Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/securesystemslib/_internal/utils.py: 39%

1"""Internal utilities""" 

2 

3import base64 

4import binascii 

5from typing import Any 

6 

7 

8def make_hashable(value: Any) -> Any: 

9 """Return a hashable equivalent of a dict or list, for use in __hash__ 

10 

11 Dicts become frozensets of their items and lists become tuples, both 

12 recursively. Values that are already hashable are returned as they are, so 

13 the result compares equal whenever the input does, which is what __hash__ 

14 needs. 

15 

16 Arguments: 

17 value: Value to convert 

18 

19 Returns: 

20 A hashable equivalent of the value 

21 """ 

22 

23 if isinstance(value, dict): 

24 return frozenset((k, make_hashable(v)) for k, v in value.items()) 

25 if isinstance(value, (list, tuple)): 

26 return tuple(make_hashable(v) for v in value) 

27 return value 

28 

29 

30def b64enc(data: bytes) -> str: 

31 """To encode byte sequence into base64 string 

32 

33 Arguments: 

34 data: Byte sequence to encode 

35 

36 Exceptions: 

37 TypeError: If "data" is not byte sequence 

38 

39 Returns: 

40 base64 string 

41 """ 

42 

43 return base64.standard_b64encode(data).decode("utf-8") 

44 

45 

46def b64dec(string: str) -> bytes: 

47 """To decode byte sequence from base64 string 

48 

49 Arguments: 

50 string: base64 string to decode 

51 

52 Raises: 

53 binascii.Error: If invalid base64-encoded string 

54 

55 Returns: 

56 A byte sequence 

57 """ 

58 

59 data = string.encode("utf-8") 

60 try: 

61 return base64.b64decode(data, validate=True) 

62 except binascii.Error: 

63 # altchars for urlsafe encoded base64 - instead of + and _ instead of / 

64 return base64.b64decode(data, altchars=b"-_", validate=True)