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

Robot Framework

https://robotframework.org/

SimpleTest

https://github.com/simpletest/simpletest
Programming language

Python

PHP

Category

Acceptance Testing

Unit Testing, Web Testing

General info

Robot is a Python framework used for acceptance/functional testing

Robot is an automated test framework which has a simple plain text syntax and can be extended easily with Python or Java libraries. It can run on the .net-based IronPython and on Jython which is Java based.

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
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

No

No

Client-side
Allows testing code execution on the client, such as a web browser

Yes

Robot has a rich library and can also be easily integrated with Selenium for browser automation to test front-end components

Yes

With SimpleTest common but fiddly PHP tasks, such as logging into a site, can be tested easily
Server-side
Allows testing the bahovior of a server-side code

Yes

Robot can be used for back-end tests as well

Yes

Server-side behaviour can be tested by writing simple unit tests to test functionality and behaviour of single components.
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

There is no inbuilt way to work with fixtures in Robot however it can integrate with unittest and use fixtures that way

Yes

It can import fixtures using a mixin like 'given()' method
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.

By integrating with unittest

Yes

It allows grouping of fixtures
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

Robot has a library called the Robot Framework Faker library. It contains 147 keywords used for generating random test data

Yes

Simpletest has support for generators
Licence
Licence type governing the use and redistribution of the software

Apache License 2.0

GNU Lesser General Public License v2.1

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

Robot can access Python's mock library for mocking

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.
Grouping
Allows organizing tests in groups

Yes

One can create a test suite with Robot

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
Other
Other useful information about the testing framework