public function testBitsDiffering()
{
$this->assertEquals(0, FormatInformation::numBitsDiffering(1, 1));
$this->assertEquals(1, FormatInformation::numBitsDiffering(0, 2));
$this->assertEquals(2, FormatInformation::numBitsDiffering(1, 2));
$this->assertEquals(32, FormatInformation::numBitsDiffering(-1, 0));
}
/**
* Decodes version information from an integer and returns the version.
*
* @param integer $versionBits
* @return Version|null
*/
public static function decodeVersionInformation($versionBits)
{
$bestDifference = PHP_INT_MAX;
$bestVersion = 0;
foreach (self::$versionDecodeInfo as $i => $targetVersion) {
if ($targetVersion === $versionBits) {
return self::getVersionForNumber($i + 7);
}
$bitsDifference = FormatInformation::numBitsDiffering($versionBits, $targetVersion);
if ($bitsDifference < $bestDifference) {
$bestVersion = $i + 7;
$bestDifference = $bitsDifference;
}
}
if ($bestDifference <= 3) {
return self::getVersionForNumber($bestVersion);
}
return null;
}
