Module | RSpec::Core::Subject::ClassMethods |
In: |
lib/rspec/core/subject.rb
|
Creates a nested example group named by the submitted attribute, and then generates an example using the submitted block.
# This ... describe Array do its(:size) { should == 0 } end # ... generates the same runtime structure as this: describe Array do describe "size" do it "should == 0" do subject.size.should == 0 end end end
The attribute can be a Symbol or a String. Given a String with dots, the result is as though you concatenated that String onto the subject in an expression.
describe Person do subject do Person.new.tap do |person| person.phone_numbers << "555-1212" end end its("phone_numbers.first") { should == "555-1212" } end
When the subject is a Hash, you can refer to the Hash keys by specifying a Symbol or String in an array.
describe "a configuration Hash" do subject do { :max_users => 3, 'admin' => :all_permissions } end its([:max_users]) { should == 3 } its(['admin']) { should == :all_permissions } # You can still access to its regular methods this way: its(:keys) { should include(:max_users) } its(:count) { should == 2 } end
Defines an explicit subject for an example group which can then be the implicit receiver (through delegation) of calls to should.
describe CheckingAccount, "with $50" do subject { CheckingAccount.new(:amount => 50, :currency => :USD) } it { should have_a_balance_of(50, :USD) } it { should_not be_overdrawn } end
See +ExampleMethods#should+ for more information about this approach.