Unable to mock BasicApi (and other) classes

[bostanigor]

For some my RSpec tests I've been mocking methods that call the API like so:

before do
  expect_any_instance_of(Hubspot::Crm::Contacts::BasicApi).to receive(:get_by_id).with(contact_id: hubspot_id)
    .and_return(OpenStruct.new({ id: hubspot_id }))
end

But I'm unable to do this as the current version is not loading the Hubspot::Crm::Contacts::BasicApi constant automatically. Well, I've added my own requires into the spec/spec_helper.rb file as follows:

require 'hubspot/helpers/get_all_helper' # I don't even know why but without this require the spec won't work
require 'hubspot/codegen/crm/contacts/api/basic_api'

Still no luck as this code would load a Hubspot::Discovery::Crm::Contacts::BasicApi constant and fill it with methods in real-time but by that point the Hubspot::Crm::Contacts::BasicApi (from the codegen folder) would be already altered by my mock which leads to an error in the BaseApiClient#define_api_methods.

@client = Hubspot::Client.new(access_token: access_token)
base_api = @client.crm.contacts.basic_api
base_api.get_by_id(contact_id: user.hubspot_id)
# cannot load such file -- hubspot/codegen/crm/contacts/models/args

What if we would require the discovery module and mock the Hubspot::Discovery::Crm::Contacts::BasicApi?

require 'hubspot/discovery/crm/contacts/api/basic_api'
expect_any_instance_of(Hubspot::Discovery::Crm::Contacts::BasicApi).to receive(:get_by_id).with(contact_id: hubspot_id)
    .and_return(OpenStruct.new({ id: hubspot_id }))
# Hubspot::Discovery::Crm::Contacts::BasicApi does not implement #get_by_id 

Well because of this requiring the module loaded it doesn't have any methods! As they are all generated real-time when a BasicApi instance is created. There is no method to stub unless there is an instance present.

I don't even know how to do this anymore

[bostanigor]

I've got an idea to stub Hubspot::Discovery::Crm::Contacts::BasicApi.new to an exact instance and maybe mock it's methods instead.

require 'hubspot/helpers/get_all_helper'
require 'hubspot/discovery/crm/contacts/api/basic_api'
Hubspot::Discovery::Crm::Contacts::BasicApi.new({access_token: '123123123123'}).get_by_id
# cannot load such file -- hubspot/codegen/crm/contacts/models/contact_id (LoadError)

As the BaseApiClient#define_api_methods check for the method in a codegen class it's reasonable it would check the Hubspot::Crm::Contacts::BasicApi#get_by_id method. And it's definition (def get_by_id(contact_id, opts = {})) shows us that it will search for a contact_id.rb in a models folder. And of course there is no such file. I don't even know how that is supposed to work.
I'll probably downgrade for now as it's a mess to test. I'm up for the dynamic reflective code (that's fun to program) but there it has too much drawbacks.
I would like to have an option to somehow preload all modules and classes in the test env and be able to stub class methods that would be there already. Thanks