Add basic CRUD tests for management pages

[wilson29thid]

Idea: Create a single ActiveAdmin controller test file which tests all pages of a list of resources. Use factories to generate attributes for creating and editing resources. These can then be supplemented by specific controller tests to test functionality beyond the basic CRUD stuff.

[wilson29thid]

I've got a basic implementation working, though it seems to break quite a few classes, e.g. ones with before-/after-save callbacks.

require "test_helper"

class Manage::ControllerTest < ActionDispatch::IntegrationTest
  namespace = ActiveAdmin.application.default_namespace
  resources = ActiveAdmin.application.namespaces[namespace].resources
    .filter { |r| r.instance_of?(ActiveAdmin::Resource) }

  resources.each do |resource|
    resource_name = resource.resource_name
    resource_title = resource_name.singular
    has_factory = FactoryBot.factories.any? { |f| f.name.to_s == resource_name.singular }
    actions = resource.defined_actions

    setup do
      @user = create(:user)
      @unit = create(:unit)
      create(:permission, abbr: "admin", unit: @unit)
      create(:assignment, user: @user, unit: @unit)
      sign_in_as @user

      @instance = create(resource_name.singular) if has_factory
    end

    if actions.include?(:index)
      test "#{resource_title} should get index" do
        get resource.route_collection_path
        assert_response :success
      end
    end

    if actions.include?(:show) && has_factory
      test "#{resource_title} should show" do
        get resource.route_instance_path(@instance)
        assert_response :success
      end
    end

    if actions.include?(:new)
      test "#{resource_title} should get new" do
        get resource.route_collection_path(:new)
        assert_response :success
      end
    end

    if actions.include?(:create) && has_factory
      test "#{resource_title} should create" do
        params = {}
        params[resource_title] = build(resource_name.singular).attributes.symbolize_keys

        assert_difference("#{resource.resource_class}.count", 1) do
          post resource.route_collection_path, params: params
        end

        assert_redirected_to resource.route_instance_path(resource.resource_class.last)
      end
    end

    if actions.include?(:edit) && has_factory
      test "#{resource_title} should get edit" do
        get resource.route_edit_instance_path(@instance)
        assert_response :success
      end
    end

    if actions.include?(:update) && has_factory
      test "#{resource_title} should update" do
        params = {}
        params[resource_title] = @instance.attributes.symbolize_keys
        instance_path = resource.route_instance_path(@instance)
        patch instance_path, params: params
        assert_redirected_to instance_path
      end
    end

    if actions.include?(:destroy) && has_factory
      test "#{resource_title} should destroy" do
        assert_difference("#{resource.resource_class}.count", -1) do
          delete resource.route_instance_path(@instance)
        end

        assert_redirected_to resource.route_collection_path
      end
    end
  end
end