Coverage for sources/frigid/__/dictionaries.py: 100%

1# vim: set filetype=python fileencoding=utf-8: 

2# -*- coding: utf-8 -*- 

3 

4#============================================================================# 

5# # 

6# Licensed under the Apache License, Version 2.0 (the "License"); # 

7# you may not use this file except in compliance with the License. # 

8# You may obtain a copy of the License at # 

9# # 

10# http://www.apache.org/licenses/LICENSE-2.0 # 

11# # 

12# Unless required by applicable law or agreed to in writing, software # 

13# distributed under the License is distributed on an "AS IS" BASIS, # 

14# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # 

15# See the License for the specific language governing permissions and # 

16# limitations under the License. # 

17# # 

18#============================================================================# 

19 

20 

21''' Internal dictionary. ''' 

22 

23# pylint: disable=unused-import 

24# ruff: noqa: F401 

25 

26 

27from __future__ import annotations 

28 

29from . import imports as __ 

30from . import immutables as _immutables 

31 

32 

33_H = __.typx.TypeVar( '_H' ) 

34_V = __.typx.TypeVar( '_V' ) 

35 

36 

37class ImmutableDictionary( 

38 _immutables.ConcealerExtension, 

39 dict[ _H, _V ], 

40 __.typx.Generic[ _H, _V ], 

41): 

42 ''' Immutable subclass of :py:class:`dict`. 

43 

44 Can be used as an instance dictionary. 

45 

46 Prevents attempts to mutate dictionary via inherited interface. 

47 ''' 

48 

49 def __init__( 

50 self, 

51 *iterables: __.DictionaryPositionalArgument[ _H, _V ], 

52 **entries: __.DictionaryNominativeArgument[ _V ], 

53 ): 

54 self._behaviors_: set[ str ] = set( ) 

55 super( ).__init__( ) 

56 from itertools import chain 

57 # Add values in order received, enforcing no alteration. 

58 for indicator, value in chain.from_iterable( map( # type: ignore 

59 lambda element: ( # type: ignore 

60 element.items( ) 

61 if isinstance( element, __.cabc.Mapping ) 

62 else element 

63 ), 

64 ( *iterables, entries ) 

65 ) ): self[ indicator ] = value # type: ignore 

66 self._behaviors_.add( _immutables.behavior_label ) 

67 

68 def __delitem__( self, key: _H ) -> None: 

69 from ..exceptions import EntryImmutabilityError 

70 raise EntryImmutabilityError( key ) 

71 

72 def __setitem__( self, key: _H, value: _V ) -> None: 

73 from ..exceptions import EntryImmutabilityError 

74 default: set[ str ] = set( ) 

75 if _immutables.behavior_label in getattr( 

76 self, '_behaviors_', default 

77 ): raise EntryImmutabilityError( key ) 

78 if key in self: raise EntryImmutabilityError( key ) 

79 super( ).__setitem__( key, value ) 

80 

81 def clear( self ) -> __.typx.Never: 

82 ''' Raises exception. Cannot clear immutable entries. ''' 

83 from ..exceptions import OperationInvalidity 

84 raise OperationInvalidity( 'clear' ) 

85 

86 def copy( self ) -> __.typx.Self: 

87 ''' Provides fresh copy of dictionary. ''' 

88 return type( self )( self ) 

89 

90 def pop( # pylint: disable=unused-argument 

91 self, key: _H, default: __.Absential[ _V ] = __.absent 

92 ) -> __.typx.Never: 

93 ''' Raises exception. Cannot pop immutable entry. ''' 

94 from ..exceptions import OperationInvalidity 

95 raise OperationInvalidity( 'pop' ) 

96 

97 def popitem( self ) -> __.typx.Never: 

98 ''' Raises exception. Cannot pop immutable entry. ''' 

99 from ..exceptions import OperationInvalidity 

100 raise OperationInvalidity( 'popitem' ) 

101 

102 def update( # type: ignore 

103 self, # pylint: disable=unused-argument 

104 *iterables: __.DictionaryPositionalArgument[ _H, _V ], 

105 **entries: __.DictionaryNominativeArgument[ _V ], 

106 ) -> None: 

107 ''' Raises exception. Cannot perform mass update. ''' 

108 from ..exceptions import OperationInvalidity 

109 raise OperationInvalidity( 'update' )