Add ActionText support

Attachment support is not included here, since it requires webpack-built javascripts.
Closes #3144

app/assets/javascripts/rails_admin/ra.widgets.coffee

@@ -349,3 +349,11 @@ $(document).on 'rails_admin.dom_ready', (e, content) ->
           goFroalaWysiwygs(array)
       else
         goFroalaWysiwygs(array)
+
+    # action_text
+
+    content.find('trix-editor').each ->
+      if !window.Trix
+        options = $(this).data('options')
+        $('head').append('<link href="' + options['csspath'] + '" rel="stylesheet" media="all" type="text\/css">')
+        $.getScript options['jspath']

app/views/rails_admin/main/_form_action_text.html.haml

@@ -0,0 +1,7 @@
+:ruby
+  js_data = {
+    csspath: field.css_location,
+    jspath: field.js_location
+  }
+
+= form.rich_text_area field.method_name, field.html_attributes.reverse_merge(data: { options: js_data.to_json })

lib/rails_admin/config/fields.rb

@@ -85,4 +85,5 @@ def self.register_factory(&block)
 require 'rails_admin/config/fields/factories/refile'
 require 'rails_admin/config/fields/factories/active_storage'
 require 'rails_admin/config/fields/factories/shrine'
+require 'rails_admin/config/fields/factories/action_text'
 require 'rails_admin/config/fields/factories/association'

lib/rails_admin/config/fields/factories/action_text.rb

@@ -0,0 +1,12 @@
+require 'rails_admin/config/fields'
+require 'rails_admin/config/fields/types'
+
+RailsAdmin::Config::Fields.register_factory do |parent, properties, fields|
+  if defined?(::ActionText) && properties.try(:association?) && (match = /\Arich_text_(.+)\Z/.match properties.name) && properties.klass.to_s == 'ActionText::RichText'
+    field = RailsAdmin::Config::Fields::Types.load(:action_text).new(parent, match[1], properties)
+    fields << field
+    true
+  else
+    false
+  end
+end

lib/rails_admin/config/fields/types/action_text.rb

@@ -0,0 +1,31 @@
+require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/text'
+
+module RailsAdmin
+  module Config
+    module Fields
+      module Types
+        class ActionText < RailsAdmin::Config::Fields::Types::Text
+          # Register field type for the type loader
+          RailsAdmin::Config::Fields::Types.register(self)
+
+          register_instance_option :version do
+            '1.1.1'
+          end
+
+          register_instance_option :css_location do
+            "https://cdnjs.cloudflare.com/ajax/libs/trix/#{version}/trix.css"
+          end
+
+          register_instance_option :js_location do
+            "https://cdnjs.cloudflare.com/ajax/libs/trix/#{version}/trix.js"
+          end
+
+          register_instance_option :partial do
+            :form_action_text
+          end
+        end
+      end
+    end
+  end
+end

lib/rails_admin/config/fields/types/all.rb

@@ -1,3 +1,4 @@
+require 'rails_admin/config/fields/types/action_text'
 require 'rails_admin/config/fields/types/active_record_enum'
 require 'rails_admin/config/fields/types/active_storage'
 require 'rails_admin/config/fields/types/belongs_to_association'

spec/dummy_app/app/active_record/field_test.rb

@@ -52,6 +52,8 @@ def carrierwave_assets=(files)
   include ShrineUploader.attachment(:shrine_asset)
   include ShrineVersioningUploader.attachment(:shrine_versioning_asset)
 
+  has_rich_text :action_text_field if defined?(ActionText)
+
   enum string_enum_field: {S: 's', M: 'm', L: 'l'}
   enum integer_enum_field: [:small, :medium, :large]
 end

spec/dummy_app/config/application.rb

@@ -11,6 +11,7 @@
 end
 
 require 'active_storage/engine' if Rails.version >= '5.2.0' && CI_ORM == :active_record
+require 'action_text/engine' if Rails.version >= '6.0.0' && CI_ORM == :active_record
 
 # Require the gems listed in Gemfile, including any gems
 # you've limited to :test, :development, or :production.

spec/dummy_app/db/migrate/20190531065324_create_action_text_tables.action_text.rb

@@ -0,0 +1,13 @@
+class CreateActionTextTables < ActiveRecord::Migration[5.0]
+  def change
+    create_table :action_text_rich_texts do |t|
+      t.string     :name, null: false
+      t.text       :body, size: :long
+      t.references :record, null: false, polymorphic: true, index: false
+
+      t.timestamps
+
+      t.index [:record_type, :record_id, :name], name: "index_action_text_rich_texts_uniqueness", unique: true
+    end
+  end
+end

spec/integration/config/edit/rails_admin_config_edit_spec.rb

@@ -1005,6 +1005,18 @@ class HelpTest < Tableless
     end
   end
 
+  describe 'ActionText Support' do
+    it 'works without error', js: true do
+      RailsAdmin.config FieldTest do
+        edit do
+          field :action_text_field
+        end
+      end
+      expect { visit new_path(model_name: 'field_test') }.not_to raise_error
+      is_expected.to have_selector('trix-toolbar')
+    end
+  end if defined?(ActionText)
+
   describe 'Paperclip Support' do
     it 'shows a file upload field' do
       RailsAdmin.config User do

spec/rails_admin/config/fields/types/action_text_spec.rb

@@ -0,0 +1,5 @@
+require 'spec_helper'
+
+describe RailsAdmin::Config::Fields::Types::ActionText do
+  it_behaves_like 'a generic field type', :action_text_field
+end if defined?(ActionText)