Re: [rspec] rspec2 throws 'undefined method' for model class method (.self)

[David Chelimsky]

On Wed, Dec 5, 2012 at 3:23 PM, netzfisch <tj2...@gmail.com> wrote:
> I have model (event.rb) method, that retrieves a list of all recurrence
> dates for the named period
>
> def self.dates_between(start_date, end_date)
> dates = (start_date..end_date).step(7).to_a
> end
>
> than I specify the following in event_spec.rb
>
> before(:each) do
> @event = FactoryGirl.create(:event)
> end
> subject { @event }

Side note: recommend using this instead:

subject(:event) { FactoryGirl.create(:event) }

>
> ... other working tests ...
>
> describe '#dates_between' do
> context 'finds recurrences dates of a event' do
> start_date = "2012-12-01 18:25:25"
> end_date = "2012-12-15 18:25:25"
> output_dates = ["2012-12-01 18:25:25", "2012-12-08 18:25:25",
> "2012-12-15 18:25:25"]
>
> it 'should call Event with method dates_between' do
> @event.should_receive(:dates_between).with(start_date, end_date)
> @event.dates_between(start_date, end_date)
> end

This ^^ will pass regardless of whether the method is defined in the
right place because the should_receive statement defines the
dates_between method if it's not there. In other words, this example
is not actually testing anything besides how rspec-mocks works.

>
> it 'should find and return the RIGHT recurrences dates' do
> @event.dates_between(start_date, end_date).should
> eq(output_dates)

This is probably the one that's failing because you're defining a
class method but you're calling an instance method.

> end
> end
> end
>
> and get this failure:
>
> 1) Event#dates_between finds recurrences dates of a event should find
> and return the RIGHT recurrences dates
> Failure/Error: @event.dates_between(start_date, end_date).should
> eq(output_dates)
> NoMethodError:
> undefined method `dates_between' for #<Event:0xb99e9f8>
> # ./spec/models/event_spec.rb:52:in `block (4 levels) in <top
> (required)>'
>
> when I change in the model from a class method to an instance method
> (removing "self.") the console just prints out "wild data":
>
>> 22:93:55", "2012-12-01 22:93:62", "2012-12-01 22:93:69", "2012-12-01
>> 22:93:76", "2012-12-01 22:93:83", "2012-12-01 22:93:90", "2012-12-01
>> 22:93:97", "2012-12-01 22:94:04", "2012-12-01 22:94:11", "2012-12-01
>> 22:94:18", "2012-12-01 22:94:25", "2012-12-01 22:94:32", ...

What is wild about that data? Looks like what you're defining in the
example. What data are you expecting here?

[netzfisch]

Am Mittwoch, 5. Dezember 2012 22:32:41 UTC+1 schrieb dchel...@gmail.com:

On Wed, Dec 5, 2012 at 3:23 PM, netzfisch <tj2...@gmail.com> wrote:
> I have model (event.rb) method, that retrieves a list of all recurrence
> dates for the named period
>
>       def self.dates_between(start_date, end_date)
>          dates = (start_date..end_date).step(7).to_a
>       end
>
> than I specify the following in event_spec.rb
>
>       before(:each) do
>         @event = FactoryGirl.create(:event)
>       end
>       subject { @event }

Side note: recommend using this instead:

  subject(:event) { FactoryGirl.create(:event) }

 

thanks for the feedback: ist that statement also executed before every describe/it statement, because there are further test: see https://github.com/netzfisch/teamorga/blob/master/spec/models/event_spec.rb 

>
>       ... other working tests ...
>
>       describe '#dates_between' do
>         context 'finds recurrences dates of a event' do
>           start_date = "2012-12-01 18:25:25"
>           end_date = "2012-12-15 18:25:25"
>           output_dates = ["2012-12-01 18:25:25", "2012-12-08 18:25:25",
> "2012-12-15 18:25:25"]
>
>           it 'should call Event with method dates_between' do
>             @event.should_receive(:dates_between).with(start_date, end_date)
>             @event.dates_between(start_date, end_date)
>           end

This ^^ will pass regardless of whether the method is defined in the
right place because the should_receive statement defines the
dates_between method if it's not there. In other words, this example
is not actually testing anything besides how rspec-mocks works.

ok, the intention was, to test that the class method get called (I read that this the main difference between 'stub' and 'should_receive'  with the two attributes? How should I change that? 

 

>
>           it 'should find and return the RIGHT recurrences dates' do
>             @event.dates_between(start_date, end_date).should
> eq(output_dates)

This is probably the one that's failing because you're defining a
class method but you're calling an instance method.

right, but how do I ask for a class-method. Beside that I could change the behaviour in the modell and controller, but that is not really intended: https://github.com/netzfisch/teamorga/blob/master/app/models/event.rb
https://github.com/netzfisch/teamorga/blob/master/app/controllers/events_controller.rb

>           end
>         end
>       end
>
> and get this failure:
>
>     1) Event#dates_between finds recurrences dates of a event should find
> and return the RIGHT recurrences dates
>      Failure/Error: @event.dates_between(start_date, end_date).should
> eq(output_dates)
>      NoMethodError:
>        undefined method `dates_between' for #<Event:0xb99e9f8>
>      # ./spec/models/event_spec.rb:52:in `block (4 levels) in <top
> (required)>'
>
> when I change in the model from a class method to an instance method
> (removing "self.") the console just prints out "wild data":
>
>> 22:93:55", "2012-12-01 22:93:62", "2012-12-01 22:93:69", "2012-12-01
>> 22:93:76", "2012-12-01 22:93:83", "2012-12-01 22:93:90", "2012-12-01
>> 22:93:97", "2012-12-01 22:94:04", "2012-12-01 22:94:11", "2012-12-01
>> 22:94:18", "2012-12-01 22:94:25", "2012-12-01 22:94:32", ...

What is wild about that data? Looks like what you're defining in the
example. What data are you expecting here?

ok, you are right, I expect

  ["2012-12-01 18:25:25", "2012-12-08 18:25:25", "2012-12-15 18:25:25"] 

but probably should expext without time, which screws my console by iterating through every second - minute - hour for the three expected days

  ["2012-12-01", "2012-12-08", "2012-12-15"] 

although it works in production? Probably I should define in the model a date-format without time - not sure there is one? Anyway, it is not really intended:

https://github.com/netzfisch/teamorga/blob/master/db/schema.rb

[Myron Marston]

On Wednesday, December 5, 2012 1:23:36 PM UTC-8, netzfisch wrote:

I have model (event.rb) method, that retrieves a list of all recurrence dates for the named period

      def self.dates_between(start_date, end_date)

         dates = (start_date..end_date).step(7).to_a

      end

than I specify the following in event_spec.rb

      before(:each) do

        @event = FactoryGirl.create(:event)

      end    

      subject { @event }

      ... other working tests ...

    

      describe '#dates_between' do

        context 'finds recurrences dates of a event' do

          start_date = "2012-12-01 18:25:25"

          end_date = "2012-12-15 18:25:25"

          output_dates = ["2012-12-01 18:25:25", "2012-12-08 18:25:25", "2012-12-15 18:25:25"]

    

          it 'should call Event with method dates_between' do

            @event.should_receive(:dates_between).with(start_date, end_date)

            @event.dates_between(start_date, end_date)

          end

    

          it 'should find and return the RIGHT recurrences dates' do

            @event.dates_between(start_date, end_date).should eq(output_dates)

          end

        end

      end

and get this failure:

    1) Event#dates_between finds recurrences dates of a event should find and return the RIGHT recurrences dates

     Failure/Error: @event.dates_between(start_date, end_date).should eq(output_dates)

     NoMethodError:

       undefined method `dates_between' for #<Event:0xb99e9f8>

     # ./spec/models/event_spec.rb:52:in `block (4 levels) in <top (required)>'

when I change in the model from a class method to an instance method (removing "self.") the console just prints out "wild data":

> 22:93:55", "2012-12-01 22:93:62", "2012-12-01 22:93:69", "2012-12-01

> 22:93:76", "2012-12-01 22:93:83", "2012-12-01 22:93:90", "2012-12-01

> 22:93:97", "2012-12-01 22:94:04", "2012-12-01 22:94:11", "2012-12-01

> 22:94:18", "2012-12-01 22:94:25", "2012-12-01 22:94:32", ...

any ideas?

If you want to test a class method, then your test needs to send the message *to the class object*, not to an instance of that class:

class Event

  def self.dates_between

  end

end

Event.dates_between # calls the defined method

Event.new.dates_between # raises a NoMethodError because Event instances don't respond to #dates_between

HTH,

Myron 

[netzfisch]

Thanks, both answers helped me getting the specs green!

Last questions, 

• does the first "it-statement" make sense now? 
  
• Will the "subject-statement" also executed before(:each) describe-/it-statement?
  

Now I do:

class Event

  def self.dates_between(start_date, end_date)
    dates = (start_date..end_date).step(7).to_a
  end

end

describe Event do

  subject(:event) { FactoryGirl.create(:event) }

  describe '#dates_between' do

    context 'finds recurrences dates of a event' do

 

      start_date = "2012-12-01"

      end_date = "2012-12-15"

      output_dates = ["2012-12-01", "2012-12-08", "2012-12-15"]

      it 'should call dates_between with two arguments' do

        event.should_receive(:dates_between).with(start_date, end_date).and_return(output_dates)

        event.dates_between(start_date, end_date).should eq(output_dates)

      end

      it 'should find and return the RIGHT recurrences dates' do

        Event.dates_between(start_date, end_date).should eq(output_dates)

      end

    end

  end

end