ExampleGroups and Examples
Rather than expressing examples in classes, RSpec uses a custom DSLL (DSL light) to describe groups of examples.
A ExampleGroup is the equivalent of a fixture in xUnit-speak. It is a metaphor for the context in which you will run your executable example - a set of known objects in a known starting state. We begin be describing
describe Account do before do @account = Account.new end it "should have a balance of $0" do @account.balance.should == Money.new(0, :dollars) end end
We use the before block to set up the Example (given), and then the #it method to hold the example code that expresses the event (when) and the expected outcome (then).
A primary goal of RSpec is to keep the examples clear. We therefore prefer less indirection than you might see in xUnit examples and in well factored, DRY production code. We feel that duplication is OK if removing it makes it harder to understand an example without having to look elsewhere to understand its context.
That said, RSpec does support some level of encapsulating common code in helper methods that can exist within a context or within an included module.
Setup and Teardown
You can use before and after within a Example. Both methods take an optional scope argument so you can run the block before :each example or before :all examples
describe "..." do before :all do ... end before :each do ... end it "should do something" do ... end it "should do something else" do ... end after :each do ... end after :all do ... end end
The before :each block will run before each of the examples, once for each example. Likewise, the after :each block will run after each of the examples.
It is also possible to specify a before :all and after :all block that will run only once for each behaviour, respectively before the first before :each and after the last after :each. The use of these is generally discouraged, because it introduces dependencies between the examples. Still, it might prove useful for very expensive operations if you know what you are doing.
Local helper methods
You can include local helper methods by simply expressing them within a context:
describe "..." do it "..." do helper_method end def helper_method ... end end
Included helper methods
You can include helper methods in multiple contexts by expressing them within a module, and then including that module in your context:
module AccountExampleHelperMethods def helper_method ... end end describe "A new account" do include AccountExampleHelperMethods before do @account = Account.new end it "should have a balance of $0" do helper_method @account.balance.should eql(Money.new(0, :dollars)) end end
Shared <a href="/rspec/Spec/Example">Example</a> Groups
You can define a shared <a href="/rspec/Spec/Example">Example</a> Group, that may be used on other groups
share_examples_for "All Editions" do it "all editions behaviour" ... end describe SmallEdition do it_should_behave_like "All Editions" it "should do small edition stuff" do ... end end
You can also assign the shared group to a module and include that
share_as :AllEditions do it "should do all editions stuff" ... end describe SmallEdition do it_should_behave_like AllEditions it "should do small edition stuff" do ... end end
And, for those of you who prefer to use something more like Ruby, you can just include the module directly
describe SmallEdition do include AllEditions it "should do small edition stuff" do ... end end
BehaviourRunner = ExampleGroupRunner
lib/spec/runner/class_and_arguments_parser.rb lib/spec/runner/example_group_runner.rb lib/spec/runner/formatter/base_formatter.rb lib/spec/runner/formatter/base_text_formatter.rb lib/spec/runner/formatter/failing_example_groups_formatter.rb lib/spec/runner/formatter/failing_examples_formatter.rb lib/spec/runner/formatter/html_formatter.rb lib/spec/runner/formatter/nested_text_formatter.rb lib/spec/runner/formatter/profile_formatter.rb lib/spec/runner/formatter/progress_bar_formatter.rb lib/spec/runner/formatter/snippet_extractor.rb lib/spec/runner/formatter/specdoc_formatter.rb lib/spec/runner/formatter/story/html_formatter.rb lib/spec/runner/formatter/story/plain_text_formatter.rb lib/spec/runner/formatter/text_mate_formatter.rb lib/spec/runner/heckle_runner_unsupported.rb lib/spec/runner/reporter.rb lib/spec/runner/backtrace_tweaker.rb lib/spec/runner/command_line.rb lib/spec/runner/drb_command_line.rb lib/spec/runner/heckle_runner.rb lib/spec/runner/option_parser.rb lib/spec/runner/options.rb lib/spec/runner/spec_parser.rb lib/spec/runner.rb