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
Sort:Used by Most Apps
SWE-bench
Benchmark harness that evaluates whether a language model can actually resolve real-world GitHub issues.
factory_boy
A versatile test fixtures replacement for Python, providing declarative factories for building complex test objects.
uvu
An extremely fast, lightweight test runner for Node.js and the browser, with optional browser-safe assertions.
VCR.py
Record and replay HTTP interactions to speed up tests
doctrine/data-fixtures
Manage and load data fixtures for any Doctrine object manager
httpexpect
A chainable Go library for declarative, end-to-end HTTP and REST API testing.
deepdiff
Deep difference, search, and hashing for any nested Python object, with deltas you can serialize and replay.
martian
A programmable HTTP/1.1 proxy for Go, used to inspect, mutate, and verify requests and responses via composable modifiers.
leaktest
A small Go package that detects leaked goroutines in tests by diffing stack snapshots taken before and after each test runs.
dhat
Heap profiling, ad hoc profiling, and heap-usage testing for Rust programs, in the style of Valgrind's DHAT.
@sinonjs/fake-timers
Deterministic fake implementations of setTimeout, setInterval, Date, and other timer APIs for fast, reliable JavaScript tests.
Nuxt Test Utils
Official testing toolkit for Nuxt apps, with Suspense-aware component mounting and real e2e fixtures.
pytest-cases
Separate test code from test cases in pytest, with fixture unions and parametrization goodies for readable, reusable test suites.
sqllogictest
A Rust parser and runner for sqllogictest files that verify SQL database correctness
pytest-repeat
A pytest plugin for repeating tests a set number of times
similar-asserts
assert_eq!-style Rust macros with colorized diff output for readable test failures.
libtest-mimic
Build a custom Rust test harness that looks and behaves like rustc's built-in test runner
MinkExtension
Mink browser-automation integration and configuration layer for the Behat BDD framework.
node-geckodriver
An npm wrapper that downloads, manages, and launches Mozilla's Geckodriver binary for Firefox WebDriver automation in Node.js.
portpicker
A tiny Rust crate that picks a free network port unused on both TCP and UDP.
@cypress/browserify-preprocessor
Cypress file preprocessor that bundles spec and support files with Browserify
lit
LLVM's portable command-line tool for discovering, running, and summarizing test suites.
Locust
An open-source load-testing tool that lets you define user behavior in plain Python.
pydevd-pycharm
PyCharm build of the pydevd debugger for remote Python debugging
