stubs MailChimp api call for functional testing

Question

I'm trying to test a MailChimp subscription to an specific list:

test/functional/some_controller_test.rb

require 'test_helper'

class SomeControllerTest < ActionController::TestCase
  test "invalid signup" do
    Gibbon.stubs(:subscribe).raises(Gibbon::MailChimpError, 500)
    post :signup, {:EMAIL => "invalid_email"}
    assert_response 500
  end

  test "valid signup" do
    Gibbon.stubs(:subscribe).returns(200)
    post :signup, {:EMAIL => "[email protected]"}
    assert_response 200
  end
end

controllers/some_controller.rb

class SomeController < ApplicationController
  def signup
    begin
      gb = Gibbon::API.new
      resp = gb.lists.subscribe(
        :id => ENV["key_list"],
        :email => {:email => "#{params[:EMAIL]}"}
      )
      render :status => :ok, :json => resp
    rescue Gibbon::MailChimpError => e
      render :status => :internal_server_error, :json => {error: e, message: e.message}
    end
  end
end

But I think that I missing something here because the tests are passing but they are doing a call to the API, because as I'm using my email for testing purposes I receive the email confirmation from MailChimp each time that I run:

"rake test:functionals"

And if I try to run:

Gibbon.any_instance.stubs(:subscribe).raises(Gibbon::MailChimpError, 500)

or

Gibbon.any_instance.stubs(:subscribe).returns(200)

I get the following errors:

test_invalid_signup(SomeControllerTest):
NoMethodError: undefined method 'any_instance' for Gibbon:Module

test_valid_signup(SomeControllerTest):
NoMethodError: undefined method 'any_instance' for Gibbon:Module

EDIT I

I was able to use any_instance method doing this:

require 'test_helper'

class NewsletterControllerTest < ActionController::TestCase
  test "invalid signup" do
    gb = Gibbon::API.new
    gb.any_instance.stubs(:subscribe).raises(Gibbon::MailChimpError, 500)
    post :signup, {:EMAIL => "invalid_email"}
    assert_response 500
  end

  test "valid signup" do
    gb = Gibbon::API.new
    gb.any_instance.stubs(:subscribe).returns(200)
    post :signup, {:EMAIL => "[email protected]"}
    assert_response 200
  end
end

But still is doing a call to the API.

Answer 1

I'm used to RSpec (not TestUnit/Mocha), so I'm not all too familiar with the correct syntax here.

However, I do notice that you need to stub any_instance of Gibbon::API, so I'm guessing Gibbon::API.any_instance is what you need at least. Besides that, you'll need to stub both the lists as well as the subscribe method.

So, I'm guessing something like this should work in your valid signup test case:

lists = stub(subscribe: stub)
Gibbon::API.any_instance.stubs(:lists).returns(lists)

I don't think you'll have to return 200, since that's what the render does.