rspec users - Feb 2011 - custom matchers for request specs

Hi all, I''m trying to create a custom matcher that will visit a given
path and check it''s authenticated.
Here''s what I have so far (using rspec-rails and capybara):

matcher :require_authentication do
  match do |path|
    visit path
    #page.current_path.should == sign_in_path
    page.current_path.should == ''/sign_in''
  end
end

The above version works, but when using the commented out line I get:

  NameError:
       undefined local variable or method `sign_in_path'' for
#<RSpec::Matchers::Matcher:0xbbd68ec>

sign_in_path is one of the routes in my application and works fine
inside a describe/it block.
I don''t understand why the matcher recognises visit() but not
sign_in_path.

any ideas?

On 4 Feb 2011, at 09:30, Alan B wrote:
> Hi all, I''m trying to create a custom matcher that will visit a
given
> path and check it''s authenticated.
> Here''s what I have so far (using rspec-rails and capybara):
> 
> matcher :require_authentication do
>  match do |path|
>    visit path
>    #page.current_path.should == sign_in_path
>    page.current_path.should == ''/sign_in''
>  end
> end
> 
> The above version works, but when using the commented out line I get:
> 
>  NameError:
>       undefined local variable or method `sign_in_path'' for
> #<RSpec::Matchers::Matcher:0xbbd68ec>
> 
> sign_in_path is one of the routes in my application and works fine
> inside a describe/it block.
> I don''t understand why the matcher recognises visit() but not
> sign_in_path.
I''m surprised either of them do. This DSL is just a factory method for
a matcher class. Unless that matcher class includes Capybara and the Rails
routing methods module (can''t remember the name off-hand) you
won''t have access to either of these methods in the matcher. Look at
the non-DSL way to create a matcher and this will make more sense.

Also, you need to return true / false from #match, rather than using an
assertion.

cheers,
Matt

matt at mattwynne.net
07974 430184

On Feb 8, 2011, at 4:14 AM, Matt Wynne wrote:
> 
> On 4 Feb 2011, at 09:30, Alan B wrote:
> 
>> Hi all, I''m trying to create a custom matcher that will visit
a given
>> path and check it''s authenticated.
>> Here''s what I have so far (using rspec-rails and capybara):
>> 
>> matcher :require_authentication do
>> match do |path|
>>   visit path
>>   #page.current_path.should == sign_in_path
>>   page.current_path.should == ''/sign_in''
>> end
>> end
>> 
>> The above version works, but when using the commented out line I get:
>> 
>> NameError:
>>      undefined local variable or method `sign_in_path'' for
>> #<RSpec::Matchers::Matcher:0xbbd68ec>
>> 
>> sign_in_path is one of the routes in my application and works fine
>> inside a describe/it block.
>> I don''t understand why the matcher recognises visit() but not
>> sign_in_path.
> 
> I''m surprised either of them do.
Actually, I''m not, but that''s because I know something that
you don''t know (because I wrote it and it''s not well
documented):

<background>
A matcher created using the Matcher DSL is provided access to the example it is
running in. When it receives method_missing, it asks the example if _it_ will
respond to the message and, if so, sends it to the example.
</background>

<educated_guess guarantees="none">
If visit() is defined in the scope of the example using "def visit",
then example.respond_to?(:visit) would return true, so the matcher would send
visit() to the example.

If, however, sign_in_path() is handled with method_missing(), but respond_to?()
is not also overridden to return true for respond_to?(:sign_in_path), then the
matcher would call super from method_missing, raising the NameError.

You can test this theory out by putting the following in the same example before
the matcher:

self.should respond_to(:visit)
self.should respond_to(:sign_in_path)

If my guess is correct, the former will pass, but the latter will fail. If they
both pass, then I''m not sure about the explanation.
</educated_guess>

HTH,
David
> This DSL is just a factory method for a matcher class. Unless that matcher
class includes Capybara and the Rails routing methods module (can''t
remember the name off-hand) you won''t have access to either of these
methods in the matcher. Look at the non-DSL way to create a matcher and this
will make more sense.
> 
> Also, you need to return true / false from #match, rather than using an
assertion.
> 
> cheers,
> Matt
> 
> matt at mattwynne.net
> 07974 430184
> 
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
Cheers,
David