adds already supported proposals

spec/helpers/votes_helper_spec.rb

@@ -0,0 +1,21 @@
+require 'rails_helper'
+
+describe VotesHelper do
+
+  describe "#voted_for?" do
+    it "should return true if voted for a proposal" do
+      proposal = create(:proposal)
+      votes = {proposal.id => true}
+
+      expect(voted_for?(votes, proposal)).to eq(true)
+    end
+
+    it "should return false if not voted for a proposals" do
+      proposal = create(:proposal)
+      votes = {proposal.id => nil}
+
+      expect(voted_for?(votes, proposal)).to eq(false)
+    end
+  end
+
+end