pytest vs Testing Library

Free and open source

Free and open source

Free and open source. You pay in engineering time and CI minutes.

Free and open source. You pay in engineering time and CI minutes.

Everything, self-hosted

Everything, self-hosted

Category standard

pytest-dev · since 2004

Category standard

OSS community · since 2018

• Fixtures are the best dependency-injection model in any test framework, and they compose cleanly.
• Assertion introspection produces genuinely useful failure output from a plain assert.
• Vast plugin ecosystem — pytest-xdist, pytest-cov, pytest-asyncio, pytest-django.

• Tests survive refactors because they assert on user-visible output, not internals.
• Accessible-role queries push teams towards accessible markup as a side effect.
• One idiom across every major front-end framework.

• Fixture scope and ordering become genuinely hard to reason about in large suites.
• The magic that makes simple cases elegant makes complex cases opaque.
• Python only.

• Deliberately makes implementation-detail testing hard, which frustrates teams used to shallow rendering.
• Async utilities and act() warnings are a common source of confusion.
• Needs a runner and a DOM environment alongside it.

Essentially every Python project.

Any front-end team writing component tests, regardless of framework.