Fix validations of reactions limit (#12955)

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

spec/validators/reaction_validator_spec.rb

+# 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