Testing & Mocking Packages
Testing frameworks, assertion libraries, and mocking tools for writing reliable unit, integration, and end-to-end tests (testify, pytest, Vitest).
Packages in Testing & Mocking
Kind
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pytest
The Python testing framework that makes writing small tests easy and scales to complex functional test suites.
Faker
Generate massive amounts of realistic fake data for testing, seeding, and mocking in JavaScript and TypeScript.
Cypress
Fast, easy, and reliable end-to-end and component testing for anything that runs in a browser.
mocha
The classic, battle-tested JavaScript test framework for Node.js and the browser, built around flexible async testing and pluggable reporters.
pluggy
The minimalist, production-ready plugin and hook system that powers pytest, tox, and devpi
assert
Node.js's assert module, ported to run in browsers and bundlers
Faker
A Python library that generates realistic fake data for testing, seeding, and anonymizing datasets across 70+ locales.
hypothesis
Property-based testing for Python that generates edge cases and shrinks failures to their simplest reproducing example.
fake-useragent
Up-to-date user-agent string faker backed by a real-world browser usage database, bundled offline.
fakeredis
A pure-Python, in-memory implementation of the Redis protocol for testing.
pytest-order
Pytest plugin for running tests in a specific, controllable order
chrome-remote-interface
A Node.js client for the Chrome DevTools Protocol, exposing every browser command, event, and type as a plain JavaScript API.
behave
A Python behavior-driven development framework that runs Gherkin feature files against step definitions written in plain Python.
testcontainers-python
Throwaway Docker containers for real integration tests, driven straight from Python.
pytest-html
A pytest plugin that turns your test run into an interactive, shareable HTML report.
mock
The rolling backport of Python's unittest.mock library
factory_boy
A versatile test fixtures replacement for Python, providing declarative factories for building complex test objects.
VCR.py
Record and replay HTTP interactions to speed up tests
MinkExtension
Mink browser-automation integration and configuration layer for the Behat BDD framework.
DeepEval
A Pytest-like open-source framework for unit-testing and evaluating LLM applications with research-backed metrics.
undetected-chromedriver
A drop-in Selenium Chrome WebDriver replacement that patches the chromedriver binary and browser fingerprint to evade bot-mitigation systems.
pywinauto
A Python library that drives Windows GUI apps by sending mouse, keyboard, and text-based actions to dialogs and controls.
nodriver
Async browser automation and web scraping that talks directly to Chromium via CDP, with no Selenium, WebDriver, or ChromeDriver required.
Mink
A PHP browser emulator abstraction that unifies web acceptance testing across drivers.
