Shoulda, RSpec, shoulda-matchers and models validations unit testing

rubyonrails-talk
1

I was trying out RSpec framework in a project and got stopped doing the unit test of a model. In particular, doing the test for the associations and the ActiveRecord validations.

I started writing the validations but my tests didn’t look DRY at all. Before refactoring the tests checked out and look for other people solutions.

I found out shoulda-matchers and Shoulda (which is I didn’t get it wrong is another testing framework). Actually I found another one, remarkable, but it look it doesn’t work with Rails 3.

Does anyone have any advice, comments, suggestion on this matter?

Right now I continue on using RSpec and shoulda-matchers. The last one mainly for testing the validations and associations of the models.

Any advice and/or help will be appreciated.

Thanks in advance.

2

You can start reading at section 6.2, and see how the Rails 3 Tutorial tests validations:

http://ruby.railstutorial.org/chapters/modeling-and-viewing-users-one#sec:user_model

3

Already got something like that. The main difference, is that I’m using factories.

The problem with my test, which almost follow those examples, is that I’m repeating myself each time I want to validate the same (uniqueness, length, etc).

One option is to create methods for each type of validation and that way the test will be DRY. Instead of that I was looking if there is a gem that provide me with those (keep them updated, etc).

At that point is when I found shoulda-matchers.

Otherwise this is an example of how the test looks

class User < ActiveRecord::Base

…

validates :first_name,

:presence => true,

:length => { :maximum => 32 }

validates :last_name,

:presence => true,

:length => { :maximum => 32 }

…

end

According to the examples your tests for those fields should been:

describe User do

before(:each) do

@attr = { :first_name => “Foo”, :last_name => “Bar” }

end

…

it “should require a first name” do

no_email_user = User.new(@attr.merge(:first_name => “”))

no_email_user.should_not be_valid

end

it “should require a last name” do

no_email_user = User.new(@attr.merge(:last_name => “”))

no_email_user.should_not be_valid

end

it “should reject first names that are too long” do

long_first_name = “a” * 33

long_first_name_user = User.new(@attr.merge(:first_name => long_first_name))

long_first_name_user.should_not be_valid

end

it “should reject last names that are too long” do

long_last_name = “a” * 33

long_last_name_user = User.new(@attr.merge(:last_name => long_last_name))

long_last_name_user.should_not be_valid

end

end