simplistix§testfixtures

Imported from gencau/test-practices-agent-configurations (dataset/repos/simplistix§testfixtures/AGENTS.md). Install upstream with npx skills add gencau/test-practices-agent-configurations --skill simplistix§testfixtures. Copyright stays with the author.

Agent Instructions

Principles

• Done means green — a change is only complete when ./happy.sh exits 0; do not commit until it does.
• No unrelated failures — if ./happy.sh fails on something unrelated to your changes, do NOT assume it is a pre-existing problem and proceed anyway. Stop immediately and ask the user how to proceed.
• Docs for everything public — new functionality or public API changes must have accompanying docs in docs/*.rst
• Type-annotate public APIs — all public functions and classes need type annotations; mypy is the gate
• Use compare() in tests — never use bare assert statements; always use compare(actual, expected=...) for assertions

Project Overview

Testfixtures is a Python testing utilities library. Features: object comparison with diff output, mocking/replacement, logging capture, temporary directories, datetime mocking, exception/warning testing, Django and Twisted support.

Environment

uv sync --all-extras --all-groups              # setup or after pulling
rm -rf .venv && uv sync --all-extras --all-groups  # full reset

Commands

./happy.sh                                         # all checks — required before commit
uv run pytest                                      # all tests + doctests
uv run pytest tests/test_comparison.py             # single file
uv run pytest --cov=testfixtures --cov-report=term-missing  # with coverage
uv run mypy src/testfixtures                       # type checking
make -C docs html                                  # build docs (use this, not sphinx-build directly)
uv build                                           # build sdist + wheel

Architecture

src/testfixtures/ — all source. Key modules:

• comparison.py — compare(), diff(), Comparison, StringComparison, RoundComparison, etc.
• replace.py — Replacer, replace() decorators
• logcapture.py — LogCapture
• datetime.py — mock_datetime, mock_date, mock_time
• tempdirectory.py — temporary directory management
• shouldraise.py — ShouldRaise, should_raise
• shouldwarn.py — ShouldWarn, ShouldNotWarn
• django.py, twisted.py — framework-specific support
• __init__.py — main API exports

Config: pyproject.toml (optional deps for Django, Sybil, Twisted).