Test::Unit vs Robot Framework comparison of testing frameworks
What are the differences between Test::Unit and Robot Framework?

Test::Unit

https://test-unit.github.io/

Robot Framework

https://robotframework.org/
Programming language

Ruby

Python

Category

Unit Testing, Intergration Testing

Acceptance Testing

General info

Test::Unit is a unit testing framework for Ruby

Test::Unit is an implementation of the xUnit testing framework for ruby which is used for Unit Testing. However Test::Unit has been left in the standard library to support legacy test suites therefore if you are writing new test code use Minitest instead of Test::Unit

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

Yes

test-unit is a xUnit family unit testing framework for Ruby

No

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

It could have tested some front-end components but its now legacy hence wouldn't work with the many new front-end components

Yes

Robot has a rich library and can also be easily integrated with Selenium for browser automation to test front-end components
Server-side
Allows testing the bahovior of a server-side code

Yes

Yes

Robot can be used for back-end tests as well
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

Fixture methods are available through its ClassMethods Module

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

Group fixture methods are supported

By integrating with unittest
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.

No

Yes

Robot has a library called the Robot Framework Faker library. It contains 147 keywords used for generating random test data
Licence
Licence type governing the use and redistribution of the software

LGPLv2.1, Ruby Licence

Apache License 2.0

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)

No

Yes

Robot can access Python's mock library for mocking
Grouping
Allows organizing tests in groups

No

Yes

One can create a test suite with Robot
Other
Other useful information about the testing framework