def __init__(self, db, prefix, reverse):
self.prefix = prefix
if reverse:
self.iterator = reversed(db.iteritems())
nxt_prefix = util.increment_byte_string(prefix)
if nxt_prefix:
self.iterator.seek(nxt_prefix)
try:
next(self.iterator)
except StopIteration:
self.iterator.seek(nxt_prefix)
else:
self.iterator.seek_to_last()
else:
self.iterator = db.iteritems()
self.iterator.seek(prefix)
def test_increment_byte_string():
assert util.increment_byte_string(b'1') == b'2'
assert util.increment_byte_string(b'\x01\x01') == b'\x01\x02'
assert util.increment_byte_string(b'\xff\xff') is None
