How can I stub a method within a module:
module SomeModule
def method_one
# do stuff
something = method_two(some_arg)
# so more stuff
end
def method_two(arg)
# do stuff
end
end
I can test method_two in isolation fine.
I would like to test method_one in isolation too by stubbing the return value of method_two:
shared_examples_for SomeModule do
it 'does something exciting' do
# neither of the below work
# SomeModule.should_receive(:method_two).and_return('MANUAL')
# SomeModule.stub(:method_two).and_return('MANUAL')
# expect(described_class.new.method_one).to eq(some_value)
end
end
describe SomeController do
include_examples SomeModule
end
The specs in SomeModule that are included in SomeController fail because method_two throws an exception (it tries to do a db lookup that has not been seeded).
How can I stub method_two when it is called within method_one?
allow_any_instance_of(M).to receive(:foo).and_return(:bar)
Is there a way to stub a method of an included module with Rspec?
This approach works for me
shared_examples_for SomeModule do
let(:instance) { described_class.new }
it 'does something exciting' do
instance.should_receive(:method_two).and_return('MANUAL')
expect(instance.method_one).to eq(some_value)
end
end
describe SomeController do
include_examples SomeModule
end
Related
I've been trying to stub a private module method for the whole day now but with not progress.
Here is a snippet of my application controller class
class ApplicationController < ActionController::Base
include Cesid::Application
end
Cesid > Application.rb
module Cesid
module Application
extend ActiveSupport::Concern
included do
before_action :track_marketing_suite_cesid, only: [:new]
end
private
def track_marketing_suite_cesid
return unless id_token_available?
## #cesid_auth = Auth.new(#id_token)
#cesid_auth = Auth.new(id_token)
return unless #cesid_auth.present? && #cesid_auth.valid?
#cesid_admin = Admin.where(email: #cesid_auth.email).first_or_initialize
end
def id_token_available?
## #id_token.present?
id_token.present?
end
def id_token
#id_token ||= id_token_param
end
def id_token_param
cookies[:id_token]
end
end
end
Now, I'm trying to create a simple unit test for the method
id_token_available?
And I am just trying to set the id_token_param to a random value.
I've tried using this code as stated Is there a way to stub a method of an included module with Rspec?
allow_any_instance_of(Cesid).to receive(:id_token_param).and_return('hello')
but I just get this error
NoMethodError:
undefined method `allow_any_instance_of' for #<RSpec::ExampleGroups::CesidApplication::CesidAuthorizations::GetCesidApplication:0x00007fa3d200c1c0> Did you mean? allow_mass_assignment_of
Rspec file
require 'rails_helper'
describe Cesid::Application, :type => :controller do
describe 'cesid application' do
before do
allow_any_instance_of(ApplicationController).to receive(:id_token_param).and_return('hello')
end
it 'returns true if the id_token is present' do
expect(Cesid::Application.send('id_token_available?')).to eql(true)
end
end
end
Rspec version
3.5.4
This is honestly starting to drive me crazy
I see three issues:
You call allow_any_instance_of in a context in which it is not defined. allow_any_instance_of can be used in before blocks. I need to see your RSpec code to be more specific.
Actually your code is called on the ApplicationController, not on the module, therefore you need to change your stub to
allow_any_instance_of(ApplicationController).to receive(:id_token_param).and_return('hello')
Currently id_token_param will not be called at all, because id_token_available? checks the instance variable and not the return value of the id_token method that calls the id_token_param. Just change the id_token_available? to:
def id_token_available?
id_token.present?
end
There's a much better way of going about this test. The type: :controller metadata on your spec gives you an anonymous controller instance to work with.
Here's an example of how you could write this to actually test that the before_action from your module is used:
describe Cesid::Application, type: :controller do
controller(ApplicationController) do
def new
render plain: 'Hello'
end
end
describe 'cesid before_action' do
before(:each) do
routes.draw { get 'new' => 'anonymous#new' }
cookies[:id_token] = id_token
allow(Auth).to receive(:new).with(id_token)
.and_return(instance_double(Auth, valid?: false))
get :new
end
context 'when id token is available' do
let(:id_token) { 'hello' }
it 'sets #cesid_auth' do
expect(assigns(:cesid_auth)).to be_present
end
end
context 'when id token is unavailable' do
let(:id_token) { '' }
it 'does not set #cesid_auth' do
expect(assigns(:cesid_auth)).to be_nil
end
end
end
end
I have FooConcern and BarService as follows:
module FooConcern
extend ActiveSupport::Concern
def notify_slack(message)
# send message to slack
end
end
class BarService
include FooConcern
def run
# do some stuff
message = 'blah, blah'
notify_slack(message)
end
end
How can I write to mock notify_slack so I don't actually call slack API when I run Rspec test for BarService#run ?
RSpec.describe BarService do
describe 'run' do
subject { described_class.new.run }
it do
# some tests on things other than notifying slack
end
end
end
You can use allow to mock that method.
RSpec.describe BarService do
describe 'run' do
subject { described_class.new }
it do
allow(subject).to receive(:notify_slack).and_return(true)
# some tests on things other than notifying slack
subject.run
end
end
end
Im writing a test for this service.
def run
sort_offers(product).each do |product_code|
......
offer.update(poduct_params)
Importer::Partner.get_details(product_code).new
end
end
It's calling a service which in some cases will override the values that were saved when running offer.update(product_prams). How would I go about skipping the service call within my test?
Here is the example of my test
context 'is valid' do
.... .....
before do
Importer::ProductCodes(product).run
end
it ......
end
I would stub Importer::Partner.get_details to return a double that responds to new:
context 'is valid' do
before do
allow(Importer::Partner).to receive(:get_details).and_return(double(new: nil))
end
# it ...
end
Depending on your needs you might want to add an expectation that the mock was called with the correct parameters and that new was actually called on the mock too:
context 'is valid' do
let(:mock) { double(new: nil) }
before do
allow(Importer::Partner).to receive(:get_details).and_return(double(new: nil))
end
it "calls the service" do
an_instance.run
expect(Importer::Partner).to have_received(:get_details).with(
foo: 'bar' # the arguments you would expect
)
expect(mock).to have_received(:new)
end
end
RSpec has a very capable stubbing and mocking library built in (rspec mocks).
require 'spec_helper'
module Importer
class Partner
def self.get_details(product_code)
"original return value"
end
end
end
class FooService
def self.run
Importer::Partner.get_details('bar')
end
end
RSpec.describe FooService do
let(:partner_double) { class_double("Importer::Partner") }
before do
stub_const("Importer::Partner", partner_double)
allow(partner_double).to receive(:get_details).and_return 'our mocked value'
end
it "creates a double for the dependency" do
expect(FooService.run).to eq 'our mocked value'
end
end
class_double creates a double for the class and you can set the return values by using .expect and .allow and the mocking interface. This is quite useful since you can stub out the new or intialize methods to return a double or spy.
stub_constant will reset the constant to its previous value when the spec is done.
That said you can avoid the use of stub_constant by using constructor injection in your services:
class PhotoImportService
attr_accessor :client, :username
def initialize(username, api_client: nil)
#username = username
#client = api_client || APIClient.new(ENV.fetch('API_KEY'))
end
def run
client.get_photos(username)
end
end
I have the following:
class PaymentController < ActionController::API
include ObjectActions
def error_notification(message)
puts "An error has occurred: #{message}"
end
end
module ObjectActions
extend ActiveSupport::Concern
def process
if valid?
# process payment
else
error_notification("Payment is not valid")
end
end
end
Now, I'm trying to mock/stub the "external" error_notification method inside ObjectActions module/concern.
RSpec.describe ObjectActions, type: :concern do
include ObjectActions
before do
allow(described_class).to receive(:valid?).and_return(false)
# I KNOW THIS IS NOT RIGHT, HOW CAN I PROPERLY MOCK IT?
allow(described_class).to receive(:error_notification).and_return("Blah blah")
end
context '#process' do
it { expect { process }.to eq("Blah blah") }
end
end
Short answer would be
allow(self).to receive(:error_notification).and_return("Blah blah")
Why?
You're including the module, you want to test in the current test
RSpec.describe ObjectActions, type: :concern do
include ObjectActions
So this is what you're supposed to mock. But it's a bit better way to do it, which I described not long ago in this answer: https://stackoverflow.com/a/48914463/299774
I have the following class, that I am trying to write a spec for:
module IntegrationError
class Error < StandardError; end
class BadRequest < IntegrationError::Error; end
class LogicProblem < IntegrationError::Error; end
def raise_logic_error!(message)
raise IntegrationError::LogicProblem, message
rescue => e
Rails.logger.error e.message
e.backtrace.each do |line|
Rails.logger.error line if line.include?('integrations')
end
end
def raise_bad_request!(message)
raise IntegrationError::BadRequest, message
end
def log_bad_request!(message)
Rails.logger.info message
end
end
with spec
RSpec.describe 'IntegrationError', type: :integration do
let!(:klass) { Class.new { include IntegrationError } }
describe '#log_bad_request!' do
it 'logs it' do
expect(klass.new.log_bad_request!('TESTME')).to be_truthy
end
end
describe '#raise_bad_request!' do
it 'raises it' do
binding.pry
expect(klass.new.raise_bad_request!('TESTME')).to raise_error
end
end
end
the raise_bad_request test returns the error instead of true. Anyone have thoughts on how to write this better to it passes?
I'm using Rails 4 and Rspec 3.4.
If I recall correctly, I believe you need to pass the expectation a block when your raising, like this:
describe '#raise_bad_request!' do
it 'raises it' do
binding.pry
expect{klass.new.raise_bad_request!('TESTME')}.to raise_error
end
end
See docs here
For the raise_error matcher you need to pass a block to expect instead of a value:
expect { klass.raise_bad_request!('TESTME') }.to raise_error
That should do it!