def test_remove_by_first_or_second(self):
""" Tests for removing elements from the biDict """
pair_first = (1, 'one')
pair_second = (2, 'two')
bidict = BiDict(pair_first, pair_second)
bidict._remove_by_first(pair_first[0])
bidict._remove_by_second(pair_second[1])
missing_first = 0
missing_second = 0
try:
bidict._get_by_first(pair_first[0])
except KeyError:
missing_first += 1
try:
bidict._get_by_first(pair_second[0])
except KeyError:
missing_first += 1
try:
bidict._get_by_second(pair_first[1])
except KeyError:
missing_second += 1
try:
bidict._get_by_second(pair_second[1])
except KeyError:
missing_second += 1
self.assertEqual(missing_first, 2)
self.assertEqual(missing_second, 2)
def test_remove_by_first_or_second(self):
'''
Tests for removing elements from the biDict
'''
pair_first = (1, 'one')
pair_second = (2, 'two')
bidict = BiDict(pair_first, pair_second)
bidict._remove_by_first(pair_first[0])
bidict._remove_by_second(pair_second[1])
missing_first = 0
missing_second = 0
try:
bidict._get_by_first(pair_first[0])
except KeyError:
missing_first += 1
try:
bidict._get_by_first(pair_second[0])
except KeyError:
missing_first += 1
try:
bidict._get_by_second(pair_first[1])
except KeyError:
missing_second += 1
try:
bidict._get_by_second(pair_second[1])
except KeyError:
missing_second += 1
self.assertEqual(missing_first, 2)
self.assertEqual(missing_second, 2)
class TwoKeyDict(object):
'''
It's a standard Dictionary with a secondary key.
For example, you can add an element ('2', 'II', two'), where the
first two arguments are keys and the third is the stored object, and access
it as::
twokey['2'] ==> 'two'
twokey['II'] ==> 'two'
You can also request the other key, given one.
Function calls start with _ because you'll probably want to rename them
when you use this dictionary, for the sake of clarity.
'''
def __init__(self, *triplets):
'''
Creates the TwoKeyDict and optionally populates it with some data
@param triplets: tuples for populating the TwoKeyDict. Format:
((key1, key2, data_to_store), ...)
'''
super(TwoKeyDict, self).__init__()
self._key_to_key_bidict = BiDict()
self._primary_to_value = {}
for triplet in triplets:
self.add(triplet)
def add(self, triplet):
'''
Adds a new triplet to the TwoKeyDict
@param triplet: a tuple formatted like this:
(key1, key2, data_to_store)
'''
self._key_to_key_bidict.add((triplet[0], triplet[1]))
self._primary_to_value[triplet[0]] = triplet[2]
def _get_by_primary(self, primary):
'''
Gets the stored data given the primary key
@param primary: the primary key
@returns object: the stored object
'''
return self._primary_to_value[primary]
def _get_by_secondary(self, secondary):
'''
Gets the stored data given the secondary key
@param secondary: the primary key
@returns object: the stored object
'''
primary = self._key_to_key_bidict._get_by_second(secondary)
return self._get_by_primary(primary)
def _remove_by_primary(self, primary):
'''
Removes a triplet given the rpimary key.
@param primary: the primary key
'''
del self._primary_to_value[primary]
self._key_to_key_bidict._remove_by_first(primary)
def _remove_by_secondary(self, secondary):
'''
Removes a triplet given the rpimary key.
@param secondary: the primary key
'''
primary = self._key_to_key_bidict._get_by_second(secondary)
self._remove_by_primary(primary)
def _get_secondary_key(self, primary):
'''
Gets the secondary key given the primary
@param primary: the primary key
@returns object: the secondary key
'''
return self._key_to_key_bidict._get_by_first(primary)
def _get_primary_key(self, secondary):
'''
Gets the primary key given the secondary
@param secondary: the secondary key
@returns object: the primary key
'''
return self._key_to_key_bidict._get_by_second(secondary)
def _get_all_primary_keys(self):
'''
Returns all primary keys
@returns list: list of all primary keys
'''
return self._key_to_key_bidict._get_all_first()
def _get_all_secondary_keys(self):
'''
Returns all secondary keys
@returns list: list of all secondary keys
'''
return self._key_to_key_bidict._get_all_second()