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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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.
memlab
Meta's end-to-end framework for finding JavaScript memory leaks and analyzing heap snapshots
nodriver
Async browser automation and web scraping that talks directly to Chromium via CDP, with no Selenium, WebDriver, or ChromeDriver required.
expect.js
Minimalistic BDD-style assertion library for Node.js and the browser with chainable, readable syntax.
stateright
A Rust model checker and actor library for verifying distributed systems like Paxos and Raft.
afl.rs
Fuzz-test Rust code with AFLplusplus using the afl crate's fuzz macros and cargo-afl tooling.
typeguard
Run-time type checking for Python functions and objects using PEP 484 annotations.
Mink
A PHP browser emulator abstraction that unifies web acceptance testing across drivers.
pytest-sugar
A pytest plugin that replaces the default test runner output with a live progress bar, instant failure display, and colorized results.
libtmux
A typed, object-oriented Python API for scripting and automating tmux servers, sessions, windows, and panes.
OpenEvals
Prebuilt evaluators and LLM-as-judge scorers for testing the quality of LLM application outputs.
user-agents
A JavaScript library that generates realistic, frequency-weighted random user agents and browser fingerprints from a dataset refreshed daily.
python-devtools
Python's missing debug print command, plus pretty formatting, timing, and pytest helpers.
Shuttle
A Rust library for testing concurrent code by controlling and randomizing thread scheduling to reliably surface race conditions.
Behat Gherkin
A PHP parser for the Gherkin BDD language with support for 40+ natural languages.
time-machine
Travel through time in your Python tests by mocking datetime and time at the C level.
allure-pytest
A pytest plugin that generates rich, interactive Allure test reports with steps and attachments
pytest-randomly
Pytest plugin that randomly orders tests and controls random.seed for reproducible, dependency-flushing test runs.
pytest-flask
A pytest plugin with ready-made fixtures for testing Flask applications end to end.
pytest-pretty
An opinionated pytest plugin that makes test output easier to read and failures faster to find and fix.
aiosmtpd
An asyncio-based SMTP and LMTP server implementation for Python, built to mock mail servers in tests and run lightweight custom relays.
Laravel Test Assertions
Extra PHPUnit assertions and matchers for testing Laravel applications.
