Understanding Rspec Stubs and Controller Tests - ruby-on-rails

My first time I'm using a stub and I have a controller that runs a method when the page is called. If that method returns empty I want a redirect back to the home page. Thus my controller looks like this
def jobs
if scrap_cl().empty?
redirect_to home_path
flash[:error] = "Nothing found this month!"
end
end
For my test, I want to test the redirect when that method returns empty. So far I have this
context "jobs redirects to homepage when nothing returned from crawlers" do
before do
PagesController.stub(:scrap_cl).and_return("")
get :jobs
end
it { should respond_with(:success) }
it { should render_template(:home) }
it { should set_the_flash.to("Nothing found this month!")}
end
When I run rpsec I get the two errors, one on rendering the template and the other on flash. Thus, it's sending me to to the jobs page. What am I doing wrong with the stub and test?

Your stub there is going to stub out a class method called scrap_cl, which will never be called. You want the instance method. You can get to this easily with RSpec's any_instance:
PagesController.any_instance.stub(:scrap_cl).and_return("")
This will cause all instances of PagesController to stub that method, which is what you actually want here.

Related

Rspec passes class method but fails instance method

I'm trying to write a failing Rspec test. The actual test is associated with much longer code, but I narrowed down the problem to the class method it's testing.
Here's the test in Rspec:
context "For '.CASH.' as a stock" do
let!(:cash) { FactoryGirl.create(:stock, symbol: '.CASH.', name: 'cash', status: 'Available') }
describe "When update_stock runs on it" do
it "should still have an 'Available' status" do
# status should be 'Error' and test should fail
Stock.change_to_error
expect(cash.status).to eq('Available')
end
end
end
This is testing a model class method in Stock.rb:
def self.change_to_error
self.all.each do |stock|
stock.status = "Error"
stock.save
end
end
For some reason, this passes. However, if I changed it to use an instance method, it will fail like it should:
If stock_spec.rb changed to instance method:
context "For '.CASH.' as a stock" do
let!(:cash) { FactoryGirl.create(:stock, symbol: '.CASH.', name: 'cash', status: 'Available') }
describe "When update_stock runs on it" do
it "should still have an 'Available' status" do
# status should be 'Error' and test should fail
cash.change_to_error
expect(cash.status).to eq('Available')
end
end
end
And if stock.rb class method turned into an instance method:
def change_to_error
self.status = 'Error'
self.save
end
This would pass. Unfortunately, I have to use a class method instead of an instance method because I want to update all stocks in the DB. "Change_to_error" methods are just there to figure out the problem. Does anyone know why it passes as a class method when it should fail? But it fails correctly when it's using an instance method?
Effectively, what is happening is that the class method does not change the status attribute of 'cash', but the instance method does. I don't know why that is happening.
FYI, I'm using rspec-rails
Solution: Need to put 'cash.reload' after 'Stock.change_to_error' and before the expect line.
When using let! the object is created before the test. Updating the underlying data outside the object causes the instance to be outdated. Calling reload on it forces ActiveRecord to refresh it from the database.
When you use let, RSpec does not call the block until the first time you reference the attribute, in this case, cash. So in your first example, you're running change_to_error on no records at all and then checking the status on cash, a record that gets created on the line with expect. In your second example, the cash object is created, then changed to an error. I'd recommend tailing your log to confirm this (tail -f log/test.log)
If you change to let!, RSpec will create the object before every example is run. Another alternative is to reference cash in your example before calling change_to_error on all records that are created.

Having trouble with Rspec expect(double).to receive(:message)

Having been inspired by Sandi Metz's approach to writing tests (http://www.confreaks.com/videos/2452-railsconf2013-the-magic-tricks-of-testing), I am trying to refactor a test for a Rails controller to assert that it is sending a command message properly.
Here are the relevant parts of the Application:
class DealsController < ApplicationController
def index
if params[:reset]
deal_filter.reset
...
class ApplicationController
def deal_filter
...
#deal_filter ||= DealFilter.new(args)
end
...
class DealFilter
def reset
...do work...
end
...
And here is the rspec test:
describe DealsController do
it "should send 'reset' to the deal_filter" do
df = instance_double("DealFilter")
get :index, reset: "true"
expect(df).to receive(:reset)
end
end
The test results that keep coming back are:
1) DealsController GET index for any user params contain 'reset' should send 'reset' to the deal_filter
Failure/Error: expect(df).to receive(:reset)
(Double "DealFilter (instance)").reset(any args)
expected: 1 time with any arguments
received: 0 times with any arguments
I have already confirmed that the reset param is being sent through the test and that the controller is following the appropriate path, yet the test continues to fail.
Can anyone suggest a possible reason for the failure or resources for further study? I am relatively new to object oriented thinking and using mocks with Rspec. Could it be that I have misunderstood the role of doubles?
Thanks for your time!
You need to make sure your double gets used. I think the best way to do that here is to stub the deal_filter method to return the double.
I addition I would isolate the expection, so that it's the only thing in the it block. This will make it easier to add more expections without duplication the setup logic.
describe DealsController do
let(:df) { instance_double("DealFilter") }
before do
allow(controller).to receive(:deal_filter).and_return(df)
get :index, reset: "true"
end
it "should send 'reset' to the deal_filter" do
expect(df).to have_received(:reset)
end
end
I think you're expecting your instance_double to be used automatically somewhere within the index action. That's not how doubles work. You can create a double and use it for things, but your code in the controller doesn't (and shouldn't) know anything about that double and so won't ever call anything on it.
For an example of how an instance double can actually be used see this documentation.
Another issue with your expectation is that you're not setting it early enough. When you expect an object to receive a method call there needs to be something that happens after that which would invoke that method. In your example the expectation to receive :reset is the very last line of your example.
I'd recommend reading up on how other people have tested controllers with rspec as a good starting place.

Rspec controller test - how to pass arguments to a method I'm testing

I want to test this method in my controller.
def fetch_match_displayed_count(params)
match_count = 0
params.each do |param|
match_count += 1 if param[1]["result"] && param[1]["result"] != "result"
end
match_count
end
This is the test I've written so far.
describe "fetch_match_displayed_count" do
it "should assign match_count with correct number of matches" do
params = {"result_1"=>{"match_id"=>"975", "result"=>"not_match"}, "result_2"=>{"match_id"=>"976", "result"=>"match"}, "result_3"=>{"match_id"=>"977", "result"=>"not_sure"}, "result_4"=>{"match_id"=>"978", "result"=>"match"}, "result_5"=>{"match_id"=>"979", "result"=>"not_match"}, "workerId"=>"123", "hitId"=>"", "assignmentId"=>"", "controller"=>"mt_results", "action"=>"create"}
controller.should_receive(:fetch_match_displayed_count).with(params)
get :fetch_match_displayed_count, {params:params}
assigns(:match_count).should == 5
end
end
My problem seems to lie in this line get :fetch_match_displayed_count, {params:params}
The method is expecting params, but is getting nil.
I have two questions.
Should this method be in a helper and not in the controller itself (per Rails convention)?
How do I submit a get request and pass params in my test?
As a general rule, you should test the public interface of your class. For a controller, this means you test actions, not helper methods.
You should be able to make this work by setting up one or more separate test cases that call the appropriate action(s), then use a message expectation to test that the helper method is called with the right arguments -- or test that the helper method does what it is supposed to do (sets the right instance variables/redirects/etc).

Prevent controller action from direct execution by user in Rails

I have a situation where i need to prevent users from explicitly calling say /town/addBuilding. Town is my controller and addBuilding is the action that is executed.
Now, the thing is that this action should only be executed in my program's code and not by a user requesting to execute it. Moreover, this action is executed like a callback. In my application_controller, when some condition is met, the controller action is triggered and there is a redirection. In php, a simple guard like defining a guard and checking against it would be enough. Is there an equivalent thing in rails and if so, what is the best way to implement it ?
Thanx for reading and i appreciate your help :)
EDIT: I'm pasting some code to make it clearer, note that /town/addBuilding was an example, the controller names and actions below are differently named.
Now, that is the actual application controller code, it is part of a browser game that i'm coding.
def checkQuest
if TavernQuest.hasQuest(current_user)
quest = TavernQuest.getQuest(current_user)
if quest.end_time < Time.now # get quest info and check if the quest has been completed
TavernQuest.deleteQuest(current_user)
redirect_to :controller => 'tavern', :action => 'monsterAttack'
end
end
end
The tavern controller action is just the plain code that i want to execute, but only if the redirection happens inside the application controller.
It seems that you are trying to put logic into a controller which actually should belong in a model or a library.
Why do i say this: aside from the current_user and the redirect, all the code is more related to your model (where the knowledge should be) and not your controller. Your model knows when a user's quest is expired.
Example implementation:
class TavernQuest
def self.user_quest_is_expired?(user)
quest = getQuest(current_user)
if quest && quest.end_time < Time.now
TavernQuest.deleteQuest(current_user)
true
else
false
end
end
end
and in your controller you just need to write
redirect_to :controller => 'tavern', :action => 'monsterAttack' if TavernQuest.user_quest_is_expired?(current_user)
Put the addBuilding method under a line that starts with protected, as follows
protected
def addBuilding
#your code
end
Enjoy!
EDIT: In addition to this you might also wanna use the before_filter in your controllers... I'll post the exact syntax soon.
before_filter :addBuilding, :only => :method_name
method_name is the method from which :addBuilding can be accessed, no other method can access this method after adding in this line..
EDIT: Ok, so based on the info you provided, protected wont work since if we put your secret action under protected only the tavern controller will have access to it.
EDIT: Please consider using Sessions to check if the users have a valid session when they try to to execute the monsterAttack action..

Stubbing named_scope in an RSpec Controller

I haven't been able to find anything for a situation like this. I have a model which has a named scope defined thusly:
class Customer < ActiveRecord::Base
# ...
named_scope :active_customers, :conditions => { :active => true }
end
and I'm trying to stub it out in my Controller spec:
# spec/customers_controller_spec.rb
describe CustomersController do
before(:each) do
Customer.stub_chain(:active_customers).and_return(#customers = mock([Customer]))
end
it "should retrieve a list of all customers" do
get :index
response.should be_success
Customer.should_receive(:active_customers).and_return(#customers)
end
end
This is not working and is failing, saying that Customer expects active_customers but received it 0 times. In my actual controller for the Index action I have #customers = Customer.active_customers. What am I missing to get this to work? Sadly, I'm finding that it's easier to just write the code than it is to think of a test/spec and write that since I know what the spec is describing, just not how to tell RSpec what I want to do.
I think there's some confusion when it comes to stubs and message expectations. Message expectations are basically stubs, where you can set the desired canned response, but they also test for the call to be made by the code being tested. In contrast stubs are just canned responses to the method calls. But don't mix a stub with a message expectation on the same method and test or bad things will happen...
Back to your question, there are two things (or more?) that require spec'ing here:
That the CustomersController calls Customer#active_customers when you do a get on index. Doesn't really matter what Customer#active_customers returns in this spec.
That the active_customers named_scope does in fact return customers where the active field is true.
I think that you are trying to do number 1. If so, remove the whole stub and simply set the message expectation in your test:
describe CustomersController do
it "should be successful and call Customer#active_customers" do
Customer.should_receive(:active_customers)
get :index
response.should be_success
end
end
In the above spec you are not testing what it returns. That's OK since that is the intent of the spec (although your spec is too close to implementation as opposed to behavior, but that's a different topic). If you want the call to active_customers to return something in particular, go ahead and add .and_returns(#whatever) to that message expectation. The other part of the story is to test that active_customers works as expected (ie: a model spec that makes the actual call to the DB).
You should have the array around the mock if you want to test that you receive back an array of Customer records like so:
Customer.stub_chain(:active_customers).and_return(#customers = [mock(Customer)])
stub_chain has worked the best for me.
I have a controller calling
ExerciseLog.this_user(current_user).past.all
And I'm able to stub that like this
ExerciseLog.stub_chain(:this_user,:past).and_return(#exercise_logs = [mock(ExerciseLog),mock(ExerciseLog)])

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