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

unittest

https://docs.Python.org/3/library/unittest.html

RSpec

https://rspec.info
Programming language

Python

Ruby

Category

Unit Testing

Unit Testing, Intergration Testing

General info

unittest is a unit testing framework for Python

The unittest test framework is Python’s xUnit style framework. It is a standard module that is bundled with Python and supports the automation and aggregation of tests and common setup and shutdown code for them.

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.

Yes

unittest is a xUnit style frameworkfor Python, it was previously called PyUnit.

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

Front-end functionality and behaviour can be tested by unittest.

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

Since the webserver funtionalities have their own features and each feature has its own functions, we can write tests with unittest to test each function

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

By use of the 'setUp()' function which is called to prepare the test fixture

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

unittest allows you to group your initialization code into a setUp function and clean up code in a tearDown function

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

unittest contains generator methods in the module 'unittest.TestCase'

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

MIT License

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

Mocks are available from the library unittest.mock which allows you to replace parts of your system under test with mock objects

Yes

Available through rspec-mocks gem.
Grouping
Allows organizing tests in groups

Yes

One can build suites either manually or use test discovery to build the suite automatically by scanning a directory

Yes

Allows declaring example groups and contexts.
Other
Other useful information about the testing framework