From ae2198bd955530c61dd1f4cd99f23c7a0c069b6e Mon Sep 17 00:00:00 2001
From: Eugen Rochko <eugen@zeonfederated.com>
Date: Sat, 25 Jan 2020 16:00:29 +0100
Subject: [PATCH] Fix validations of reactions limit (#12955)

---
 app/validators/reaction_validator.rb       | 10 ++++--
 spec/validators/reaction_validator_spec.rb | 42 ++++++++++++++++++++++
 2 files changed, 49 insertions(+), 3 deletions(-)
 create mode 100644 spec/validators/reaction_validator_spec.rb

diff --git a/app/validators/reaction_validator.rb b/app/validators/reaction_validator.rb
index be899c89d0..494b6041bf 100644
--- a/app/validators/reaction_validator.rb
+++ b/app/validators/reaction_validator.rb
@@ -6,10 +6,10 @@ class ReactionValidator < ActiveModel::Validator
   LIMIT = 8
 
   def validate(reaction)
-    return if reaction.name.blank? || reaction.custom_emoji_id.present?
+    return if reaction.name.blank?
 
-    reaction.errors.add(:name, I18n.t('reactions.errors.unrecognized_emoji')) unless unicode_emoji?(reaction.name)
-    reaction.errors.add(:base, I18n.t('reactions.errors.limit_reached')) if limit_reached?(reaction)
+    reaction.errors.add(:name, I18n.t('reactions.errors.unrecognized_emoji')) if reaction.custom_emoji_id.blank? && !unicode_emoji?(reaction.name)
+    reaction.errors.add(:base, I18n.t('reactions.errors.limit_reached')) if new_reaction?(reaction) && limit_reached?(reaction)
   end
 
   private
@@ -18,6 +18,10 @@ class ReactionValidator < ActiveModel::Validator
     SUPPORTED_EMOJIS.include?(name)
   end
 
+  def new_reaction?(reaction)
+    !reaction.announcement.announcement_reactions.where(name: reaction.name).exists?
+  end
+
   def limit_reached?(reaction)
     reaction.announcement.announcement_reactions.where.not(name: reaction.name).count('distinct name') >= LIMIT
   end
diff --git a/spec/validators/reaction_validator_spec.rb b/spec/validators/reaction_validator_spec.rb
new file mode 100644
index 0000000000..d73104cb69
--- /dev/null
+++ b/spec/validators/reaction_validator_spec.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe ReactionValidator do
+  let(:announcement) { Fabricate(:announcement) }
+
+  describe '#validate' do
+    it 'adds error when not a valid unicode emoji' do
+      reaction = announcement.announcement_reactions.build(name: 'F')
+      subject.validate(reaction)
+      expect(reaction.errors).to_not be_empty
+    end
+
+    it 'does not add error when non-unicode emoji is a custom emoji' do
+      custom_emoji = Fabricate(:custom_emoji)
+      reaction = announcement.announcement_reactions.build(name: custom_emoji.shortcode, custom_emoji_id: custom_emoji.id)
+      subject.validate(reaction)
+      expect(reaction.errors).to be_empty
+    end
+
+    it 'adds error when 8 reactions already exist' do
+      %w(🐘 ❤️ 🙉 😍 😋 😂 😞 👍).each do |name|
+        announcement.announcement_reactions.create!(name: name, account: Fabricate(:account))
+      end
+
+      reaction = announcement.announcement_reactions.build(name: '😘')
+      subject.validate(reaction)
+      expect(reaction.errors).to_not be_empty
+    end
+
+    it 'does not add error when new reaction is part of the existing ones' do
+      %w(🐘 ❤️ 🙉 😍 😋 😂 😞 👍).each do |name|
+        announcement.announcement_reactions.create!(name: name, account: Fabricate(:account))
+      end
+
+      reaction = announcement.announcement_reactions.build(name: '😋')
+      subject.validate(reaction)
+      expect(reaction.errors).to be_empty
+    end
+  end
+end