assertTrue(BigIntegerMath.isPowerOfTwo(result));
      assertThat(result).isAtLeast(x);
      assertThat(result).isLessThan(x.add(x));
    }
  }

  public void testFloorPowerOfTwo() {
    for (BigInteger x : POSITIVE_BIGINTEGER_CANDIDATES) {
      BigInteger result = BigIntegerMath.floorPowerOfTwo(x);
      assertTrue(BigIntegerMath.isPowerOfTwo(result));
      assertThat(result).isAtMost(x);

        assertEquals(expectedResult.intValue(), IntMath.ceilingPowerOfTwo(x));
      } else {
        assertThrows(ArithmeticException.class, () -> IntMath.ceilingPowerOfTwo(x));
      }
    }
  }

  public void testFloorPowerOfTwo() {
    for (int x : POSITIVE_INTEGER_CANDIDATES) {
      BigInteger expectedResult = BigIntegerMath.floorPowerOfTwo(BigInteger.valueOf(x));
      assertEquals(expectedResult.intValue(), IntMath.floorPowerOfTwo(x));
    }