[RSpec] LEVEL 1: INTRODUCTION
Install RSpec:
Describe
Lets start writing a specification for the Tweet
class. Write a describe
block for the Tweet model without any examples inside it.
#tweet.rb class Tweet end
Answer:
#tweet_spec.rb describe Tweet do end
It
Now create a pending test called "can set status"
.
describe Tweet do it "can set status" end
Couple of ways to make test pending:
Expectation
Now let's write the example. Go ahead and instantiate a tweet
, give it the status "Nom nom nom"
, and test the status has been properly set to this value using an ==
equality matcher.
class Tweet attr_accessor :status def initialize(options={}) self.status = options[:status] end def public? self.status && self.status[0] != "@" end end
Answer:
describe Tweet do it 'can set status' do tweet = Tweet.new tweet.status = "Nom nom nom" tweet.status.should == "Nom nom nom" end end
Matchers
Using a predicate 'be' matcher, make sure that a tweet
like "Nom nom nom"
(which is not a reply because it doesn't start with an '@' sign) is public
.
describe Tweet do it 'without a leading @ symbol should be public' do tweet = Tweet.new(status: 'Nom nom nom') tweet.should be_public end end
Comparison Matchers
Finish the example below to ensure that our tweet.status.length
is less than or equal to 140 characters. Use a be
matcher in your spec.
class Tweet attr_accessor :status def initialize(options={}) self.status = options[:status] end def public? self.status && self.status[0] != "@" end def status=(status) @status = status ? status[0...140] : status end end
Answer:
describe Tweet do it 'truncates the status to 140 characters' do tweet = Tweet.new(status: 'Nom nom nom' * 100) tweet.status.length.should be <= 140 end end
Predict 'be':