Rspec Quick Reference

I’ve been working to rewrite the test suite for one of the apps I’ve made from Minitest/Fixtures to Rspec/Factory Girl. My favorite thing about Minitest is that it’s simple to understand since it’s just Ruby, but I wanted to explore what Rspec has to offer. I’ve seen alot of Rspec in the open source projects I’ve looked into and in many of the tutorials I follow. Even though the syntax is easy to understand, using it to code was harder than I thought. I started a quick reference sheet from cheat sheats I found on the internet and the documentation for the gems. They don’t give a full explanation on what they do, but I found that the syntax is expressive enough that being able to see an example is enough to use it.

Structure

describe <class> do
  it "description of what happens" do 
    <setup code>
    <exercise code>
    <expectation code>
    <cleanup code>
  end
end

Setup code

before { <setup code> }
let( <variable> ) { <object instantiate> }

## Test doubles
book = double("book")
book = instance_double("book")
allow(book).to receive(:title).and_return("The Rspec Book")
allow_any_instance_of(Widget).to receive(:name).and_return("Wibble")
spy("invitation")
instance_spy("invitation")
class_spy("invitation")
object_spy("invitation")

Exercise code

## Model Tests from shoulda-matchers gem documentation

it { should <should-matchers code> }

allow_value('http://foo.com', 'http://bar.com/baz').for(:website_url)
validate_confirmation_of(:email)
validate_length_of(:password).is_at_least(10).on(:create)
validate_numericality_of(:age).only_integer
validate_presence_of(:password)
belong_to(:organization)
accept_nested_attributes_for(:mirrors).allow_destroy(true)
have_many(:friends)
have_one(:partner)
have_and_belong_to_many(:awards)

## Controller Tests

get :new

Article.should_receive(:new).with(title: 'The New Article Title').and_return(article)
post :create, message: { title: 'The New Article Title' }

article.should_receive(:save)
post :create

article.stub(:save)
post :create
response.should redirect_to(action: 'index')
flash[:notice].should eq('The article was saved successfully.')

## Feature Tests with Capybara

visit book_path
fill_in 'Email', :with => 'user@example.com'
click_on "Submit"
click_link('Link Text')
choose('A Radio Button')
check('A Checkbox')
uncheck('A Checkbox')
find_field('First Name').value
find_link('Hello').visible?
find_button('Send').click

Expectation code

expect(<expectation code>).to      eq(<value>)
expect(<expectation code>).not_to  eq(<value>)

## Paired with spy

expect(invitation).to have_received(:accept).with(mailer)

# Values that can be used 

be_true
be_false
be_nil
match /regex/
start_with 
end_with
match_array [array]
be_a_kind_of <class name>
be_an_instance_of <class name>
have(<number>).things
have_at_least(<number>).things
have_at_most(<number>).things
raise_error <optional error>

## Controller specific

assigns[:article].should be_a_new Article
response.should render_template :new

Thoughtbot articles on testing

I’ve been reading about testing philosophies and watching tutorials on TDD. I’ve been going through a lot of the blog posts on the thoughtbot because I started learning about Rspec in general from their Upcase trails and using many of their tools. These are a few of the articles I’ve read that helped me get a grip on the way people test and the terms they use.

Commands I’ve learned

git log --grep searches the commit messages
git log -S searches the code in the repo and can take Regex
tar xvf archive_name.tar extracting from a tar file
unzip test.zip extracting from a zip file

Ray's Blog