模型未在Rails应用程序的RSpec测试中加载

Question

I've created a really simple Rails app that demonstrates my question.

It's a clean Rails 4.2 app with one model that looks like this:

# charigfy.rb

module Chargify
  class Webhook
    def self.process
      puts "Hello world"
    end
  end
end

The file is basically re-opening the Chargify module in the chargify gem and the re-opening the Webhook class in order to add a class method, process .

I've added the chargify_api_ares gem and then added a simple model spec, that looks like this:

require_relative '../test_helper'

describe Chargify::Webhook do
  context "testing" do
    it "should work" do
      Chargify::Webhook.process
    end
  end
end

When I run the spec using bundle exec rspec test/models I get this output:

Failures:

  1) Chargify::Webhook testing should work
     Failure/Error: Chargify::Webhook.process
     NoMethodError:
       undefined method `process' for Chargify::Webhook:Class
     # ./test/models/chargify_spec.rb:6:in `block (3 levels) in <top (required)>'

Finished in 0.00121 seconds (files took 3.3 seconds to load)
1 example, 1 failure

Failed examples:

rspec ./test/models/chargify_spec.rb:5 # Chargify::Webhook testing should work

Now I can make this work by either changing the model so that it doesn't re-open the module and is namespaced differently, or I can explicitly require 'chargify' in the spec, but I feel like there's a better solution.

Presumably it's not working because in describe Chargify::Webhook do it's loading the class from the gem and not from the model, seeing as it finds the appropriate class in the gem's files before the model.

What's the best or most Rails-y way of making this work?

Answer 1

IMHO the best way to patch/extend Ruby classes that are loaded by Rails is to move your code out of app/models (or lib ) and into an initializer. Rails executes initializers as one of the final steps when booting up, so you are less likely to run into load order issues.

The main drawback of initializers is that you must restart the server to apply changes, which is less convenient than reloading in development.

See the docs for more about Rails initialization and configuration .