rspec users - Jul 2009 - Telling rspec that a method might be called with a OR b ... ?

Hey list,

Let''s say I have a model, and I want to setup a partial mock in it, to
set the expectation that it should receive a message with specific
arguments. I know that this is not a good design for a spec, and that
I would probably need to separate this in another example -- but let''s
say that I would like to express in the example that this partial mock
could receive this message with agument a OR b. I had a situation
where I have setup the should receive with a specific argument, but
later on in the code flow, the class received the same message (find)
with other arguments, which was breaking the spec. The null_object
pattern would not work, because afaik, it is only for messages and not
for arguments. Any way to tell rspec that a method might be called
with argument A or B (or C) ? :)

Thanks in advance,

MArcelo.

On Tue, Jul 28, 2009 at 2:28 PM, Marcelo de Moraes
Serpa<celoserpa at gmail.com> wrote:
> Hey list,
>
> Let''s say I have a model, and I want to setup a partial mock in
it, to
> set the expectation that it should receive a message with specific
> arguments. I know that this is not a good design for a spec, and that
> I would probably need to separate this in another example -- but
let''s
> say that I would like to express in the example that this partial mock
> could receive this message with agument a OR b. I had a situation
> where I have setup the should receive with a specific argument, but
> later on in the code flow, the class received the same message (find)
> with other arguments, which was breaking the spec. The null_object
> pattern would not work, because afaik, it is only for messages and not
> for arguments. Any way to tell rspec that a method might be called
> with argument A or B (or C) ? :)
There is no way to specify A or B, but you can stub both and set
expectations about the resulting behavior that tie back to the stub
values you set up. For example:

@thing = stub_model(Thing)
Thing.stub!(:new).and_return(@thing)
Thing.stub!(:create).and_return(@thing)
Thing.stub!(:create!).and_return(@thing)

If you do that in a before(:each) block, now the implementation can
use any of those methods and set expectations like
assigns[:thing].should == @thing, etc. This effectively does what you
are doing, but not in the most explicit way.

HTH,
David
>
> Thanks in advance,
>
> MArcelo.
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
>

On Tue, Jul 28, 2009 at 4:57 PM, David Chelimsky<dchelimsky at gmail.com>
wrote:
>> for arguments. Any way to tell rspec that a method might be called
>> with argument A or B (or C) ? :)
>
> There is no way to specify A or B, but you can stub both and set
> expectations about the resulting behavior that tie back to the stub
> values you set up. For example:
>
> @thing = stub_model(Thing)
> Thing.stub!(:new).and_return(@thing)
> Thing.stub!(:create).and_return(@thing)
> Thing.stub!(:create!).and_return(@thing)
>
> If you do that in a before(:each) block, now the implementation can
> use any of those methods and set expectations like
> assigns[:thing].should == @thing, etc. This effectively does what you
> are doing, but not in the most explicit way.
I think though that the OP want''s to set a message expectation with
variation on the arguments, NOT which message.

Something like

   @some_object.should_receive(:some_message).with(any_of(a, b, c))

As long as you don''t need to set different return values for different
arguments, that could be done with a new ArgumentMatcher.

-- 
Rick DeNatale

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