rspec users - Aug 2009 - question about throw_symbol

Given
   rspec 1.2.8
   ruby 1.8.6 (2008-08-11 patchlevel 287) [universal-darwin9.0]

And the following spec:

   def over_limit?(a)
     catch(:over_limit) do
       a.each do |x|
         throw(:over_limit) if x > 10
       end
     end
   end

   describe "when over limit" do
     it "should throw symbol :over_limit" do
       lambda{
         over_limit?([0, 5, 11])
       }.should throw_symbol(:over_limit)
     end
   end

One would expect this to pass, however this is the result:

   when over limit
   - should throw symbol :over_limit (FAILED - 1)

   1)
   ''when over limit should throw symbol :over_limit'' FAILED
   expected :over_limit but nothing was thrown
   ./spec/rspec_tests/rutabaga_spec.rb:125:

When the catch is removed, it works.

Can anyone reproduce this behavior?

thanks

Paul Mylchreest
paul.mylchreest at mac.com

On Tue, Aug 18, 2009 at 12:19 PM, Paul
Mylchreest<paul.mylchreest at mac.com> wrote:
> Given
> ?rspec 1.2.8
> ?ruby 1.8.6 (2008-08-11 patchlevel 287) [universal-darwin9.0]
>
> And the following spec:
>
> ?def over_limit?(a)
> ? ?catch(:over_limit) do
> ? ? ?a.each do |x|
> ? ? ? ?throw(:over_limit) if x > 10
> ? ? ?end
> ? ?end
> ?end
>
> ?describe "when over limit" do
> ? ?it "should throw symbol :over_limit" do
> ? ? ?lambda{
> ? ? ? ?over_limit?([0, 5, 11])
> ? ? ?}.should throw_symbol(:over_limit)
> ? ?end
> ?end
>
> One would expect this to pass, however this is the result:
>
> ?when over limit
> ?- should throw symbol :over_limit (FAILED - 1)
>
> ?1)
> ?''when over limit should throw symbol :over_limit'' FAILED
> ?expected :over_limit but nothing was thrown
> ?./spec/rspec_tests/rutabaga_spec.rb:125:
>
> When the catch is removed, it works.
That''s correct. The catch in over_limit() catches the throw, so it
does not bubble out of the method.
>
> Can anyone reproduce this behavior?
>
> thanks
>
> Paul Mylchreest
> paul.mylchreest at mac.com
>
>
>
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
>

Thanks David,

So, taking from your book, on page 212:

=begin
   def working_too_hard?
     catch :working_too_hard do
       weeks.each do |week|
         people.each do |person|
           throw :working_too_hard, true if person.hours_for(week) > 50
         end
       end
     end
   end

   To set an expectation that a symbol is thrown, we wrap up the code  
in a proc
   and set the expectation on the proc:

   lambda {
     team.working_too_hard?
   }.should throw_symbol(:working_too_hard)
=end

I guess that is a typo, correct?

On 2009-Aug-18, at 14:34 , David Chelimsky wrote:
> On Tue, Aug 18, 2009 at 12:19 PM, Paul
> Mylchreest<paul.mylchreest at mac.com> wrote:
>> Given
>>  rspec 1.2.8
>>  ruby 1.8.6 (2008-08-11 patchlevel 287) [universal-darwin9.0]
>>
>> And the following spec:
>>
>>  def over_limit?(a)
>>    catch(:over_limit) do
>>      a.each do |x|
>>        throw(:over_limit) if x > 10
>>      end
>>    end
>>  end
>>
>>  describe "when over limit" do
>>    it "should throw symbol :over_limit" do
>>      lambda{
>>        over_limit?([0, 5, 11])
>>      }.should throw_symbol(:over_limit)
>>    end
>>  end
>>
>> One would expect this to pass, however this is the result:
>>
>>  when over limit
>>  - should throw symbol :over_limit (FAILED - 1)
>>
>>  1)
>>  ''when over limit should throw symbol :over_limit''
FAILED
>>  expected :over_limit but nothing was thrown
>>  ./spec/rspec_tests/rutabaga_spec.rb:125:
>>
>> When the catch is removed, it works.
>
> That''s correct. The catch in over_limit() catches the throw, so it
> does not bubble out of the method.
>
>>
>> Can anyone reproduce this behavior?
>>
>> thanks
>>
>> Paul Mylchreest
>> paul.mylchreest at mac.com
>>
>>
>>
>> _______________________________________________
>> rspec-users mailing list
>> rspec-users at rubyforge.org
>> http://rubyforge.org/mailman/listinfo/rspec-users
>>
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
Paul Mylchreest
paul.mylchreest at mac.com

On 18 Aug 2009, at 20:16, Paul Mylchreest wrote:
> So, taking from your book, on page 212:
[...]
> I guess that is a typo, correct?
As an aside, I don''t understand this section of the book
("Expecting a
Throw") at all. The original version of the loop already "short  
circuits" (with return) without using throw/catch. What does "as soon
as working_too_hard == true" mean? And yes, it''s weird to be
setting a
throw_symbol expectation on a call to a method which is catching that  
throw.

Cheers,
-Tom

On Tue, Aug 18, 2009 at 2:46 PM, Tom Stuart<tom at experthuman.com>
wrote:
> On 18 Aug 2009, at 20:16, Paul Mylchreest wrote:
>>
>> So, taking from your book, on page 212:
>
> [...]
>>
>> I guess that is a typo, correct?
>
> As an aside, I don''t understand this section of the book
("Expecting a
> Throw") at all. The original version of the loop already "short
circuits"
> (with return) without using throw/catch. What does "as soon as
> working_too_hard == true" mean? And yes, it''s weird to be
setting a
> throw_symbol expectation on a call to a method which is catching that
throw.
Yes - this has been reported in the errata and has not yet been
addressed. It will be before we get to treeware :)
>
> Cheers,
> -Tom
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
>