Rspec not changing count on create - ruby-on-rails

Question

I am trying to resolve an issue with my rspec test to create an object but the count doesn't seem to change whatever i try. I am sure i am missing something very basic here.
Here is my rspec:
before do
login_account_admin(user)
#group = Factory(:group, :code => "GR_111", :description => "description for GR_111")
Group.stub!(:find).and_return(#group)
end
describe "#create" do
it "should create a new group object" do
group_params = {:code => "NEW_GROUP", :description => "description for NEW_GROUP"}
expect {
post :create, :service_id => service, :cdb_group => group_params, :button => "save", :format => "js"
}.to change(Group, :count).by(1)
end
it "should not create a new group object with invalid code format" do
group_params = {:code => "invalid", :description => "description for invalid code name group"}
expect {
post :create, :service_id => service, :cdb_group => group_params, :button => "save", :format => "js"
}.to_not change(Group, :count)
end
end
"code" parameter can only contain uppercase letters A to Z, 0-9 and _
Here is the controller method definition for #create
def create
#group = Group.new(params[:cdb_group])
respond_to do |format|
if params[:button] == "cancel"
format.js { render "hide_new"}
elsif #group.save
format.js {
render 'show_new_group'
}
format.html { redirect_to(some_path(#service), :notice => 'Group was successfully created.') }
format.xml { head :ok }
end
end
end
Here is the Group model:
class Group < ActiveRecord::Base
validates_uniqueness_of :code
validates_presence_of :code, :description
validates_format_of :code, :without => /[^A-Z0-9_]/ , :message => 'can only contain uppercase letters A to Z, 0-9 and _'
end
Whenever i try to run the rspec test I get the following errors:-
1) GroupsController User As Account Admin goes to #create should create a new group object
Failure/Error: expect {
count should have been changed by 1, but was changed by 0
# ./spec/controllers/groups_controller_spec.rb:51
2) GroupsController User As Account Admin goes to #create should not create a new group object with invalid code format
Failure/Error: expect {
count should not have changed, but did change from 2 to 1
# ./spec/controllers/groups_controller_spec.rb:58
Any help in this regard would be highly appreciated?

Answer 1

Whenever our tests give us unexpected trouble, it's important to take a step back and re-evaluate our approach. Usually, this is an indication of some design problem, either with the code we're testing or with tests themselves.
While it sounds like using a truncation strategy has fixed this particular problem (see more on that below), i would suggest that there is more to learn from the situation.
Consider the two examples from your spec above. The only difference between them comes down to whether the code parameter is valid or not. I would argue that these examples are really testing the Group model, not the controller.
Now, if we're confident in our model test coverage, then we can take a different approach to the controller spec. From the controller's perspective, the model is a collaborator and in general, we always want to avoid indirectly testing collaborators. In this case, we can use a mock to simulate the behavior of the Group model and only test the controller behavior in isolation.
Something like this (please note the code below is incomplete and untested):
# spec/controllers/groups_controller_spec.rb
describe "#create" do
before do
# use a Test Double instead of a real model
#new_group = double(Group)
#params = { :cdb_group => 'stub_cdb_group_param', :service_id => service }
# using should_receive ensures the controller calls new correctly
Group.should_receive(:new).with(#params[:cdb_group]).and_return(#new_group)
end
context "when cancelled responding to js" do
it "renders hide_new" do
post :create, #params.merge({:button => "cancel", :format => "js"})
expect(response).to render_template('hide_new')
end
end
context "with valid params" do
before do
#new_group.should_receive(:save).and_return(true)
end
context "responding to json" # ...
context "responding to html" # ...
context "responding to xml" #...
end
context "with invalid params" do
before do
#new_group.should_receive(:save).and_return(false)
end
# ...
end
end
While the above doesn't specifically address the problem with record counts you were having, i suspect the problem may go away once you isolate your test targets correctly.
If you choose to stick with database truncation, consider using it selectively as described here.
I hope at least some of that helps :).

Answer 2

After fiddling with my spec_helper.rb file. It turns out that i have to change my database cleaning strategy to truncation. Here is my spec_helper file, for reference (https://gist.github.com/aliibrahim/7152042)
I changed this line in my code and disable use of transactional_fixtures
config.use_transactional_fixtures = false
and my database cleaning strategy is now:
config.before(:suite) do
DatabaseCleaner.strategy = :truncation
DatabaseCleaner.clean_with(:truncation)
end
This gives a clear database before the start/end of every scenario. Hope this helps anyone!

Answer 3

You should test...
1) Group.create(group_params).should be_true after group_params = ...
If this fails, the problem probably related to model or test environment.
2) response.status.should == 302 after post ...
If this fails, the problem probably related to session (authentication / authorization).
3) assigns(:group).should be_valid after post ...
If this fails, the problem probably related to controller.