FIX: count emoji shortcuts in topic title

https://meta.discourse.org/t/max-emojis-in-title-set-to-0-conflicting-with-emoji-shortcuts/98368/3?u=techapj

config/locales/server.en.yml

@@ -139,6 +139,7 @@ en:
       odd: must be odd
       record_invalid: ! 'Validation failed: %{errors}'
       max_emojis: "can't have more than %{max_emojis_count} emoji"
+      emojis_disabled: "can't have emoji"
       ip_address_already_screened: "is already included in an existing rule"
       restrict_dependent_destroy:
         one: "Cannot delete record because a dependent %{record} exists"

lib/validators/max_emojis_validator.rb

@@ -1,9 +1,10 @@
 class MaxEmojisValidator < ActiveModel::EachValidator
 
   def validate_each(record, attribute, value)
-    if Emoji.unicode_unescape(value).scan(/:([\w\-+]+(?::t\d)?):/).size > SiteSetting.max_emojis_in_title
+    unescaped_title = PrettyText.unescape_emoji(Emoji.unicode_unescape(CGI::escapeHTML(value)))
+    if unescaped_title.scan(/<img.+?class\s*=\s*'(emoji|emoji emoji-custom)'/).size > SiteSetting.max_emojis_in_title
       record.errors.add(
-        attribute, :max_emojis,
+        attribute, SiteSetting.max_emojis_in_title > 0 ? :max_emojis : :emojis_disabled,
         max_emojis_count: SiteSetting.max_emojis_in_title
       )
     end

spec/components/validators/max_emojis_validator_spec.rb

@@ -14,7 +14,7 @@ describe MaxEmojisValidator do
   shared_examples "validating any topic title" do
     it 'adds an error when emoji count is greater than SiteSetting.max_emojis_in_title' do
       SiteSetting.max_emojis_in_title = 3
-      record.title = '🧐 Lots of emojis here 🎃 :joy: :sunglasses:'
+      record.title = '🧐 Lots of emojis here 🎃 :joy: :)'
       validate
       expect(record.errors[:title][0]).to eq(I18n.t("errors.messages.max_emojis", max_emojis_count: 3))