From 56dd8bed5abf1ab2379cae2b891ce3b4b2c5e9b0 Mon Sep 17 00:00:00 2001
From: Joe Slag <joe@slagwerks.com>
Date: Mon, 19 Mar 2007 17:09:56 +0000
Subject: [PATCH] If a vote doesn't contain all possible candidates, assign all
 unspecified candidates the same position below ranked candidates

git-svn-id: svn://rubyforge.org/var/svn/rubyvote/trunk@17 1440c7f4-e209-0410-9a04-881b5eb134a8
---
 lib/rubyvote/condorcet.rb | 43 ++++++++++++++++++++++++---------------
 test/condorcet_test.rb    | 14 +++++++++++++
 2 files changed, 41 insertions(+), 16 deletions(-)

diff --git a/lib/rubyvote/condorcet.rb b/lib/rubyvote/condorcet.rb
index 5f103fb..f4ed7b7 100644
--- a/lib/rubyvote/condorcet.rb
+++ b/lib/rubyvote/condorcet.rb
@@ -36,29 +36,40 @@ class CondorcetVote < ElectionVote
   def tally_vote(vote=nil)
 
     vote.each_with_index do |winner, index|
-      # only run through this if this *is* preferred to something
-      break if vote.length - 1 == index
-      losers = vote.last( vote.length - index )
+      if vote.flatten.length < @candidates.length
+        implied_losers = @candidates.select { |c| not vote.include?(c) }
+        vote.push(implied_losers)
+      end
+      if vote.length - 1 == index
+        losers = []
+      else
+        losers = vote.last( vote.flatten.length - index )
+      end
 
-      losers.each do |loser|
-        next if winner == loser
+      losers.each do |place|
+        place = [place] unless place.class == Array
+        place.each do |loser|
+          
+          next if winner == loser
 
-        @votes[winner] = Hash.new unless @votes.has_key?(winner)
-        @votes[loser] = Hash.new unless @votes.has_key?(loser)
+          @votes[winner] = Hash.new unless @votes.has_key?(winner)
+          @votes[loser] = Hash.new unless @votes.has_key?(loser)
 
-        if @votes[winner].has_key?(loser)
-          @votes[winner][loser] += 1
-        else
-          @votes[winner][loser] = 1
-        end
+          if @votes[winner].has_key?(loser)
+            @votes[winner][loser] += 1
+          else
+            @votes[winner][loser] = 1
+          end
 
-        # make sure we have a comparable object
-        @votes[loser][winner] = 0 unless @votes[loser].has_key?( winner )
+          # make sure we have a comparable object
+          @votes[loser][winner] = 0 unless @votes[loser].has_key?( winner )
 
-        @candidates << loser unless @candidates.include?( loser )
+          @candidates << loser unless @candidates.include?( loser )
+        end
       end
 
-      @candidates << winner unless @candidates.include?( winner )
+      @candidates << winner unless @candidates.include?( winner ) || 
+        winner.class == Array
     end
   end
 
diff --git a/test/condorcet_test.rb b/test/condorcet_test.rb
index b0df865..c885a71 100644
--- a/test/condorcet_test.rb
+++ b/test/condorcet_test.rb
@@ -59,4 +59,18 @@ class TestCondorcetVote < Test::Unit::TestCase
     assert_equal [['B'], ['C'], ['D'], ['A']], 
                  CloneproofSSDVote.new(vote_array).result.get_full_results
   end
+
+  def test_ssd_incomplete_votes
+    vote_array = Array.new
+    3.times {vote_array << "ABCD".split("")}
+    2.times {vote_array << "DABC".split("")}
+    2.times {vote_array << "DBCA".split("")}
+    4.times {vote_array << ["C"]}
+    2.times {vote_array << "DBC".split("")}
+
+    assert_equal "B", CloneproofSSDVote.new(vote_array).result.winners[0]
+    assert_equal [['B'], ['C'], ['D'], ['A']], 
+                 CloneproofSSDVote.new(vote_array).result.get_full_results
+  end
+
 end
-- 
2.39.5