range, "1.3-rc-1");
        assertEquals(range, parseValid(range.toString()));
    }

    @Test
    void testMissingOpenCloseDelimiter() {
        parseInvalid("1.0");
    }

        assertOrder(X_LT_Y, "1.min", "1.0");
        assertOrder(X_LT_Y, "1.min", "1.9999999999");

        assertOrder(X_EQ_Y, "1.min", "1.MIN");

        assertOrder(X_GT_Y, "1.min", "0.99999");
        assertOrder(X_GT_Y, "1.min", "0.max");
    }

    @Test
    void testMaximumSegment() {
        assertOrder(X_GT_Y, "1.max", "1.0-alpha-1");
        assertOrder(X_GT_Y, "1.max", "1.0-SNAPSHOT");