Stubbing method in ActionDispatch::IntegrationTest

Question

I'm doing some stripe integration tests and I would like to stub/mock a few endpoints. I'm attempting to do it like this:

Stripe::Charge.stubs(:retrieve).returns({:balance_transaction => 40})

but I'm getting the following:

NoMethodError: undefined method `stubs' for Stripe::Charge:Class

What's the correct syntax for stubbing this? Rails 4, Ruby 2.

Edit: Here is my full test method. Essentially my payment_succeeded webhook hits stripe to retrieve a charge and it's associated balance transaction in order to log the transaction fee. I'm using stripe_mock to mock the webhook events, but I'd rather stub out the rest of them using standard stubbing techniques. Note that even when I change it to 'stub' it throws the same error above (with stub substituted for stubs).

require 'test_helper'
require 'stripe_mock'

class WebhooksTest < ActionDispatch::IntegrationTest
  # called before every single test
  def setup
    StripeMock.start
  end

  # called after every single test
  def teardown
    StripeMock.stop
  end

  test 'invoice.payment_succeeded' do
    Stripe::Charge.stubs(:retrieve).returns({:balance_transaction => 40})
    event = StripeMock.mock_webhook_event('invoice.payment_succeeded', { :customer => "stripe_customer1", :id => "abc123" })
    post '/stripe-events', id: event.id
    assert_equal "200", response.code
    assert_equal 1, StripeInvoicePayment.count
    assert_equal 'abc123', event.data.object.id
  end
end

Answer 1

The only thing that looks incorrect to me here is .stubs when it should be .stub.

Answer 2

Since you aren't using RSpec, I would recommend installing the mocha gem to get a full selection of mocking and stubbing tools. Here's a quickstart:

# Gemfile
gem "mocha", :group => :test

# test/test_helper.rb
require "mocha/mini_test"

Now you can stub like this:

Stripe::Charge.stubs(:retrieve => {:balance_transaction => 40})

Or, if you'd like to verify the method was actually called, you could set up an expectation instead:

Stripe::Charge.expects(:retrieve)
  .with(:id => "abc123")
  .returns({:balance_transaction => 40})