'''Tests varblock operations.'''


try:
    from StringIO import StringIO as BytesIO
except ImportError:
    from io import BytesIO
import unittest

import rsa
from rsa._compat import b
from rsa import varblock

class VarintTest(unittest.TestCase):

    def test_read_varint(self):
        
        encoded = b('\xac\x02crummy')
        infile = BytesIO(encoded)

        (decoded, read) = varblock.read_varint(infile)

        # Test the returned values
        self.assertEqual(300, decoded)
        self.assertEqual(2, read)

        # The rest of the file should be untouched
        self.assertEqual(b('crummy'), infile.read())

    def test_read_zero(self):
        
        encoded = b('\x00crummy')
        infile = BytesIO(encoded)

        (decoded, read) = varblock.read_varint(infile)

        # Test the returned values
        self.assertEqual(0, decoded)
        self.assertEqual(1, read)

        # The rest of the file should be untouched
        self.assertEqual(b('crummy'), infile.read())

    def test_write_varint(self):
        
        expected = b('\xac\x02')
        outfile = BytesIO()

        written = varblock.write_varint(outfile, 300)

        # Test the returned values
        self.assertEqual(expected, outfile.getvalue())
        self.assertEqual(2, written)


    def test_write_zero(self):
        
        outfile = BytesIO()
        written = varblock.write_varint(outfile, 0)

        # Test the returned values
        self.assertEqual(b('\x00'), outfile.getvalue())
        self.assertEqual(1, written)


class VarblockTest(unittest.TestCase):

    def test_yield_varblock(self):
        infile = BytesIO(b('\x01\x0512345\x06Sybren'))

        varblocks = list(varblock.yield_varblocks(infile))
        self.assertEqual([b('12345'), b('Sybren')], varblocks)

class FixedblockTest(unittest.TestCase):

    def test_yield_fixedblock(self):

        infile = BytesIO(b('123456Sybren'))

        fixedblocks = list(varblock.yield_fixedblocks(infile, 6))
        self.assertEqual([b('123456'), b('Sybren')], fixedblocks)