RoR and RSpec: How to access controller instance variables without defining accessors?

Question

I'm writing a rspec tests for my controller and i cannot find solution following problem. For one of the edge case tests I need to verify the value of one instance variable. How can i access it without having to define the accessor? By default the usual:

controller.variable.should == '3.15'

doesn't work.

Defining

attr_reader :variable

just to make the tests pass would be silly and i'm sure that there is a more inteligent way.

Ben Hughes · Accepted Answer · 2009-07-16 14:20:36Z

44

controller.instance_variable_get(:var)

if you find yourself doing this, you might want to rethink your approach to information hiding so that you are testing essential behavior rather than incidental implementation details. Your tests should ensure that the "thing" functions as it should without being too tightly bound to the particular implementation.

EDIT: Isn't assigns(:var) the rails testing magic for doing the same thing with controllers?

edited Jul 16, 2009 at 14:20

answered Jul 16, 2009 at 14:08

Ben Hughes

14.2k1 gold badge43 silver badges34 bronze badges

Sign up to request clarification or add additional context in comments.

6 Comments

Jakub Troszok Over a year ago

Yeah probably you're right - i should test the results of the action instead of the implementation details. Thanks anyway.

Ben Hughes Over a year ago

to be fair, for controllers, instance variables are things that should be tested. I answered this question before coffee.

Tass Over a year ago

The question wasn't really relevant to exactly what I was doing, just needed to check for the existence of a controller's instance variable. @BenHughes, your answer (and subsequent answer) helped much. Thanks.

MattiSG Over a year ago

Use assigns (it's a free method, not controller.assigns), as instance_variable_get may have more restrictions than assigns. For example: 'event' is not allowed as an instance variable name, but assigns detects @event without any problem.

ecoologic Over a year ago

@BenHughes, thanks, it's something trivial to work out, but I would specify controller.instance_variable_get(:@var) and assigns(:var)

|

Collectives™ on Stack Overflow

RoR and RSpec: How to access controller instance variables without defining accessors?

1 Answer 1

6 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

6 Comments

Your Answer

Sign up or log in

Post as a guest

Related