FlexMock is a flexible mocking library for use in unit testing and behavior specification in Ruby. Release 0.8.5 is a minor release with a few bug fixes.
Fixed warning about a void context.
hsh() argument matcher now reports its matching constraints in error messages.
FlexMock is a flexible framework for creating mock object for testing. When running unit tests, it is often desirable to use isolate the objects being tested from the "real world" by having them interact with simplified test objects. Sometimes these test objects simply return values when called, other times they verify that certain methods were called with particular arguments in a particular order.
FlexMock makes creating these test objects easy.
Easy integration with both Test::Unit and RSpec. Mocks created with the flexmock method are automatically verified at the end of the test or example.
A fluent interface that allows mock behavior to be specified very easily.
A "record mode" where an existing implementation can record its interaction with a mock for later validation against a new implementation.
Easy mocking of individual methods in existing, non-mock objects.
Easy mocking of chains of method calls.
The ability to cause classes to instantiate test instances (instead of real instances) for the duration of a test.
Suppose you had a Dog object that wagged a tail when it was happy. Something like this:
class Dog def initialize(a_tail) @tail = a_tail end def happy @tail.wag end end
To test the
Dog class without a real
(perhaps because real
Tail objects activate servos in some
robotic equipment), you can do something like this:
require 'test/unit' require 'flexmock/test_unit'
class TestDog < Test::Unit::TestCase def test_dog_wags_tail_when_happy tail = flexmock("tail") tail.should_receive(:wag).once dog = Dog.new(tail) dog.happy end end
FlexMock will automatically verify that
the mocked tail object received the message
wag exactly one
time. If it doesn't, the test will not pass.
See the FlexMock documentation at flexmock.rubyforge.org for details on specifying arguments and return values on mocked methods, as well as a simple technique for mocking tail objects when the Dog class creates the tail objects directly.
You can make sure you have the latest version with a quick RubyGems command:
gem install flexmock (you may need root/admin privileges)
Otherwise, you can get it from the more traditional places:
You will find documentation at: flexmock.rubyforge.org.
-- Jim Weirich