Pytest

Install

Create project using --package in uv:

uv init my-project --package

Install pytest as a dev dependency:

uv add pytest --dev

Directory Structure

• Create a 'tests' folder parallel to 'src' folder
• Mirror your src folder structure
• Pytest automatically discovers files that match test_*.py
• Test function names should start with test_

  my_app/
  ├── pyproject.toml
  ├── src/
  │   └── my_app/
  │       ├── __init__.py
  │       ├── core/
  │       │   ├── __init__.py
  │       │   └── engine.py
  │       ├── utils/
  │       │   ├── __init__.py
  │       │   └── math_utils.py
  │       └── main.py
  └── tests/
      ├── __init__.py
      ├── core/
      │   ├── __init__.py    # optional
      │   └── test_engine.py
      ├── utils/
      │   ├── __init__.py    # optional
      │   └── test_math_utils.py
      └── test_main.py
  

Example

# tests/test_math_utils.py
from my_app.utils.math_utils import add

def test_add():
    assert add(2, 3) == 5

Run Tests

Run tests using

uv run pytest

Show more detailed output

uv run pytest -v 

Run only tests in a specific file

uv run pytest test_app.py