Feature: Safe stubbing Most Ruby test double libraries let you stub methods that don't exist. Bogus is different in this respect: not only does it not allow stubbing methods that don't exist, it also ensures that the number of arguments you pass to those methods matches the method definition. The stubbing syntax is: stub(object).method_name(arg1, arg2, ...) { return_value } Background: Given a file named "foo.rb" with: """ruby class Library def checkout(book) end end """ Scenario: Stubbing methods that exist on real object Then spec file with following content should pass: """ruby describe Library do it "does something" do library = Library.new stub(library).checkout("some book") { :checked_out } library.checkout("some book").should == :checked_out end end """ Scenario: Stubbing methods that do not exist on real object Then spec file with following content should fail: """ruby describe Library do it "does something" do library = Library.new stub(library).buy("some book") { :bought } end end """ Scenario: Stubbing methods with wrong number of arguments Then spec file with following content should fail: """ruby describe Library do it "does something" do library = Library.new stub(library).checkout("some book", "another book") { :bought } end end """ Scenario: Stubs allow the methods to be called Then spec file with following content should pass: """ruby describe Library do it "does something" do library = Library.new stub(library).checkout("some book") { :bought } end end """ Scenario: Stubbing methods multiple times Then spec file with following content should fail: """ruby describe Library do it "stubbing with too many arguments" do library = Library.new stub(library).checkout("some book") { :bought } stub(library).checkout("book", "and one argument too many") { :whatever } end end """