From 43c0111ca156b99881cf5e489c1364a4c3ef5b90 Mon Sep 17 00:00:00 2001
From: Sam <sam.saffron@gmail.com>
Date: Mon, 14 Aug 2017 15:33:47 -0400
Subject: [PATCH] FIX: multichoice poll with more than 25 votes

In the past we would double up on avatars due to incorrect logic for
handling offset
---
 plugins/poll/lib/polls_updater.rb             |  2 +-
 plugins/poll/plugin.rb                        | 17 ++++++++--
 .../spec/controllers/polls_controller_spec.rb | 31 +++++++++++++++++++
 3 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/plugins/poll/lib/polls_updater.rb b/plugins/poll/lib/polls_updater.rb
index 488331041b1..ec5b250579b 100644
--- a/plugins/poll/lib/polls_updater.rb
+++ b/plugins/poll/lib/polls_updater.rb
@@ -130,7 +130,7 @@ module DiscoursePoll
     private
 
     def self.private_to_public_poll?(post, previous_polls, current_polls, poll_name)
-      previous_poll = previous_polls[poll_name]
+      _previous_poll = previous_polls[poll_name]
       current_poll = current_polls[poll_name]
 
       if previous_polls["public"].nil? && current_poll["public"] == "true"
diff --git a/plugins/poll/plugin.rb b/plugins/poll/plugin.rb
index c8d0cf8d051..cd426235365 100644
--- a/plugins/poll/plugin.rb
+++ b/plugins/poll/plugin.rb
@@ -220,17 +220,26 @@ after_initialize do
       poll = post.custom_fields[DiscoursePoll::POLLS_CUSTOM_FIELD][poll_name]
       raise Discourse::InvalidParameters.new("poll_name is invalid") if !poll
 
+      voter_limit = (params[:voter_limit] || 25).to_i
+      voter_limit = 0 if voter_limit < 0
+      voter_limit = 50 if voter_limit > 50
+
       user_ids = []
       options = poll["options"]
 
       if poll["type"] != "number"
+
+        per_option_voters = {}
+
         options.each do |option|
           if (params[:option_id])
             next unless option["id"] == params[:option_id].to_s
           end
 
           next unless option["voter_ids"]
-          user_ids << option["voter_ids"].slice((params[:offset].to_i || 0) * 25, 25)
+          voters = option["voter_ids"].slice((params[:offset].to_i || 0) * voter_limit, voter_limit)
+          per_option_voters[option["id"]] = Set.new(voters)
+          user_ids << voters
         end
 
         user_ids.flatten!
@@ -248,6 +257,10 @@ after_initialize do
               next unless option_id == params[:option_id].to_s
             end
 
+            voters = per_option_voters[option_id]
+            # we may have a user from a different vote
+            next unless voters.include?(user.id)
+
             result[option_id] ||= []
             result[option_id] << user_hash
           end
@@ -256,7 +269,7 @@ after_initialize do
         user_ids = options.map { |option| option["voter_ids"] }.sort!
         user_ids.flatten!
         user_ids.uniq!
-        user_ids = user_ids.slice((params[:offset].to_i || 0) * 25, 25)
+        user_ids = user_ids.slice((params[:offset].to_i || 0) * voter_limit, voter_limit)
 
         result = []
 
diff --git a/plugins/poll/spec/controllers/polls_controller_spec.rb b/plugins/poll/spec/controllers/polls_controller_spec.rb
index 02db8bdf930..d2d671b0e28 100644
--- a/plugins/poll/spec/controllers/polls_controller_spec.rb
+++ b/plugins/poll/spec/controllers/polls_controller_spec.rb
@@ -7,6 +7,7 @@ describe ::DiscoursePoll::PollsController do
   let!(:user) { log_in }
   let(:topic) { Fabricate(:topic) }
   let(:poll)  { Fabricate(:post, topic_id: topic.id, user_id: user.id, raw: "[poll]\n- A\n- B\n[/poll]") }
+  let(:multi_poll)  { Fabricate(:post, topic_id: topic.id, user_id: user.id, raw: "[poll min=1 max=2 type=multiple public=true]\n- A\n- B\n[/poll]") }
 
   describe "#vote" do
 
@@ -173,4 +174,34 @@ describe ::DiscoursePoll::PollsController do
     end
 
   end
+
+  describe "votes" do
+
+    it "correctly handles offset" do
+
+      first = "5c24fc1df56d764b550ceae1b9319125"
+      second = "e89dec30bbd9bf50fabf6a05b4324edf"
+
+      user1 = log_in
+      xhr :put, :vote, post_id: multi_poll.id, poll_name: "poll", options: [first]
+
+      user2 = log_in
+      xhr :put, :vote, post_id: multi_poll.id, poll_name: "poll", options: [first]
+
+      user3 = log_in
+      xhr :put, :vote,
+        post_id: multi_poll.id,
+        poll_name: "poll",
+        options: [first, second]
+
+      xhr :get, :voters, poll_name: 'poll', post_id: multi_poll.id, voter_limit: 2
+      json = JSON.parse(response.body)
+
+      # no user3 cause voter_limit is 2
+      expect(json["poll"][first].map { |h| h["id"] }.sort).to eq([user1.id, user2.id])
+      expect(json["poll"][second].map { |h| h["id"] }).to eq([user3.id])
+    end
+
+  end
+
 end