def test_iterators(self):
pairs = [('c', 1), ('b', 2), ('a', 3), ('d', 4), ('e', 5), ('f', 6)]
shuffle(pairs)
od = OrderedDict(pairs)
self.assertEqual(list(od), [t[0] for t in pairs])
self.assertEqual(od.keys()[:], [t[0] for t in pairs])
self.assertEqual(od.values()[:], [t[1] for t in pairs])
self.assertEqual(od.items()[:], pairs)
self.assertEqual(list(od.iterkeys()), [t[0] for t in pairs])
self.assertEqual(list(od.itervalues()), [t[1] for t in pairs])
self.assertEqual(list(od.iteritems()), pairs)
self.assertEqual(list(reversed(od)), [t[0] for t in reversed(pairs)])
def test_iterators(self):
pairs = [('c', 1), ('b', 2), ('a', 3), ('d', 4), ('e', 5), ('f', 6)]
shuffle(pairs)
od = OrderedDict(pairs)
self.assertEqual(list(od), [t[0] for t in pairs])
self.assertEqual(od.keys()[:], [t[0] for t in pairs])
self.assertEqual(od.values()[:], [t[1] for t in pairs])
self.assertEqual(od.items()[:], pairs)
self.assertEqual(list(od.iterkeys()), [t[0] for t in pairs])
self.assertEqual(list(od.itervalues()), [t[1] for t in pairs])
self.assertEqual(list(od.iteritems()), pairs)
self.assertEqual(list(reversed(od)),
[t[0] for t in reversed(pairs)])
class OrderedSet(collections.MutableSet, collections.Sequence):
"""
An OrderedSet is a custom MutableSet that remembers its order, so that
every entry has an index that can be looked up.
Based on version written by Luminoso Technologies:
https://github.com/LuminosoInsight/ordered-set
Unlike that implementation, this class uses OrderedDict as storage
and supports key removal. We drop support for indexing, and add support
for fixed-size sets with maxlen parameter.
With a small modification, this class can be made into an LRU cache.
"""
def __init__(self, iterable=None, maxlen=None):
self._mapping = OrderedDict()
self._maxlen = maxlen
if iterable is not None:
self |= iterable
def __len__(self):
return len(self._mapping)
def __getitem__(self, index):
"""
Get the item at a given index.
If `index` is a slice, you will get back that slice of items. If it's
the slice [:], exactly the same object is returned. (If you want an
independent copy of an OrderedSet, use `OrderedSet.copy()`.)
If `index` is an iterable, you'll get the OrderedSet of items
corresponding to those indices. This is similar to NumPy's
"fancy indexing".
"""
if index == SLICE_ALL:
return self
elif hasattr(index, '__index__') or isinstance(index, slice):
result = self._mapping.keys()[index]
if isinstance(result, list):
return OrderedSet(result)
else:
return result
elif isiterable(index):
keys = self._mapping.keys()
return OrderedSet([keys[i] for i in index])
else:
raise TypeError("Don't know how to index an OrderedSet by %r" % index)
def copy(self):
return OrderedSet(self)
def __getstate__(self):
if len(self) == 0:
# The state can't be an empty list.
# We need to return a truthy value, or else __setstate__ won't be run.
#
# This could have been done more gracefully by always putting the state
# in a tuple, but this way is backwards- and forwards- compatible with
# previous versions of OrderedSet.
return (None,)
else:
return list(self)
def __setstate__(self, state):
if state == (None,):
self.__init__([])
else:
self.__init__(state)
def __contains__(self, key):
return key in self._mapping
def add(self, key):
"""
Add `key` as an item to this OrderedSet, then return its index.
If `key` is already in the OrderedSet, return the index it already
had.
"""
if key not in self._mapping:
if self._maxlen is None or len(self._mapping) < self._maxlen:
self._mapping[key] = 1
else:
self._mapping.popitem(last=False)
self._mapping[key] = 1
append = add
def discard(self, key):
del self._mapping[key]
def __iter__(self):
return self._mapping.iterkeys()
def __reversed__(self):
return reversed(self._mapping.keys())
def __repr__(self):
if not self:
return '%s()' % (self.__class__.__name__,)
return '%s(%r)' % (self.__class__.__name__, list(self))
def __eq__(self, other):
if isinstance(other, OrderedSet):
return len(self) == len(other) and \
self._mapping.keys() == other._mapping.keys()
try:
other_as_set = set(other)
except TypeError:
# If `other` can't be converted into a set, it's not equal.
return False
else:
return set(self) == other_as_set
class OrderedSet(collections.MutableSet, collections.Sequence):
"""
An OrderedSet is a custom MutableSet that remembers its order, so that
every entry has an index that can be looked up.
Based on version written by Luminoso Technologies:
https://github.com/LuminosoInsight/ordered-set
Unlike that implementation, this class uses OrderedDict as storage
and supports key removal. We drop support for indexing, and add support
for fixed-size sets with maxlen parameter.
With a small modification, this class can be made into an LRU cache.
"""
def __init__(self, iterable=None, maxlen=None):
self._mapping = OrderedDict()
self._maxlen = maxlen
if iterable is not None:
self |= iterable
def __len__(self):
return len(self._mapping)
def __getitem__(self, index):
"""
Get the item at a given index.
If `index` is a slice, you will get back that slice of items. If it's
the slice [:], exactly the same object is returned. (If you want an
independent copy of an OrderedSet, use `OrderedSet.copy()`.)
If `index` is an iterable, you'll get the OrderedSet of items
corresponding to those indices. This is similar to NumPy's
"fancy indexing".
"""
if index == SLICE_ALL:
return self
elif hasattr(index, '__index__') or isinstance(index, slice):
result = self._mapping.keys()[index]
if isinstance(result, list):
return OrderedSet(result)
else:
return result
elif isiterable(index):
keys = self._mapping.keys()
return OrderedSet([keys[i] for i in index])
else:
raise TypeError("Don't know how to index an OrderedSet by %r" %
index)
def copy(self):
return OrderedSet(self)
def __getstate__(self):
if len(self) == 0:
# The state can't be an empty list.
# We need to return a truthy value, or else __setstate__ won't be run.
#
# This could have been done more gracefully by always putting the state
# in a tuple, but this way is backwards- and forwards- compatible with
# previous versions of OrderedSet.
return (None, )
else:
return list(self)
def __setstate__(self, state):
if state == (None, ):
self.__init__([])
else:
self.__init__(state)
def __contains__(self, key):
return key in self._mapping
def add(self, key):
"""
Add `key` as an item to this OrderedSet, then return its index.
If `key` is already in the OrderedSet, return the index it already
had.
"""
if key not in self._mapping:
if self._maxlen is None or len(self._mapping) < self._maxlen:
self._mapping[key] = 1
else:
self._mapping.popitem(last=False)
self._mapping[key] = 1
append = add
def discard(self, key):
del self._mapping[key]
def __iter__(self):
return self._mapping.iterkeys()
def __reversed__(self):
return reversed(self._mapping.keys())
def __repr__(self):
if not self:
return '%s()' % (self.__class__.__name__, )
return '%s(%r)' % (self.__class__.__name__, list(self))
def __eq__(self, other):
if isinstance(other, OrderedSet):
return len(self) == len(other) and \
self._mapping.keys() == other._mapping.keys()
try:
other_as_set = set(other)
except TypeError:
# If `other` can't be converted into a set, it's not equal.
return False
else:
return set(self) == other_as_set
