From e29e0c049e6899f153a24ba9e191447d8011645b Mon Sep 17 00:00:00 2001
From: Washington Botelho <wbotelhos@gmail.com>
Date: Thu, 8 Feb 2018 18:37:13 -0200
Subject: [PATCH] fix: avoid error when has no rate record

---
 lib/rating/models/rating/rating.rb       |  2 +-
 spec/models/rating/update_rating_spec.rb | 22 ++++++++++++++++++++--
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/lib/rating/models/rating/rating.rb b/lib/rating/models/rating/rating.rb
index 1a441f9..a5c4dfa 100644
--- a/lib/rating/models/rating/rating.rb
+++ b/lib/rating/models/rating/rating.rb
@@ -101,7 +101,7 @@ module Rating
         count = distinct ? 'COUNT(DISTINCT resource_id)' : 'COUNT(1)'
 
         %((
-          SELECT #{count}
+          SELECT GREATEST(#{count}, 1)
           FROM #{rate_table_name}
           WHERE resource_type = :resource_type AND #{scope_type_query(scopeable)}
         ))
diff --git a/spec/models/rating/update_rating_spec.rb b/spec/models/rating/update_rating_spec.rb
index d339580..1dc8992 100644
--- a/spec/models/rating/update_rating_spec.rb
+++ b/spec/models/rating/update_rating_spec.rb
@@ -4,9 +4,9 @@ require 'rails_helper'
 require 'support/shared_context/with_database_records'
 
 RSpec.describe Rating::Rating, ':update_rating' do
-  include_context 'with_database_records'
-
   context 'with no scopeable' do
+    include_context 'with_database_records'
+
     it 'updates the rating data of the given resource' do
       record = described_class.find_by(resource: article_1)
 
@@ -18,6 +18,8 @@ RSpec.describe Rating::Rating, ':update_rating' do
   end
 
   context 'with scopeable' do
+    include_context 'with_database_records'
+
     it 'updates the rating data of the given resource respecting the scope' do
       record = described_class.find_by(resource: article_1, scopeable: category)
 
@@ -27,4 +29,20 @@ RSpec.describe Rating::Rating, ':update_rating' do
       expect(record.total).to    eq 2
     end
   end
+
+  context 'when rate table has no record' do
+    let!(:resource) { create :article }
+    let!(:scope)    { nil }
+
+    it 'calculates with counts values as zero' do
+      described_class.update_rating resource, scope
+
+      record = described_class.last
+
+      expect(record.average).to  eq 0
+      expect(record.estimate).to eq 0
+      expect(record.sum).to      eq 0
+      expect(record.total).to    eq 0
+    end
+  end
 end