All I'm trying to do is spec how a one line helper method for a view should behave, but I'm not sure what kind of mock object, (if any) I should be creating if I'm working in Rails.
Here's the code for events_helper.rb:
module EventsHelper
def filter_check_button_path
params[:filter].blank? ? '/images/buttons/bt_search_for_events.gif' : '/images/buttons/bt_refine_this_search.gif'
end
end
And here's my spec code, in events_helper_spec.rb:
require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
describe EventsHelper do
#Delete this example and add some real ones or delete this file
it "should be included in the object returned by #helper" do
included_modules = (class << helper; self; end).send :included_modules
included_modules.should include(EventsHelper)
end
it "should return the 'refine image search' button if a search has been run" do
# mock up params hash
params = {}
params[:filter] = true
# create an instance of the class that should include EventsHelper by default, as the first test has verified (I think)
#event = Event.new
# call method to check output
#event.filter_check_button_path.should be('/images/buttons/bt_search_for_events.gif')
end
end
When I've looked through the docs here - http://rspec.info/rails/writing/views.html, I'm mystified as to where the 'template' object comes from.
I've also tried looking here, which I thought would point me in the right direction, but alas, no dice. http://jakescruggs.blogspot.com/2007/03/mockingstubbing-partials-and-helper.html
What am I doing wrong here?
Thanks,
Chris
You are not doing anything in that spec, just setting a stub, so it will pass, but hasn't tested anything.
require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
describe EventsHelper do
it "should return the 'refine image search' button if a search has been run" do
# mock up params hash
params = {:filter => true}
helper.stub!(:params).and_return(params)
helper.filter_check_button_path.should eql('/images/buttons/bt_search_for_events.gif')
end
end
I'm running my test without spec_helper (Ruby 1.9)
require_relative '../../app/helpers/users_helper'
describe 'UsersHelper' do
include UsersHelper
...
end
Ah,
I asked this question on the rspec mailing list, and one kind soul (thanks Scott!) explained to me that there's a handy helper object for this, that you should use instead, like so:
Rails has its own helper function
params = {:filter => true}
helper.stub!(:params).and_return(params)
I've now updated the code like so:
require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
describe EventsHelper do
#Delete this example and add some real ones or delete this file
it "should be included in the object returned by #helper" do
included_modules = (class << helper; self; end).send :included_modules
included_modules.should include(EventsHelper)
end
it "should return the 'refine image search' button if a search has been run" do
# mock up params hash
params = {}
params[:filter] = true
helper.stub!(:filter_check_button_path).and_return('/images/buttons/bt_search_for_events.gif')
end
end
And it's working. Huzzah!
Related
I'm starting to attempt to incorporate more testing into my code, but I've hit a wall.
My model looks something like this
class Image < ActiveRecord:Base
before_create :do_something_general
before_update :do_something_on_update, :do_something_general
belongs_to :captureable, polymorphic: true
mount_uploader :image, SomeUploader
...
end
My rspec looks something like
describe SomeModel do
before :each do
#image = FactoryGirl.create(:image)
end
...
describe "moving image" do
context "change the parent of the image" do
it "moves" do
new_parent = FactoryGirl.create(:parent)
current_file_path = #image.image.file.path
#image.captureable = new_parent
#image.save!
#image.image.file.path.should_not == current_file_path
end
end
end
end
When I first create an Image, it will get stored in a file tree structure that depends on its parents. When a parent changes, the Image should be moved, and this is done with the before_update callback :do_something_on_update. My test should verify that when the Image has had its parent changed, it is located in a new location.
The problem is, when #image.save.should be_valid an except is returned because :do_something_general is run before :do_something_on_update (the order is important). It seems that the rspec thinks I'm creating a new object (using debugger I've checked that the object id doesn't change when modifying it), and thus runs before_create instead of before_update.
Edit: it seems that before_update is working, but only on callback methods that are in the class, but not in the module. In this case, :do_something_on_update is located in an included module.
End Edit
When I try this in the console in development mode, it works as expected.
Other things to note: I'm using Carrierwave for uploading (the image column is a carrierwave uploader) and when the :image factory is called, it also creates several parents and grandparent objects. Using Rspec 2.10, Rails 3.2.8, Ruby 1.9.3
Looking forward to your responses.
Thanks.
I would expect image.save.should be_valid to fail, because it's going to invoke image.save, which returns true or false, then it's going to invoke #valid? on that boolean result, which should likely fail.
You might consider writing your test like so:
describe SomeModel do
let(:image) { FactoryGirl.create(:image) }
context "when changing the parent of the image" do
let(:parent_change) { lambda {
image.captureable = FactoryGirl.create(:parent)
image.save!
} }
it "updates the image's path" do
expect parent_change.to change { image.image.file.path }
end
end
end
This ensures that you only have one assertion in the test (that the file path is changing), and that if the save fails, it will instead raise an exception.
I'm writing the following test:
let!(:city_areas) { FactoryGirl.create_list(:city_area, 30) }
before {
#city_areas = mock_model(CityArea)
CityArea.should_receive(:where).and_return(city_areas)
}
it 'should assign the proper value to city areas variable' do
get :get_edit_and_update_vars
assigns(:city_areas).should eq(city_areas.order("name ASC"))
end
to test the following method:
def get_edit_and_update_vars
#city_areas = CityArea.where("city_id = '#{#bar.city_id}'").order("name ASC").all
end
However, it fails out, saying that there's no method 'city_id' for nil:NilClass, leading me to believe it's still attempting to use the instance variable #bar.
How do I properly stub out this where statement to prevent this?
Why are you doing #city_areas = mock_model(CityArea) and then you never use #city_areas again?
I would test it this way:
inside the model CityArea create a named scope for this: where("city_id = '#{#bar.city_id}'").order("name ASC")
then in your controller spec you do
describe 'GET get_edit_and_update_vars' do
before(:each) do
#areas = mock('areas')
end
it 'gets the areas' do
CityArea.should_receive(:your_scope).once.and_return(#areas)
get :get_edit_and_update_vars
end
it 'assign the proper value to city areas variable' do
CityArea.stub!(:your_scope => #areas)
get :get_edit_and_update_vars
assigns(:city_areas).should eq(ordered)
end
end
and you should also create a spec for that new scope on the model spec
just a tip, you shouldn't use should_receive(...) inside the before block, use stub! inside before and use should_receive when you want to test that method is called
also, you shouldn't need to use factorygirl when testing controllers, you should always mock the models, the model can be tested on the model spec
How I can setup controller/response objects from scratch to ran render_to_string?
I developed an application which generate a PDF file.
I used erb based template to generate TeX file, then process it to convert to PDF.
It's working fine, but I now start thinking it is better to generate the report in background. Thus, I created a queuing system using delayed_job and it's working well.
Now, when combine two of them, I realized that renderer implemented as part of controller.
What I want to do is run render_to_string to generate the PDF. It looks like I need to setup controller and response object from scratch.
I found a question (How do I call controller/view methods from the console in Rails?) relate to this, but setting up a response object by calling post seems awkward.
How I can setup controller and response object to achieve this?
Here's one way to do it (generating the PDF via wicked_pdf):
Controller:
class FoosController < ApplicationController
def queue_pdf_generation
#foo = Foo.find(params[:id])
Delayed::Job.enqueue GeneratePdfJob.new(#foo.id)
end
end
Delayed Job:
class GeneratePdfJob < Struct.new(:foo_id)
def perform
# get the Foo object when the job is run
foo = Foo.find(foo_id)
# create an instance of ActionView, so we can use render method outside of a controller
av = ActionView::Base.new()
av.view_paths = ActionController::Base.view_paths
pdf_html = av.render :template => "foos/pdf.html.erb", :layout => nil, :locals => {:foo => foo}
# use wicked_pdf gem to create PDF from the foo HTML
foo_pdf = WickedPdf.new.pdf_from_string(pdf_html, :page_size => 'Letter')
# save PDF to disk
pdf_path = Rails.root.join('tmp', "#{foo.id}.pdf")
File.open(pdf_path, 'wb') do |file|
file << foo_pdf
end
end
A couple notes:
The "perform" method doesn't take a parameter; inheriting from a
struct lets us pass a parameter to the GeneratePdfJob object, and it
sets up a local variable called "foo_id" that we can use in the
"perform" method.
Your view needs to reference the local variable
"foo" rather than an instance variable "#foo".
I want to use an ActiveModel callback to be called after an object has been voted on, the issue is that the gem I'm using (voteable_mongo) to make the model votable doesnt provide like a vote model or callback in my app, so how can I create a callback for it?
set_callback(:vote, :before) do |object|
object.do_something
end
Obviously that vote action I made up, but the gem I'm using has this method, how would you properly extend this method to trigger a callback?
Taking the plugin example as source here's what you could do:
class Post
include Mongoid::Document
include Mongo::Voteable
extend ActiveModel::Callbacks
define_model_callbacks :vote
# set points for each vote
voteable self, :up => +1, :down => -1
def vote(options, value = nil)
_run_vote_callbacks do
super( options, value )
end
end
end
I did not run this code so I am not sure if this is going to work correctly or not, but in the worst case you could alias the vote method using alias_method_chain or just copy and paste the source to inside the _run_vote_callbacks block (really, really ugly, but it's a solution anyway).
EDIT
This could also be done using alias_method_chain, if the code above does not work:
class Post
include Mongoid::Document
include Mongo::Voteable
extend ActiveModel::Callbacks
define_model_callbacks :vote
# set points for each vote
voteable self, :up => +1, :down => -1
alias_method_chain :vote, :callback
def vote_with_callback(options, value = nil)
_run_vote_callbacks do
vote_without_callbacks( options, value )
end
end
end
I am looking to pass a value to a custom validation. I have done the following as a test:
validate :print_out, :parameter1 => 'Hello'
With this:
def print_out (input="blank")
puts input
end
When creating an object or saving an object, the output is 'blank.' However, if called directly:
object.print_out "Test"
Test is instead outputted. The question is, why is my parameter not passing properly?
Inside the 'config\initializers\' directory, you can create your own validations. As an example, let's create a validation 'validates_obj_length.' Not a very useful validation, but an acceptable example:
Create the file 'obj_length_validator.rb' within the 'config\intializers\' directory.
ActiveRecord::Base.class_eval do
def self.validates_obj_length(*attr_names)
options = attr_names.extract_options!
validates_each(attr_names, options) do |record, attribute, value|
record.errors[attribute] << "Error: Length must be " + options[:length].to_s unless value.length == options[:length]
end
end
end
Once you have this, you can use the very clean:
validates_obj_length :content, :length => 5
Basically, we reopen ActiveRecord::Base class and implement a new sub-validation. We use the splat (*) operator to accept an array of arguments. We then extract out the hash of options into our 'options' variable. Finally we implement our validation(s). This allows the validation to be used with any model anytime and stay DRY!
You could try
validate do |object_name|
object_name.print_out "Hello"
end
Instead of your validate :print_out, :parameter1 => 'Hello'.