Back to Repositories

Testing RailsAdmin Engine Configuration Reloading in rails_admin

This test suite validates the RailsAdmin Engine’s configuration reloading functionality in development mode. It specifically focuses on how the admin interface handles class unloading and configuration updates during Rails’ code reloading process.

Test Coverage Overview

The test coverage focuses on the dynamic reconfiguration of RailsAdmin fields during development.

Verifies field configuration persistence across reloads
Tests class unloading behavior
Ensures proper config reinitialization
Validates development mode specific features

Implementation Analysis

The testing approach simulates Rails’ code reloading mechanism in a controlled environment. It utilizes RSpec’s context and let blocks to maintain test isolation, while leveraging Rails’ executor and ActiveSupport::Reloader to replicate real-world development scenarios.

Uses before/after hooks for environment setup
Implements dynamic configuration changes
Simulates Rails application reloading

Technical Details

RSpec testing framework
Rails application executor
ActiveSupport::Reloader
RailsAdmin configuration DSL
Development mode cache settings

Best Practices Demonstrated

The test suite exemplifies proper testing practices for Rails engine development.

Proper test environment isolation
Clean setup and teardown
Explicit state management
Clear expectations and assertions
Realistic scenario simulation

railsadminteam/rails_admin

spec/rails_admin/engine_spec.rb

            
# frozen_string_literal: true

require 'spec_helper'

RSpec.describe RailsAdmin::Engine do
  context 'on class unload' do
    let(:fields) { RailsAdmin.config(Player).edit.fields }
    before do
      Rails.application.config.cache_classes = false
      RailsAdmin.config(Player) do
        field :name
        field :number
      end
    end
    after { Rails.application.config.cache_classes = true }

    it 'triggers RailsAdmin config to be reloaded' do
      # this simulates rails code reloading
      RailsAdmin::Engine.initializers.find do |i|
        i.name == 'RailsAdmin reload config in development'
      end.block.call(Rails.application)
      Rails.application.executor.wrap do
        ActiveSupport::Reloader.new.tap(&:class_unload!).complete!
      end

      RailsAdmin.config(Player) do
        field :number
      end
      expect(fields.map(&:name)).to match_array %i[number]
    end
  end
end