diff options
Diffstat (limited to 'lib/sqlalchemy/util.py')
| -rw-r--r-- | lib/sqlalchemy/util.py | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/lib/sqlalchemy/util.py b/lib/sqlalchemy/util.py index a4ccaac6a..9ad7e113c 100644 --- a/lib/sqlalchemy/util.py +++ b/lib/sqlalchemy/util.py @@ -620,6 +620,7 @@ class IdentitySet(object): def union(self, iterable): result = type(self)() + # testlib.pragma exempt:__hash__ result._members.update( Set(self._members.iteritems()).union(_iter_id(iterable))) return result @@ -641,6 +642,7 @@ class IdentitySet(object): def difference(self, iterable): result = type(self)() + # testlib.pragma exempt:__hash__ result._members.update( Set(self._members.iteritems()).difference(_iter_id(iterable))) return result @@ -662,6 +664,7 @@ class IdentitySet(object): def intersection(self, iterable): result = type(self)() + # testlib.pragma exempt:__hash__ result._members.update( Set(self._members.iteritems()).intersection(_iter_id(iterable))) return result @@ -683,6 +686,7 @@ class IdentitySet(object): def symmetric_difference(self, iterable): result = type(self)() + # testlib.pragma exempt:__hash__ result._members.update( Set(self._members.iteritems()).symmetric_difference(_iter_id(iterable))) return result @@ -725,13 +729,25 @@ def _iter_id(iterable): yield id(item), item +class OrderedIdentitySet(IdentitySet): + def __init__(self, iterable=None): + IdentitySet.__init__(self) + self._members = OrderedDict() + if iterable: + for o in iterable: + self.add(o) + + class UniqueAppender(object): - """appends items to a collection such that only unique items - are added.""" + """Only adds items to a collection once. + + Additional appends() of the same object are ignored. Membership is + determined by identity (``is a``) not equality (``==``). + """ def __init__(self, data, via=None): self.data = data - self._unique = Set() + self._unique = IdentitySet() if via: self._data_appender = getattr(data, via) elif hasattr(data, 'append'): |