--- /dev/null
+"""
+An OrderedSet is a custom MutableSet that remembers its order, so that every
+entry has an index that can be looked up.
+
+Based on a recipe originally posted to ActiveState Recipes by Raymond Hettiger,
+and released under the MIT license.
+"""
+import itertools as it
+from collections import deque
+
+try:
+ # Python 3
+ from collections.abc import MutableSet, Sequence
+except ImportError:
+ # Python 2.7
+ from collections import MutableSet, Sequence
+
+SLICE_ALL = slice(None)
+__version__ = "3.1"
+
+
+def is_iterable(obj):
+ """
+ Are we being asked to look up a list of things, instead of a single thing?
+ We check for the `__iter__` attribute so that this can cover types that
+ don't have to be known by this module, such as NumPy arrays.
+
+ Strings, however, should be considered as atomic values to look up, not
+ iterables. The same goes for tuples, since they are immutable and therefore
+ valid entries.
+
+ We don't need to check for the Python 2 `unicode` type, because it doesn't
+ have an `__iter__` attribute anyway.
+ """
+ return (
+ hasattr(obj, "__iter__")
+ and not isinstance(obj, str)
+ and not isinstance(obj, tuple)
+ )
+
+
+class OrderedSet(MutableSet, Sequence):
+ """
+ An OrderedSet is a custom MutableSet that remembers its order, so that
+ every entry has an index that can be looked up.
+
+ Example:
+ >>> OrderedSet([1, 1, 2, 3, 2])
+ OrderedSet([1, 2, 3])
+ """
+
+ def __init__(self, iterable=None):
+ self.items = []
+ self.map = {}
+ if iterable is not None:
+ self |= iterable
+
+ def __len__(self):
+ """
+ Returns the number of unique elements in the ordered set
+
+ Example:
+ >>> len(OrderedSet([]))
+ 0
+ >>> len(OrderedSet([1, 2]))
+ 2
+ """
+ return len(self.items)
+
+ def __getitem__(self, index):
+ """
+ Get the item at a given index.
+
+ If `index` is a slice, you will get back that slice of items, as a
+ new OrderedSet.
+
+ If `index` is a list or a similar iterable, you'll get a list of
+ items corresponding to those indices. This is similar to NumPy's
+ "fancy indexing". The result is not an OrderedSet because you may ask
+ for duplicate indices, and the number of elements returned should be
+ the number of elements asked for.
+
+ Example:
+ >>> oset = OrderedSet([1, 2, 3])
+ >>> oset[1]
+ 2
+ """
+ if isinstance(index, slice) and index == SLICE_ALL:
+ return self.copy()
+ elif is_iterable(index):
+ return [self.items[i] for i in index]
+ elif hasattr(index, "__index__") or isinstance(index, slice):
+ result = self.items[index]
+ if isinstance(result, list):
+ return self.__class__(result)
+ else:
+ return result
+ else:
+ raise TypeError("Don't know how to index an OrderedSet by %r" % index)
+
+ def copy(self):
+ """
+ Return a shallow copy of this object.
+
+ Example:
+ >>> this = OrderedSet([1, 2, 3])
+ >>> other = this.copy()
+ >>> this == other
+ True
+ >>> this is other
+ False
+ """
+ return self.__class__(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):
+ """
+ Test if the item is in this ordered set
+
+ Example:
+ >>> 1 in OrderedSet([1, 3, 2])
+ True
+ >>> 5 in OrderedSet([1, 3, 2])
+ False
+ """
+ return key in self.map
+
+ 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.
+
+ Example:
+ >>> oset = OrderedSet()
+ >>> oset.append(3)
+ 0
+ >>> print(oset)
+ OrderedSet([3])
+ """
+ if key not in self.map:
+ self.map[key] = len(self.items)
+ self.items.append(key)
+ return self.map[key]
+
+ append = add
+
+ def update(self, sequence):
+ """
+ Update the set with the given iterable sequence, then return the index
+ of the last element inserted.
+
+ Example:
+ >>> oset = OrderedSet([1, 2, 3])
+ >>> oset.update([3, 1, 5, 1, 4])
+ 4
+ >>> print(oset)
+ OrderedSet([1, 2, 3, 5, 4])
+ """
+ item_index = None
+ try:
+ for item in sequence:
+ item_index = self.add(item)
+ except TypeError:
+ raise ValueError(
+ "Argument needs to be an iterable, got %s" % type(sequence)
+ )
+ return item_index
+
+ def index(self, key):
+ """
+ Get the index of a given entry, raising an IndexError if it's not
+ present.
+
+ `key` can be an iterable of entries that is not a string, in which case
+ this returns a list of indices.
+
+ Example:
+ >>> oset = OrderedSet([1, 2, 3])
+ >>> oset.index(2)
+ 1
+ """
+ if is_iterable(key):
+ return [self.index(subkey) for subkey in key]
+ return self.map[key]
+
+ # Provide some compatibility with pd.Index
+ get_loc = index
+ get_indexer = index
+
+ def pop(self):
+ """
+ Remove and return the last element from the set.
+
+ Raises KeyError if the set is empty.
+
+ Example:
+ >>> oset = OrderedSet([1, 2, 3])
+ >>> oset.pop()
+ 3
+ """
+ if not self.items:
+ raise KeyError("Set is empty")
+
+ elem = self.items[-1]
+ del self.items[-1]
+ del self.map[elem]
+ return elem
+
+ def discard(self, key):
+ """
+ Remove an element. Do not raise an exception if absent.
+
+ The MutableSet mixin uses this to implement the .remove() method, which
+ *does* raise an error when asked to remove a non-existent item.
+
+ Example:
+ >>> oset = OrderedSet([1, 2, 3])
+ >>> oset.discard(2)
+ >>> print(oset)
+ OrderedSet([1, 3])
+ >>> oset.discard(2)
+ >>> print(oset)
+ OrderedSet([1, 3])
+ """
+ if key in self:
+ i = self.map[key]
+ del self.items[i]
+ del self.map[key]
+ for k, v in self.map.items():
+ if v >= i:
+ self.map[k] = v - 1
+
+ def clear(self):
+ """
+ Remove all items from this OrderedSet.
+ """
+ del self.items[:]
+ self.map.clear()
+
+ def __iter__(self):
+ """
+ Example:
+ >>> list(iter(OrderedSet([1, 2, 3])))
+ [1, 2, 3]
+ """
+ return iter(self.items)
+
+ def __reversed__(self):
+ """
+ Example:
+ >>> list(reversed(OrderedSet([1, 2, 3])))
+ [3, 2, 1]
+ """
+ return reversed(self.items)
+
+ def __repr__(self):
+ if not self:
+ return "%s()" % (self.__class__.__name__,)
+ return "%s(%r)" % (self.__class__.__name__, list(self))
+
+ def __eq__(self, other):
+ """
+ Returns true if the containers have the same items. If `other` is a
+ Sequence, then order is checked, otherwise it is ignored.
+
+ Example:
+ >>> oset = OrderedSet([1, 3, 2])
+ >>> oset == [1, 3, 2]
+ True
+ >>> oset == [1, 2, 3]
+ False
+ >>> oset == [2, 3]
+ False
+ >>> oset == OrderedSet([3, 2, 1])
+ False
+ """
+ # In Python 2 deque is not a Sequence, so treat it as one for
+ # consistent behavior with Python 3.
+ if isinstance(other, (Sequence, deque)):
+ # Check that this OrderedSet contains the same elements, in the
+ # same order, as the other object.
+ return list(self) == list(other)
+ 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
+
+ def union(self, *sets):
+ """
+ Combines all unique items.
+ Each items order is defined by its first appearance.
+
+ Example:
+ >>> oset = OrderedSet.union(OrderedSet([3, 1, 4, 1, 5]), [1, 3], [2, 0])
+ >>> print(oset)
+ OrderedSet([3, 1, 4, 5, 2, 0])
+ >>> oset.union([8, 9])
+ OrderedSet([3, 1, 4, 5, 2, 0, 8, 9])
+ >>> oset | {10}
+ OrderedSet([3, 1, 4, 5, 2, 0, 10])
+ """
+ cls = self.__class__ if isinstance(self, OrderedSet) else OrderedSet
+ containers = map(list, it.chain([self], sets))
+ items = it.chain.from_iterable(containers)
+ return cls(items)
+
+ def __and__(self, other):
+ # the parent implementation of this is backwards
+ return self.intersection(other)
+
+ def intersection(self, *sets):
+ """
+ Returns elements in common between all sets. Order is defined only
+ by the first set.
+
+ Example:
+ >>> oset = OrderedSet.intersection(OrderedSet([0, 1, 2, 3]), [1, 2, 3])
+ >>> print(oset)
+ OrderedSet([1, 2, 3])
+ >>> oset.intersection([2, 4, 5], [1, 2, 3, 4])
+ OrderedSet([2])
+ >>> oset.intersection()
+ OrderedSet([1, 2, 3])
+ """
+ cls = self.__class__ if isinstance(self, OrderedSet) else OrderedSet
+ if sets:
+ common = set.intersection(*map(set, sets))
+ items = (item for item in self if item in common)
+ else:
+ items = self
+ return cls(items)
+
+ def difference(self, *sets):
+ """
+ Returns all elements that are in this set but not the others.
+
+ Example:
+ >>> OrderedSet([1, 2, 3]).difference(OrderedSet([2]))
+ OrderedSet([1, 3])
+ >>> OrderedSet([1, 2, 3]).difference(OrderedSet([2]), OrderedSet([3]))
+ OrderedSet([1])
+ >>> OrderedSet([1, 2, 3]) - OrderedSet([2])
+ OrderedSet([1, 3])
+ >>> OrderedSet([1, 2, 3]).difference()
+ OrderedSet([1, 2, 3])
+ """
+ cls = self.__class__
+ if sets:
+ other = set.union(*map(set, sets))
+ items = (item for item in self if item not in other)
+ else:
+ items = self
+ return cls(items)
+
+ def issubset(self, other):
+ """
+ Report whether another set contains this set.
+
+ Example:
+ >>> OrderedSet([1, 2, 3]).issubset({1, 2})
+ False
+ >>> OrderedSet([1, 2, 3]).issubset({1, 2, 3, 4})
+ True
+ >>> OrderedSet([1, 2, 3]).issubset({1, 4, 3, 5})
+ False
+ """
+ if len(self) > len(other): # Fast check for obvious cases
+ return False
+ return all(item in other for item in self)
+
+ def issuperset(self, other):
+ """
+ Report whether this set contains another set.
+
+ Example:
+ >>> OrderedSet([1, 2]).issuperset([1, 2, 3])
+ False
+ >>> OrderedSet([1, 2, 3, 4]).issuperset({1, 2, 3})
+ True
+ >>> OrderedSet([1, 4, 3, 5]).issuperset({1, 2, 3})
+ False
+ """
+ if len(self) < len(other): # Fast check for obvious cases
+ return False
+ return all(item in self for item in other)
+
+ def symmetric_difference(self, other):
+ """
+ Return the symmetric difference of two OrderedSets as a new set.
+ That is, the new set will contain all elements that are in exactly
+ one of the sets.
+
+ Their order will be preserved, with elements from `self` preceding
+ elements from `other`.
+
+ Example:
+ >>> this = OrderedSet([1, 4, 3, 5, 7])
+ >>> other = OrderedSet([9, 7, 1, 3, 2])
+ >>> this.symmetric_difference(other)
+ OrderedSet([4, 5, 9, 2])
+ """
+ cls = self.__class__ if isinstance(self, OrderedSet) else OrderedSet
+ diff1 = cls(self).difference(other)
+ diff2 = cls(other).difference(self)
+ return diff1.union(diff2)
+
+ def _update_items(self, items):
+ """
+ Replace the 'items' list of this OrderedSet with a new one, updating
+ self.map accordingly.
+ """
+ self.items = items
+ self.map = {item: idx for (idx, item) in enumerate(items)}
+
+ def difference_update(self, *sets):
+ """
+ Update this OrderedSet to remove items from one or more other sets.
+
+ Example:
+ >>> this = OrderedSet([1, 2, 3])
+ >>> this.difference_update(OrderedSet([2, 4]))
+ >>> print(this)
+ OrderedSet([1, 3])
+
+ >>> this = OrderedSet([1, 2, 3, 4, 5])
+ >>> this.difference_update(OrderedSet([2, 4]), OrderedSet([1, 4, 6]))
+ >>> print(this)
+ OrderedSet([3, 5])
+ """
+ items_to_remove = set()
+ for other in sets:
+ items_to_remove |= set(other)
+ self._update_items([item for item in self.items if item not in items_to_remove])
+
+ def intersection_update(self, other):
+ """
+ Update this OrderedSet to keep only items in another set, preserving
+ their order in this set.
+
+ Example:
+ >>> this = OrderedSet([1, 4, 3, 5, 7])
+ >>> other = OrderedSet([9, 7, 1, 3, 2])
+ >>> this.intersection_update(other)
+ >>> print(this)
+ OrderedSet([1, 3, 7])
+ """
+ other = set(other)
+ self._update_items([item for item in self.items if item in other])
+
+ def symmetric_difference_update(self, other):
+ """
+ Update this OrderedSet to remove items from another set, then
+ add items from the other set that were not present in this set.
+
+ Example:
+ >>> this = OrderedSet([1, 4, 3, 5, 7])
+ >>> other = OrderedSet([9, 7, 1, 3, 2])
+ >>> this.symmetric_difference_update(other)
+ >>> print(this)
+ OrderedSet([4, 5, 9, 2])
+ """
+ items_to_add = [item for item in other if item not in self]
+ items_to_remove = set(other)
+ self._update_items(
+ [item for item in self.items if item not in items_to_remove] + items_to_add
+ )
projects / platform / upstream / python-setuptools.git / commitdiff