[utils] Add generic caesar cipher and rot47

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Sergey M․ 2019-11-27 02:26:42 +07:00
parent 6ddd4bf6ac
commit 1ced222120
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2 changed files with 29 additions and 0 deletions

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@ -19,6 +19,7 @@ from youtube_dl.utils import (
age_restricted,
args_to_str,
encode_base_n,
caesar,
clean_html,
date_from_str,
DateRange,
@ -69,6 +70,7 @@ from youtube_dl.utils import (
remove_start,
remove_end,
remove_quotes,
rot47,
shell_quote,
smuggle_url,
str_to_int,
@ -1369,6 +1371,20 @@ Line 1
self.assertRaises(ValueError, encode_base_n, 0, 70)
self.assertRaises(ValueError, encode_base_n, 0, 60, custom_table)
def test_caesar(self):
self.assertEqual(caesar('ace', 'abcdef', 2), 'cea')
self.assertEqual(caesar('cea', 'abcdef', -2), 'ace')
self.assertEqual(caesar('ace', 'abcdef', -2), 'eac')
self.assertEqual(caesar('eac', 'abcdef', 2), 'ace')
self.assertEqual(caesar('ace', 'abcdef', 0), 'ace')
self.assertEqual(caesar('xyz', 'abcdef', 2), 'xyz')
self.assertEqual(caesar('abc', 'acegik', 2), 'ebg')
self.assertEqual(caesar('ebg', 'acegik', -2), 'abc')
def test_rot47(self):
self.assertEqual(rot47('youtube-dl'), r'J@FEF36\5=')
self.assertEqual(rot47('YOUTUBE-DL'), r'*~&%&qt\s{')
def test_urshift(self):
self.assertEqual(urshift(3, 1), 1)
self.assertEqual(urshift(-3, 1), 2147483646)

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@ -5383,6 +5383,19 @@ def decode_packed_codes(code):
obfucasted_code)
def caesar(s, alphabet, shift):
if shift == 0:
return s
l = len(alphabet)
return ''.join(
alphabet[(alphabet.index(c) + shift) % l] if c in alphabet else c
for c in s)
def rot47(s):
return caesar(s, r'''!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~''', 47)
def parse_m3u8_attributes(attrib):
info = {}
for (key, val) in re.findall(r'(?P<key>[A-Z0-9-]+)=(?P<val>"[^"]+"|[^",]+)(?:,|$)', attrib):