Nifty pytest

A pytest test explorer with saved run configurations, marker filters, real assertion diffs, rerun-failed and slowest-test reports.

Maintained. No sign-in. No telemetry. Works in VS Code, Cursor, Windsurf, VSCodium and other editors that use Open VSX.

Features

A failing assert on two dicts opens a key-by-key diff under the test, with parametrized cases and markers in the Test Explorer

Show Slowest Tests lists the last run's tests by duration

Your pytest suite in the Test Explorer. Files, classes, tests and every parametrized case, with run buttons in the gutter and each test's markers (@slow, @db) shown next to it. Discovery uses pytest itself, so conftest.py, plugins and pytest.ini / pyproject.toml settings all apply.
Assertion diffs that are actually readable. When assert result == expected fails, the failure opens VS Code's side-by-side diff of the two values, pretty-printed, not a wall of E lines.
Saved run configurations. Define "Fast", "Integration only" or "With coverage" once in settings and pick them from the Run and Debug dropdowns. Each has its own arguments and environment variables.
Marker and keyword runs. Run Tests with Marker… lists the markers used in your suite (and their not versions). Run Tests Matching… runs a -k expression.
Rerun Failed Tests in one click from the Test Explorer toolbar.
Show Slowest Tests from the last run, and jump straight to them.
Debug any test with the Python Debugger, including through a saved configuration.
Setup and teardown errors are shown as errors, skips and xfails as skipped, and each test's captured output is attached to it.
Uses your interpreter: the one selected in the Python extension (venv, conda, uv, Poetry), or nifty.pytest.pythonPath.

Example configuration

// .vscode/settings.json
"nifty.pytest.configurations": [
  { "name": "Fast", "args": ["-m", "not slow", "-x"] },
  { "name": "Integration", "args": ["-m", "integration"], "env": { "DATABASE_URL": "postgres://localhost/test" } }
]

Commands

Command	What it does
`Nifty pytest: Refresh Tests`	Rediscover tests
`Nifty pytest: Run All Tests`	Run the whole suite
`Nifty pytest: Run Tests with Marker…`	Run tests selected by a marker expression (`-m`)
`Nifty pytest: Run Tests Matching (-k)…`	Run tests whose names match a keyword expression
`Nifty pytest: Rerun Failed Tests`	Run only the tests that failed last time
`Nifty pytest: Show Slowest Tests`	The slowest tests of the last run
`Nifty pytest: Add Run Configuration…`	Save a named set of pytest arguments

Settings

Setting	Default	What it does
`nifty.pytest.pythonPath`	`""`	Interpreter with pytest installed. Empty uses the Python extension's selection
`nifty.pytest.args`	`[]`	Arguments added to every run and discovery
`nifty.pytest.env`	`{}`	Environment variables for every run
`nifty.pytest.configurations`	`[]`	Saved run configurations (see above)
`nifty.pytest.autoDiscover`	`true`	Discover tests on startup and when test files change

Using it alongside the Python extension

Microsoft's Python extension also lists pytest tests. To avoid seeing each test twice, turn its runner off with "python.testing.pytestEnabled": false in the workspace, or hide one of the two in the Test Explorer's filter.

Install

VS Code: search for "Nifty pytest" in the Extensions view, or install from the Visual Studio Marketplace.
Cursor, Windsurf, VSCodium, Kiro, Antigravity: install from Open VSX.

Privacy

This extension collects no telemetry and needs no account.

More Nifty tools

Nifty Python Profiler: cProfile Hotspots Inline: Profile Python scripts and pytest runs with cProfile: hotspot table, call counts and timings inline next to each function. (Open VSX)
Nifty Code Runner: Run Code in 25+ Languages: Run the current file or selection in 25+ languages in the terminal, with input support, your own commands and no telemetry. (Open VSX)
Nifty Env: .env Files, Profiles & Secrets: Load .env files into terminals, tasks and debug sessions, switch between .env profiles, hide secret values on screen, and check .env against .env.example. (Open VSX)
Nifty Launch: launch.json Generator & Checker: Add debug configurations for what's in your project (npm scripts, tests, Python, Django, FastAPI, Go, .NET, Rust, browsers), build compounds, and catch broken launch.json references. (Open VSX)
Nifty Python Envs: venv, uv, conda & pyenv: See and manage every Python environment: project venvs (uv or venv), uv-managed Pythons, conda and pyenv. Create, activate in terminals, pick for the workspace, and manage packages. (Open VSX)
Nifty REST Client: .http Files & HTTP Requests: Send HTTP requests from .http files: variables, environments, request chaining, response viewer, cURL import and export, and history. No account, no cloud. (Open VSX)

See all 100+ Nifty extensions and web tools at https://getnifty.dev

Nifty pytest: pytest Test Explorer

Nifty