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- from __future__ import unicode_literals
- from __future__ import absolute_import
- from . import util
- from copy import deepcopy
-
-
- class OrderedDict(dict):
- """
- A dictionary that keeps its keys in the order in which they're inserted.
-
- Copied from Django's SortedDict with some modifications.
-
- """
- def __new__(cls, *args, **kwargs):
- instance = super(OrderedDict, cls).__new__(cls, *args, **kwargs)
- instance.keyOrder = []
- return instance
-
- def __init__(self, data=None):
- if data is None or isinstance(data, dict):
- data = data or []
- super(OrderedDict, self).__init__(data)
- self.keyOrder = list(data) if data else []
- else:
- super(OrderedDict, self).__init__()
- super_set = super(OrderedDict, self).__setitem__
- for key, value in data:
- # Take the ordering from first key
- if key not in self:
- self.keyOrder.append(key)
- # But override with last value in data (dict() does this)
- super_set(key, value)
-
- def __deepcopy__(self, memo):
- return self.__class__([(key, deepcopy(value, memo))
- for key, value in self.items()])
-
- def __copy__(self):
- # The Python's default copy implementation will alter the state
- # of self. The reason for this seems complex but is likely related to
- # subclassing dict.
- return self.copy()
-
- def __setitem__(self, key, value):
- if key not in self:
- self.keyOrder.append(key)
- super(OrderedDict, self).__setitem__(key, value)
-
- def __delitem__(self, key):
- super(OrderedDict, self).__delitem__(key)
- self.keyOrder.remove(key)
-
- def __iter__(self):
- return iter(self.keyOrder)
-
- def __reversed__(self):
- return reversed(self.keyOrder)
-
- def pop(self, k, *args):
- result = super(OrderedDict, self).pop(k, *args)
- try:
- self.keyOrder.remove(k)
- except ValueError:
- # Key wasn't in the dictionary in the first place. No problem.
- pass
- return result
-
- def popitem(self):
- result = super(OrderedDict, self).popitem()
- self.keyOrder.remove(result[0])
- return result
-
- def _iteritems(self):
- for key in self.keyOrder:
- yield key, self[key]
-
- def _iterkeys(self):
- for key in self.keyOrder:
- yield key
-
- def _itervalues(self):
- for key in self.keyOrder:
- yield self[key]
-
- if util.PY3: # pragma: no cover
- items = _iteritems
- keys = _iterkeys
- values = _itervalues
- else: # pragma: no cover
- iteritems = _iteritems
- iterkeys = _iterkeys
- itervalues = _itervalues
-
- def items(self):
- return [(k, self[k]) for k in self.keyOrder]
-
- def keys(self):
- return self.keyOrder[:]
-
- def values(self):
- return [self[k] for k in self.keyOrder]
-
- def update(self, dict_):
- for k in dict_:
- self[k] = dict_[k]
-
- def setdefault(self, key, default):
- if key not in self:
- self.keyOrder.append(key)
- return super(OrderedDict, self).setdefault(key, default)
-
- def value_for_index(self, index):
- """Returns the value of the item at the given zero-based index."""
- return self[self.keyOrder[index]]
-
- def insert(self, index, key, value):
- """Inserts the key, value pair before the item with the given index."""
- if key in self.keyOrder:
- n = self.keyOrder.index(key)
- del self.keyOrder[n]
- if n < index:
- index -= 1
- self.keyOrder.insert(index, key)
- super(OrderedDict, self).__setitem__(key, value)
-
- def copy(self):
- """Returns a copy of this object."""
- # This way of initializing the copy means it works for subclasses, too.
- return self.__class__(self)
-
- def __repr__(self):
- """
- Replaces the normal dict.__repr__ with a version that returns the keys
- in their Ordered order.
- """
- return '{%s}' % ', '.join(
- ['%r: %r' % (k, v) for k, v in self._iteritems()]
- )
-
- def clear(self):
- super(OrderedDict, self).clear()
- self.keyOrder = []
-
- def index(self, key):
- """ Return the index of a given key. """
- try:
- return self.keyOrder.index(key)
- except ValueError:
- raise ValueError("Element '%s' was not found in OrderedDict" % key)
-
- def index_for_location(self, location):
- """ Return index or None for a given location. """
- if location == '_begin':
- i = 0
- elif location == '_end':
- i = None
- elif location.startswith('<') or location.startswith('>'):
- i = self.index(location[1:])
- if location.startswith('>'):
- if i >= len(self):
- # last item
- i = None
- else:
- i += 1
- else:
- raise ValueError('Not a valid location: "%s". Location key '
- 'must start with a ">" or "<".' % location)
- return i
-
- def add(self, key, value, location):
- """ Insert by key location. """
- i = self.index_for_location(location)
- if i is not None:
- self.insert(i, key, value)
- else:
- self.__setitem__(key, value)
-
- def link(self, key, location):
- """ Change location of an existing item. """
- n = self.keyOrder.index(key)
- del self.keyOrder[n]
- try:
- i = self.index_for_location(location)
- if i is not None:
- self.keyOrder.insert(i, key)
- else:
- self.keyOrder.append(key)
- except Exception as e:
- # restore to prevent data loss and reraise
- self.keyOrder.insert(n, key)
- raise e
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