Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/dateutil/tz/_factories.py: 98%

1import _thread 

2import weakref 

3from collections import OrderedDict 

4from datetime import timedelta 

5 

6 

7class _TzSingleton(type): 

8 def __init__(cls, *args, **kwargs): 

9 cls.__instance = None 

10 super().__init__(*args, **kwargs) 

11 

12 def __call__(cls): 

13 if cls.__instance is None: 

14 cls.__instance = super().__call__() 

15 return cls.__instance 

16 

17 

18class _TzFactory(type): 

19 def instance(cls, *args, **kwargs): 

20 """Alternate constructor that returns a fresh instance""" 

21 return type.__call__(cls, *args, **kwargs) 

22 

23 

24class _TzOffsetFactory(_TzFactory): 

25 def __init__(cls, *args, **kwargs): 

26 cls.__instances = weakref.WeakValueDictionary() 

27 cls.__strong_cache = OrderedDict() 

28 cls.__strong_cache_size = 8 

29 

30 cls._cache_lock = _thread.allocate_lock() 

31 

32 def __call__(cls, name, offset): 

33 if isinstance(offset, timedelta): 

34 key = (name, offset.total_seconds()) 

35 else: 

36 key = (name, offset) 

37 

38 instance = cls.__instances.get(key, None) 

39 if instance is None: 

40 instance = cls.__instances.setdefault(key, 

41 cls.instance(name, offset)) 

42 

43 # This lock may not be necessary in Python 3. See GH issue #901 

44 with cls._cache_lock: 

45 cls.__strong_cache[key] = cls.__strong_cache.pop(key, instance) 

46 

47 # Remove an item if the strong cache is overpopulated 

48 if len(cls.__strong_cache) > cls.__strong_cache_size: 

49 cls.__strong_cache.popitem(last=False) 

50 

51 return instance 

52 

53 

54class _TzStrFactory(_TzFactory): 

55 def __init__(cls, *args, **kwargs): 

56 cls.__instances = weakref.WeakValueDictionary() 

57 cls.__strong_cache = OrderedDict() 

58 cls.__strong_cache_size = 8 

59 

60 cls.__cache_lock = _thread.allocate_lock() 

61 

62 def __call__(cls, s, posix_offset=False): 

63 key = (s, posix_offset) 

64 instance = cls.__instances.get(key, None) 

65 

66 if instance is None: 

67 instance = cls.__instances.setdefault(key, 

68 cls.instance(s, posix_offset)) 

69 

70 # This lock may not be necessary in Python 3. See GH issue #901 

71 with cls.__cache_lock: 

72 cls.__strong_cache[key] = cls.__strong_cache.pop(key, instance) 

73 

74 # Remove an item if the strong cache is overpopulated 

75 if len(cls.__strong_cache) > cls.__strong_cache_size: 

76 cls.__strong_cache.popitem(last=False) 

77 

78 return instance