SimpleTest vs RSpec comparison of testing frameworks
What are the differences between SimpleTest and RSpec?

	SimpleTest https://github.com/simpletest/simpletest	RSpec https://rspec.info
Programming language	PHP	Ruby
Category	Unit Testing, Web Testing	Unit Testing, Intergration Testing
General info	SimpleTest is a unit test and web test framework for PHP It has JWebUnit style functionality and support for SSL, forms, frames, proxies and basic authentication	Domain Specific Language (DSL) testing solution for Ruby code It focuses on empowering Test Driven Development (TDD). RSpec contains multiple smaller libraries, which may be independently used with other testing frameworks.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	No	Yes Yes, but it differs from more traiditional xUnit solutions. Its tests are written in a "Tests as Specification" manner. This means that the terminology used in RSpec is adjusted to a language more fitting for specification.
Client-side Allows testing code execution on the client, such as a web browser	Yes With SimpleTest common but fiddly PHP tasks, such as logging into a site, can be tested easily	Yes RSpec is used to primarily test the behaviour of applications or individual components so it can test front-end behaviour as well - you can use capybara gem with RSpec for that.
Server-side Allows testing the bahovior of a server-side code	Yes Server-side behaviour can be tested by writing simple unit tests to test functionality and behaviour of single components.	Yes You can test server-side behaviour with Rspec
Fixtures Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test	Yes It can import fixtures using a mixin like 'given()' method	Yes RSpec does contain fixture methods
Group fixtures Allows defining a fixed, specific states of data for a group of tests (group-fixtures). This ensures specific environment for a given group of tests.	Yes It allows grouping of fixtures	Yes Group fixture methods are supported
Generators Supports data generators for tests. Data generators generate input data for test. The test is then run for each input data produced in this way.	Yes Simpletest has support for generators	Yes RSpec contains generators for example intergration_'test_name' which will save a spec inside the spec/requests folder
Licence Licence type governing the use and redistribution of the software	GNU Lesser General Public License v2.1	MIT License
Mocks Mocks are objects that simulate the behavior of real objects. Using mocks allows testing some part of the code in isolation (with other parts mocked when needed)	Yes It allows for one to build Mock objects.To create a mock version of a class we need to include the mock object library and run the generator. This will create a clone class which we use to create new instances(objects) in our test cases.	Yes Available through rspec-mocks gem.
Grouping Allows organizing tests in groups	Yes There are several ways of grouping tests; one is to simply place multiple test cases into a single file, another is to mark any base test cases that should not be run as abstract, Simpletest gives you a couple of options	Yes Allows declaring example groups and contexts.
Other Other useful information about the testing framework