# Python code coverage for Lib/_weakrefset.py

# | count | content |
---|---|---|

1 | n/a | # Access WeakSet through the weakref module. |

2 | n/a | # This code is separated-out because it is needed |

3 | n/a | # by abc.py to load everything else at startup. |

4 | n/a | |

5 | n/a | from _weakref import ref |

6 | n/a | |

7 | n/a | __all__ = ['WeakSet'] |

8 | n/a | |

9 | n/a | |

10 | n/a | class _IterationGuard: |

11 | n/a | # This context manager registers itself in the current iterators of the |

12 | n/a | # weak container, such as to delay all removals until the context manager |

13 | n/a | # exits. |

14 | n/a | # This technique should be relatively thread-safe (since sets are). |

15 | n/a | |

16 | n/a | def __init__(self, weakcontainer): |

17 | n/a | # Don't create cycles |

18 | n/a | self.weakcontainer = ref(weakcontainer) |

19 | n/a | |

20 | n/a | def __enter__(self): |

21 | n/a | w = self.weakcontainer() |

22 | n/a | if w is not None: |

23 | n/a | w._iterating.add(self) |

24 | n/a | return self |

25 | n/a | |

26 | n/a | def __exit__(self, e, t, b): |

27 | n/a | w = self.weakcontainer() |

28 | n/a | if w is not None: |

29 | n/a | s = w._iterating |

30 | n/a | s.remove(self) |

31 | n/a | if not s: |

32 | n/a | w._commit_removals() |

33 | n/a | |

34 | n/a | |

35 | n/a | class WeakSet: |

36 | n/a | def __init__(self, data=None): |

37 | n/a | self.data = set() |

38 | n/a | def _remove(item, selfref=ref(self)): |

39 | n/a | self = selfref() |

40 | n/a | if self is not None: |

41 | n/a | if self._iterating: |

42 | n/a | self._pending_removals.append(item) |

43 | n/a | else: |

44 | n/a | self.data.discard(item) |

45 | n/a | self._remove = _remove |

46 | n/a | # A list of keys to be removed |

47 | n/a | self._pending_removals = [] |

48 | n/a | self._iterating = set() |

49 | n/a | if data is not None: |

50 | n/a | self.update(data) |

51 | n/a | |

52 | n/a | def _commit_removals(self): |

53 | n/a | l = self._pending_removals |

54 | n/a | discard = self.data.discard |

55 | n/a | while l: |

56 | n/a | discard(l.pop()) |

57 | n/a | |

58 | n/a | def __iter__(self): |

59 | n/a | with _IterationGuard(self): |

60 | n/a | for itemref in self.data: |

61 | n/a | item = itemref() |

62 | n/a | if item is not None: |

63 | n/a | # Caveat: the iterator will keep a strong reference to |

64 | n/a | # `item` until it is resumed or closed. |

65 | n/a | yield item |

66 | n/a | |

67 | n/a | def __len__(self): |

68 | n/a | return len(self.data) - len(self._pending_removals) |

69 | n/a | |

70 | n/a | def __contains__(self, item): |

71 | n/a | try: |

72 | n/a | wr = ref(item) |

73 | n/a | except TypeError: |

74 | n/a | return False |

75 | n/a | return wr in self.data |

76 | n/a | |

77 | n/a | def __reduce__(self): |

78 | n/a | return (self.__class__, (list(self),), |

79 | n/a | getattr(self, '__dict__', None)) |

80 | n/a | |

81 | n/a | def add(self, item): |

82 | n/a | if self._pending_removals: |

83 | n/a | self._commit_removals() |

84 | n/a | self.data.add(ref(item, self._remove)) |

85 | n/a | |

86 | n/a | def clear(self): |

87 | n/a | if self._pending_removals: |

88 | n/a | self._commit_removals() |

89 | n/a | self.data.clear() |

90 | n/a | |

91 | n/a | def copy(self): |

92 | n/a | return self.__class__(self) |

93 | n/a | |

94 | n/a | def pop(self): |

95 | n/a | if self._pending_removals: |

96 | n/a | self._commit_removals() |

97 | n/a | while True: |

98 | n/a | try: |

99 | n/a | itemref = self.data.pop() |

100 | n/a | except KeyError: |

101 | n/a | raise KeyError('pop from empty WeakSet') |

102 | n/a | item = itemref() |

103 | n/a | if item is not None: |

104 | n/a | return item |

105 | n/a | |

106 | n/a | def remove(self, item): |

107 | n/a | if self._pending_removals: |

108 | n/a | self._commit_removals() |

109 | n/a | self.data.remove(ref(item)) |

110 | n/a | |

111 | n/a | def discard(self, item): |

112 | n/a | if self._pending_removals: |

113 | n/a | self._commit_removals() |

114 | n/a | self.data.discard(ref(item)) |

115 | n/a | |

116 | n/a | def update(self, other): |

117 | n/a | if self._pending_removals: |

118 | n/a | self._commit_removals() |

119 | n/a | for element in other: |

120 | n/a | self.add(element) |

121 | n/a | |

122 | n/a | def __ior__(self, other): |

123 | n/a | self.update(other) |

124 | n/a | return self |

125 | n/a | |

126 | n/a | def difference(self, other): |

127 | n/a | newset = self.copy() |

128 | n/a | newset.difference_update(other) |

129 | n/a | return newset |

130 | n/a | __sub__ = difference |

131 | n/a | |

132 | n/a | def difference_update(self, other): |

133 | n/a | self.__isub__(other) |

134 | n/a | def __isub__(self, other): |

135 | n/a | if self._pending_removals: |

136 | n/a | self._commit_removals() |

137 | n/a | if self is other: |

138 | n/a | self.data.clear() |

139 | n/a | else: |

140 | n/a | self.data.difference_update(ref(item) for item in other) |

141 | n/a | return self |

142 | n/a | |

143 | n/a | def intersection(self, other): |

144 | n/a | return self.__class__(item for item in other if item in self) |

145 | n/a | __and__ = intersection |

146 | n/a | |

147 | n/a | def intersection_update(self, other): |

148 | n/a | self.__iand__(other) |

149 | n/a | def __iand__(self, other): |

150 | n/a | if self._pending_removals: |

151 | n/a | self._commit_removals() |

152 | n/a | self.data.intersection_update(ref(item) for item in other) |

153 | n/a | return self |

154 | n/a | |

155 | n/a | def issubset(self, other): |

156 | n/a | return self.data.issubset(ref(item) for item in other) |

157 | n/a | __le__ = issubset |

158 | n/a | |

159 | n/a | def __lt__(self, other): |

160 | n/a | return self.data < set(ref(item) for item in other) |

161 | n/a | |

162 | n/a | def issuperset(self, other): |

163 | n/a | return self.data.issuperset(ref(item) for item in other) |

164 | n/a | __ge__ = issuperset |

165 | n/a | |

166 | n/a | def __gt__(self, other): |

167 | n/a | return self.data > set(ref(item) for item in other) |

168 | n/a | |

169 | n/a | def __eq__(self, other): |

170 | n/a | if not isinstance(other, self.__class__): |

171 | n/a | return NotImplemented |

172 | n/a | return self.data == set(ref(item) for item in other) |

173 | n/a | |

174 | n/a | def symmetric_difference(self, other): |

175 | n/a | newset = self.copy() |

176 | n/a | newset.symmetric_difference_update(other) |

177 | n/a | return newset |

178 | n/a | __xor__ = symmetric_difference |

179 | n/a | |

180 | n/a | def symmetric_difference_update(self, other): |

181 | n/a | self.__ixor__(other) |

182 | n/a | def __ixor__(self, other): |

183 | n/a | if self._pending_removals: |

184 | n/a | self._commit_removals() |

185 | n/a | if self is other: |

186 | n/a | self.data.clear() |

187 | n/a | else: |

188 | n/a | self.data.symmetric_difference_update(ref(item, self._remove) for item in other) |

189 | n/a | return self |

190 | n/a | |

191 | n/a | def union(self, other): |

192 | n/a | return self.__class__(e for s in (self, other) for e in s) |

193 | n/a | __or__ = union |

194 | n/a | |

195 | n/a | def isdisjoint(self, other): |

196 | n/a | return len(self.intersection(other)) == 0 |