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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unittest-xml-reporting
A unittest test runner that saves results as xUnit/JUnit XML for CI systems to consume.
Cucumber Expressions
A human-readable alternative to regular expressions for matching Gherkin step text
cypress-log-to-output
A Cypress plugin that pipes browser console logs and Chrome DevTools log entries into your terminal's stdout during test runs.
pytest-aiohttp
A pytest plugin with fixtures for testing aiohttp servers and clients, with cleanup handled for you.
Behat Page Object Extension
A Behat extension that brings the Page Object pattern to your BDD tests, auto-injecting typed page and element objects into context step definitions.
pytest-reportlog
A pytest plugin that streams test session events to a JSON Lines file for real-time monitoring and processing.
wiremock
Python client and Testcontainers integration for driving a WireMock server from tests
psalm/plugin-phpunit
A Psalm static analysis plugin that understands PHPUnit test classes, mocks, and data providers.
pytest-pylint
Run pylint checks as pytest test items, failing your build on configurable pylint rule severities.
codspeed-criterion-compat
Drop-in Criterion.rs compatibility layer that runs Rust benchmarks under CodSpeed.
OpenFeature LocalStorage Provider
An OpenFeature provider that resolves feature flags from the browser's localStorage for instant client-side overrides.
datatest-stable
A Rust test harness for file-driven, data-driven tests that runs on stable Rust.
kgb
Function spies for Python unit tests that intercept, record, and reroute calls without heavy-handed mocking.
allocation-counter
A Rust library that runs code while counting heap allocations, for profiling and allocation-budget assertions.
get-it
Composable HTTP request library for Node.js, browsers, Deno, Bun, and edge runtimes
antithesis-sdk-rust
Rust SDK for the Antithesis autonomous testing platform: define test-property assertions, request platform-controlled randomness, and mark lifecycle milestones for fault-injection runs.
memory-level
In-memory abstract-level database for Node.js and browsers, backed by a fully persistent red-black tree.
storybook-vue3-router
A Storybook decorator that wraps Vue 3 components in vue-router so routing-aware stories render, navigate, and test correctly.
tag-expressions
A small boolean-expression parser and evaluator for selecting Gherkin scenarios by tag, used by behave and other Cucumber-family test runners.
minimalistic-assert
A zero-dependency JavaScript assertion module for throwing errors on falsy values and loose equality checks.
pseudolocale
Idempotent pseudolocalization library that deterministically mutates strings to surface i18n bugs before real translation begins.
pytest-flake8
A pytest plugin that runs flake8 PEP8 and style checks against your Python files as part of the normal test suite.
