ruby on rails - Rspec Test validations of 'on: : update' not working (Rails4/Rspec 3) -

i have model implemented validate prevent change after initial value has been set (during object creation).

it works way:

models/deal.rb

validate :quantity_not_changeable, on: :update  def quantity_not_changeable       if quantity_changed?         errors.add(:quantity,          "change of defined qty not possible")       end     end 

this works in app: created new deal, works. try edit changing 'quantity' field, fails. try edit field (apart 'quantity'), works. working.

but rspec test test fails.

actually i know not work because there problem on: : validate.

indeed without 'on: : validate', test passes, of course can't remove 'on: :update', want user not able edit after initial creation of deal).

describe deal    let(:admin_user) { factorygirl.create(:admin_user) }    before(:each)     @attr = {       title:                              "neque porro quisquam est qui dolorem",       description:                        "lorem ipsum lorem ipsum lorem ipsum lorem ipsum lorem ipsum lorem ipsum",       quantity:  10     }   end  describe "my test"   describe "test nb of quantity can't changed after initial creation"         "fails if initial quantity changed"        deal = deal.create(@attr)       deal.update(quantity: 15)            expect(deal).to have(1).errors_on(:quantity)      end   end 

but rspec error:

failure/error: expect(deal).to have(1).errors_on(:quantity)        expected 1 errors on :quantity, got 0 

i going use below "print variable": p deal show why sure due on: :update not working in tests.

first: if place 'p deal' before updating it, let's see value of deal object:

describe "my test"   describe "test nb of quantity can't changed after initial creation"         "fails if initial quantity changed"        deal = deal.create(@attr)       p deal       deal.update(quantity: 15)            expect(deal).to have(1).errors_on(:quantity)      end   end 

i following output (we see normal: quantity indeed 10)

#<title: "neque porro quisquam est qui dolorem", description: "lorem ipsum lorem ipsum lorem ipsum lorem ipsum lo...", quantity: 10> 

second: let's move 'p deal' after attempt in test update value of 'quantity'

describe "my test"   describe "test nb of quantity can't changed after initial creation"         "fails if initial quantity changed"        deal = deal.create(@attr)       deal.update(quantity: 15)       p deal            expect(deal).to have(1).errors_on(:quantity)      end   end 

now output is:(we see contrary expect due validate on: :update in code, rspec test manage unfortunately update value of quantity):

#<title: "neque porro quisquam est qui dolorem", description: "lorem ipsum lorem ipsum lorem ipsum lorem ipsum lo...", quantity: 15> 

so don't understand why in reality, tested manually , can not update, in rspec test suite update!!!

hours understand no success...i tried find online resources , on: :update weak way things. don't know weird bug.

please help.

i guess entry isn't saved when called create method because of other validation. can try open console rails c , evaluate following:

deal = deal.create(title: 'mytitle', description: 'mydescription', quantity: 10) deal.persisted? 

then if got false in order find out errors when creating:

deal.errors.messages 

edit

this test should passes:

it "fails if initial quantity changed"    deal = deal.create(@attr)   deal.update(quantity: 26)        expect(deal.errors.messages).to eq({quantity: ["change of defined qty not possible"]}) end 

but these should not:

it "exploited test should not pass because messages hash should not empty"    deal = deal.create(@attr)   deal.update(quantity: 26)        expect(deal.errors.messages.empty?).to eq(true) end  "exploited test in other variation"    deal = deal.create(@attr)   deal.update(quantity: 26)        expect(deal.errors.messages).to eq({}) end