assertSame( bin2hex($extraField), '0100' // 2 bytes; Tag for this "extra" block type . '1c00' // 2 bytes; Size of this "extra" block . '6666666677777777' // 8 bytes; Original uncompressed file size . '8888888899999999' // 8 bytes; Size of compressed data . '1111111122222222' // 8 bytes; Offset of local header record . '33333333' // 4 bytes; Number of the disk on which this file starts ); } public function testSerializesEmptyCorrectly(): void { $extraField = ExtendedInformationExtraField::generate(); $this->assertSame( bin2hex($extraField), '0100' // 2 bytes; Tag for this "extra" block type . '0000' // 2 bytes; Size of this "extra" block ); } }