def test_cgp_grey_animal_kingdom(self):
"""Tests CGP Grey example STV election 'Politics in the Animal Kingdom'
Link: https://www.youtube.com/watch?v=l8XOZJkozfI
Expected winners: Gorilla, Monkey, Tiger
"""
# Setup
tarsier = Candidate('tarsier', name='Tarsier')
gorilla = Candidate('gorilla', name='Gorilla')
monkey = Candidate('monkey', name='Monkey')
tiger = Candidate('tiger', name='Tiger')
lynx = Candidate('lynx', name='Lynx')
expected_winners = set([gorilla, monkey, tiger])
seats = 3
tiebreak_alphanumeric = 'abcdefghijklmnopqrstuvwxyz'
num_ballots = 10000
ballots = (
ballots_for_candidates([tarsier, gorilla], int(
.05 * num_ballots)) + ballots_for_candidates(
[gorilla, tarsier, monkey], int(.28 * num_ballots)) +
ballots_for_candidates([monkey], int(.33 * num_ballots)) +
ballots_for_candidates([tiger], int(.21 * num_ballots)) +
ballots_for_candidates([lynx, tiger, tarsier, monkey, gorilla],
int(.13 * num_ballots)))
# Test
election = Election(seats=seats,
ballots=ballots,
random_alphanumeric=tiebreak_alphanumeric)
results = election.compute_results()
self.assertEqual(expected_winners, results.candidates_elected)
def test_wikipedia_food_selection(self):
"""Tests Wikipedia's example STV election, using choices of food.
Link: https://en.wikipedia.org/wiki/Single_transferable_vote#Example
Expected winners: Chocolate, Oranges, Strawberries
"""
# Setup
chocolate = Candidate('chocolate', name='Chocolate')
oranges = Candidate('oranges', name='Oranges')
pears = Candidate('pears', name='Pears')
strawberries = Candidate('strawberries', name='Strawberries')
sweets = Candidate('sweets', name='Sweets')
expected_winners = set([chocolate, oranges, strawberries])
seats = 3
tiebreak_alphanumeric = 'abcdefghijklmnopqrstuvwxyz'
ballots = (ballots_for_candidates([oranges], 4) +
ballots_for_candidates([pears, oranges], 2) +
ballots_for_candidates([chocolate, strawberries], 8) +
ballots_for_candidates([chocolate, sweets], 4) +
ballots_for_candidates([strawberries], 1) +
ballots_for_candidates([sweets], 1))
# Test
election = Election(seats=seats,
ballots=ballots,
random_alphanumeric=tiebreak_alphanumeric)
results = election.compute_results()
self.assertEqual(expected_winners, results.candidates_elected)
def test_florida_2000_presidential(self):
"""Tests the 2000 Florida presidential election, scaled 1%.
An example of a election between two major candidates and a third-party.
For the sake of ranking votes, this test assumes that Nader supporters
prefer Gore to Bush by a 2:1 margin, which is not necessarily true.
Expected winners: Gore
Round 0
Ballots:
29127 * [Bush]
29122 * [Gore]
324 * [Nader, Bush]
649 * [Nader, Gore]
Votes:
Bush: 29127
Gore: 29122
Nader: 974
Threshold: (29127+29122+974) / (1+1) + 1 = 29612.5
Result: Nader is eliminated
Round 1
Ballots:
29452 * [Bush]
29972 * [Gore]
Votes:
Bush: 29452
Gore: 29972
Threshold: (29452+29972) / (1+1) + 1 = 29612.5
Result: Gore is elected
"""
# Setup
bush = Candidate('gbush', name='George Bush')
gore = Candidate('agore', name='Al Gore')
nader = Candidate('rnader', name='Ralph Nader')
expected_winners = set([gore])
seats = 1
tiebreak_alphanumeric = 'abcdefghijklmnopqrstuvwxyz'
ballots = (ballots_for_candidates([bush], 29127) +
ballots_for_candidates([gore], 29122) +
ballots_for_candidates([nader, bush], 324) +
ballots_for_candidates([nader, gore], 649))
# Test
election = Election(seats=seats,
ballots=ballots,
random_alphanumeric=tiebreak_alphanumeric)
results = election.compute_results()
self.assertEqual(expected_winners, results.candidates_elected)
def test_cgp_grey_stv_election_walkthrough(self):
"""Tests CGP Grey example STV election 'Extra: STV Election Walkthrough'
Link: https://www.youtube.com/watch?v=Ac9070OIMUg
Expected winners: Gorilla, Silverback, Owl, Turtle, Tiger
"""
# Setup
tarsier = Candidate('tarsier', name='Tarsier')
gorilla = Candidate('gorilla', name='Gorilla')
silverback = Candidate('silverback', name='Silverback')
owl = Candidate('owl', name='Owl')
turtle = Candidate('turtle', name='Turtle')
snake = Candidate('snake', name='Snake')
tiger = Candidate('tiger', name='Tiger')
lynx = Candidate('lynx', name='Lynx')
jackalope = Candidate('jackalope', name='Jackalope')
buffalo = Candidate('buffalo', name='Buffalo')
expected_winners = set([gorilla, silverback, owl, turtle, tiger])
seats = 5
tiebreak_alphanumeric = 'abcdefghijklmnopqrstuvwxyz'
num_ballots = 10000
ballots = (
ballots_for_candidates([tarsier, silverback], int(
.05 * num_ballots)) + ballots_for_candidates(
[gorilla, silverback], int(.21 * num_ballots)) +
ballots_for_candidates([gorilla, tarsier, silverback],
int(.11 * num_ballots)) +
ballots_for_candidates([silverback], int(.03 * num_ballots)) +
ballots_for_candidates([owl, turtle], int(.33 * num_ballots)) +
ballots_for_candidates([turtle], int(.01 * num_ballots)) +
ballots_for_candidates([snake, turtle], int(.01 * num_ballots)) +
ballots_for_candidates([tiger], int(.16 * num_ballots)) +
ballots_for_candidates([lynx, tiger], int(.04 * num_ballots)) +
ballots_for_candidates([jackalope], int(.02 * num_ballots)) +
ballots_for_candidates([buffalo, jackalope], int(
.02 * num_ballots)) + ballots_for_candidates(
[buffalo, jackalope, turtle], int(.01 * num_ballots)))
# Test
election = Election(seats=seats,
ballots=ballots,
random_alphanumeric=tiebreak_alphanumeric)
results = election.compute_results()
self.assertEqual(expected_winners, results.candidates_elected)
def castVote(self, vote):
for i in range(10):
vote = Vote(Voter("Bad Voter {}".format(i)),
Candidate("Bad Candidate"))
block = block(vote, self.chain.last)
# mostly invalid proof
proof = hash(block)
self.chain.addBlock(block, proof)
self.announceNewBlock()
return true
def setUp(self):
self.nCandidates = 3
self.nVoters = 10
self.nNodes = 5
self.candidates = [Candidate("Candidate %s" % i) for i in range(self.nCandidates)]
self.voters = [Voter("Voter %s" % i) for i in range(self.nVoters)]
self.network = Network()
for i in range(self.nNodes):
self.network.addNode()
def candidate_from_input(candidate_input):
"""Returns a Candidate representing the input string.
Args:
candidate_input: String representing user input for a Candidate. The
expected format is 'uid' or optionally 'uid (name)'.
Returns:
Candidate representing the input uid (and optionally name).
"""
if input_string_is_no_confidence(candidate_input):
return NoConfidence()
else:
expr = '(.*?)\s*\((.*?)\)'
regex = re.compile(expr)
result = regex.match(candidate_input)
if result is not None:
uid = result.group(1)
name = result.group(2)
else:
uid = candidate_input
name = None
return Candidate(uid, name=name)
def candidates_for_ids(candidate_ids):
"""Returns an ordered list of Candidates for an ordered list of ids.
This is helpful for tests where candidates on ballots can be defined as
short strings (i.e. 'A', 'B', 'NC') in the test cases, which can then be
converted to proper Candidates.
Args:
candidate_ids: List of strings representing candidate ids.
Returns:
List of Candidates corresponding to the given ids.
"""
candidate_for_id = {
'NC': NoConfidence(),
'A': Candidate('dgund', name='Devin Gund'),
'B': Candidate('gwashington', name='George Washington'),
'C': Candidate('jadams', name='John Adams'),
'D': Candidate('tjefferson', name='Thomas Jefferson'),
'E': Candidate('jmadison', name='James Madison'),
'F': Candidate('jmonroe', name='James Monroe'),
'G': Candidate('jqadams', name='John Quincy Adams'),
'H': Candidate('ajackson', name='Andrew Jackson'),
'I': Candidate('mvburen', name='Martin Van Buren'),
'J': Candidate('wharrison', name='William Harrison'),
'K': Candidate('jtyler', name='John Tyler'),
'L': Candidate('jpolk', name='James Polk'),
'M': Candidate('ztaylor', name='Zachary Taylor'),
'N': Candidate('mfillmore', name='Millard Fillmore'),
'O': Candidate('fpierce', name='Franklin Pierce'),
'P': Candidate('jbuchanan', name='James Buchanan'),
'Q': Candidate('alincoln', name='Abraham Lincoln'),
'R': Candidate('ajohnson', name='Andrew Johnson'),
'S': Candidate('ugrant', name='Ulysses Grant'),
'T': Candidate('rhayes', name='Rutherford Hayes'),
'U': Candidate('jgarfield', name='James Garfield'),
'V': Candidate('carthur', name='Chester Arthur'),
'W': Candidate('gcleveland', name='Grover Cleveland'),
'X': Candidate('bharrison', name='Benjamin Harrison'),
'Y': Candidate('wmckinley', name='William McKinley'),
'Z': Candidate('troosevelt', name='Theodore Roosevelt'),
}
candidates = []
for candidate_id in candidate_ids:
candidates.append(candidate_for_id[candidate_id])
return candidates
import unittest
from block import Block
from election import Vote, Voter, Candidate
from blockchain import Blockchain, InvalidBlockchain
# Voters
Amany = Voter("Amany")
Anthony = Voter("Anthony")
Owen = Voter("Owen")
# Candidates
James = Candidate("James")
Marcus = Candidate("Marcus")
Ronny = Candidate("Ronny")
ab = {
'jy': Vote(Amany, James),
'mc': Vote(Amany, Marcus),
'rk': Vote(Amany, Ronny)
}
ak = {
'jy': Vote(Anthony, James),
'mc': Vote(Anthony, Marcus),
'rk': Vote(Anthony, Ronny)
}
on = {
'jy': Vote(Owen, James),
'mc': Vote(Owen, Marcus),