Add emoji shortcode support

AGENTS.md

@@ -75,3 +75,8 @@ Blue-green deployment via GitHub Actions. Docker multi-arch images (amd64 + arm6
 **Production env vars:** `SECRET_KEY_BASE`, `VAPID_PUBLIC_KEY`, `VAPID_PRIVATE_KEY`, `SSL_DOMAIN` (or `DISABLE_SSL`), `SENTRY_DSN`
 
 **Data persistence:** Mount volume to `/rails/storage` (SQLite DB + file attachments)
+
+## Pull Request Guidelines
+
+- Do not include a "Test plan" section in PR descriptions
+- Keep PR descriptions concise with a summary of changes

Gemfile

@@ -45,6 +45,7 @@ gem "kredis"
 gem "platform_agent"
 gem "thruster"
 gem "redcarpet"
+gem "gemoji"
 
 group :development, :test do
   gem "debug"
@@ -55,6 +56,7 @@ end
 
 group :test do
   gem "capybara"
+  gem "minitest", "< 6.0"  # Rails doesn't yet support minitest 6.0's API changes
   gem "mocha"
   gem "selenium-webdriver"
   gem "webmock", require: false

Gemfile.lock

@@ -172,6 +172,7 @@ GEM
     geared_pagination (1.2.0)
       activesupport (>= 5.0)
       addressable (>= 2.5.0)
+    gemoji (4.1.0)
     globalid (1.3.0)
       activesupport (>= 6.1)
     hashdiff (1.2.0)
@@ -212,8 +213,7 @@ GEM
     mini_magick (5.3.1)
       logger
     mini_mime (1.1.5)
-    minitest (6.0.1)
-      prism (~> 1.5)
+    minitest (5.27.0)
     mocha (2.7.1)
       ruby2_keywords (>= 0.0.5)
     mono_logger (1.1.2)
@@ -418,10 +418,12 @@ DEPENDENCIES
   debug
   faker
   geared_pagination
+  gemoji
   image_processing (>= 1.2)
   importmap-rails!
   jbuilder
   kredis
+  minitest (< 6.0)
   mocha
   net-http-persistent
   ostruct

app/models/message.rb

@@ -1,5 +1,5 @@
 class Message < ApplicationRecord
-  include Attachment, Broadcasts, Mentionee, Pagination, Searchable
+  include Attachment, Broadcasts, Emojification, Mentionee, Pagination, Searchable
 
   belongs_to :room, touch: true
   belongs_to :creator, class_name: "User", default: -> { Current.user }

app/models/message/emojification.rb

@@ -0,0 +1,23 @@
+module Message::Emojification
+  extend ActiveSupport::Concern
+
+  EMOJI_SHORTCODE_PATTERN = /:([a-z0-9_+-]+):/i
+
+  included do
+    before_save :emojify_body, if: -> { body.changed? }
+  end
+
+  private
+    def emojify_body
+      return unless body.body.present?
+
+      html = body.body.to_html
+      emojified_html = html.gsub(EMOJI_SHORTCODE_PATTERN) do |match|
+        shortcode = $1.downcase
+        emoji = Emoji.find_by_alias(shortcode)
+        emoji ? emoji.raw : match
+      end
+
+      self.body = emojified_html if html != emojified_html
+    end
+end

test/models/message/emojification_test.rb

@@ -0,0 +1,84 @@
+require "test_helper"
+
+class Message::EmojificationTest < ActiveSupport::TestCase
+  test "converts shortcode to emoji on create" do
+    message = rooms(:designers).messages.create!(
+      body: "I :heart: this!",
+      client_message_id: "emoji-create",
+      creator: users(:david)
+    )
+
+    assert_includes message.body.body.to_html, "\u2764"
+    assert_not_includes message.body.body.to_html, ":heart:"
+  end
+
+  test "converts shortcode to emoji on update" do
+    message = rooms(:designers).messages.create!(
+      body: "Hello world",
+      client_message_id: "emoji-update",
+      creator: users(:david)
+    )
+
+    message.update!(body: "Hello :wave:")
+
+    assert_includes message.body.body.to_html, "\u{1F44B}"
+    assert_not_includes message.body.body.to_html, ":wave:"
+  end
+
+  test "preserves unknown shortcodes" do
+    message = rooms(:designers).messages.create!(
+      body: "This is :notarealcode: right?",
+      client_message_id: "emoji-unknown",
+      creator: users(:david)
+    )
+
+    assert_includes message.body.body.to_html, ":notarealcode:"
+  end
+
+  test "converts multiple occurrences of same shortcode" do
+    message = rooms(:designers).messages.create!(
+      body: ":heart: and :heart: and :heart:",
+      client_message_id: "emoji-multiple",
+      creator: users(:david)
+    )
+
+    assert_equal 3, message.body.body.to_html.scan("\u2764").count
+    assert_not_includes message.body.body.to_html, ":heart:"
+  end
+
+  test "case insensitive matching" do
+    message = rooms(:designers).messages.create!(
+      body: ":HEART: and :Heart: and :heart:",
+      client_message_id: "emoji-case",
+      creator: users(:david)
+    )
+
+    assert_equal 3, message.body.body.to_html.scan("\u2764").count
+    assert_not_includes message.body.body.to_html, ":HEART:"
+    assert_not_includes message.body.body.to_html, ":Heart:"
+    assert_not_includes message.body.body.to_html, ":heart:"
+  end
+
+  test "converts shortcodes within HTML content" do
+    message = rooms(:designers).messages.create!(
+      body: "<div>Check this :thumbsup:</div>",
+      client_message_id: "emoji-html",
+      creator: users(:david)
+    )
+
+    assert_includes message.body.body.to_html, "\u{1F44D}"
+    assert_not_includes message.body.body.to_html, ":thumbsup:"
+  end
+
+  test "converts multiple different shortcodes" do
+    message = rooms(:designers).messages.create!(
+      body: ":heart: :thumbsup: :100:",
+      client_message_id: "emoji-different",
+      creator: users(:david)
+    )
+
+    assert_includes message.body.body.to_html, "\u2764"
+    assert_includes message.body.body.to_html, "\u{1F44D}"
+    assert_includes message.body.body.to_html, "\u{1F4AF}"
+  end
+end

test/test_helper.rb

@@ -2,7 +2,6 @@
 require_relative "../config/environment"
 
 require "rails/test_help"
-require "minitest/unit"
 require "mocha/minitest"
 require "webmock/minitest"
 require "turbo/broadcastable/test_helper"