Cypress.io vs pytest comparison of testing frameworks
What are the differences between Cypress.io and pytest?

Cypress.io

https://www.cypress.io/

pytest

https://docs.pytest.org/en/latest/
Programming language

JavaScript

Python

Category

End-to-End Testing, Intergration Testing, Unit Testing

Unit Testing

General info

Cypress users are typically developers or QA engineers building web applications using modern JavaScript frameworks. This is the top tier UI automation framework which outsmarts Selenium based frameworks in most of the aspects!

Cypress enables you to write all types of tests: 1. End-to-end tests; 2. Integration tests; 3. Unit tests; 4. Cypress can test anything that runs in a browser; Apart from that Cypress provides the Dashboard facility for CI/CD

Pytest is the TDD 'all in one' testing framework for Python

Pytest is a powerful Python testing framework that can test all and levels of software. It is considered by many to be the best testing framework in Python with many projects on the internet having switched to it from other frameworks, including Mozilla and Dropbox. This is due to its many powerful features such as ‘assert‘ rewriting, a third-party plugin model and a powerful yet simple fixture model.
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

This is the primary goal of Cypress, it tests anything that runs in a browser and works to build great user experience that is it tests the applications flow from beginning to end from a user perspective. It is built to handle modern JavaScript frameworks especially well and also works equally well on older server rendered pages or applications

Yes

pytest can test any part of the stack including front-end components
Server-side
Allows testing the bahovior of a server-side code

Yes

Although Cypress is not a general automation framework, nor is it a unit testing framework for your back-end services, It can test back-end behaviours for example using cy.task() command which provides a way for running Node code, so you can take actions necessary for your tests outside of the scope of Cypress

Yes

pytest is powerful enough to test database and server components and functionality
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

Cypress has inbuilt fixtures capabilities or example using the command 'cy.fixture(filePath)' loads a fixed set of data located in a file

Yes

Pytest has a powerful yet simple fixture model that is unmatched in any other testing framework.
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

Cypress can create group fixtures using the 'cy.fixture' command

Yes

Pytest's powerful fixture model 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.

N/A

Yes

pytest has a hook function called pytest_generate_tests hook which is called when collecting a test function and one can use it to generate data
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

Cypress comes built in with the ability to stub and spy with cy.stub(), cy.spy(), It also automatically bundles 'sinon', 'lolex' and 'sinon-chai' which all work to give Cypress mocking capabilities

Yes

By either using unittest.mock or using pytest-mock a thin wrapper that provides mock functionality for pytest
Grouping
Allows organizing tests in groups

Yes

Cypress allows you to configure tests into groups however there is no way currently to run the groups

Yes

Tests can be grouped with pytest by use of markers which are applied to various tests and one can run tests with the marker applied
Other
Other useful information about the testing framework