tests.py

from unittest import TestCase
from formats import xor
from opgp_modification import OpenPgpMsg


class TestModifier(TestCase):

    def test_xor_bytes(self):
        """
        Checks if the result is correct.
        Manually calculation:

        aG = 97 71  = 0110 0001 0100 0111
        9s = 57 115 = 0011 1001 0111 0011
        ---------------------------------
        X4 = 88 52  = 0101 1000 0011 0100
        """
        testbytes_1 = b'aG'
        testbytes_2 = b'9s'

        expected_res = b'X4'
        actual_res = xor(testbytes_1, testbytes_2)
        self.assertEqual(actual_res, expected_res)

        """
        F01    = 70  48  49 = 01000110 00110000 00110001
        Con    = 67 111 110 = 01000011 01101111 01101110
        ----------------------------------------------
        \x05__ =  5  95  95 =  00000101 01011111 01011111
        Note: Number 5 as decimal is a control character in ASCII, hence escape is needed
        """
        testbytes_3 = b'F01'
        testbytes_4 = b'Con'

        expected_res = b'\x05__'
        actual_res = xor(testbytes_3, testbytes_4)
        self.assertEqual(actual_res, expected_res)

    def test_len_encoding(self):

        first = 0xc5.to_bytes(1, byteorder="big")
        second = 0xfb.to_bytes(1, byteorder="big")
        expected_res = first + second
        self.assertEqual(OpenPgpMsg.encode_len(1723), expected_res)