gaze-py 0.4.0

Python-native GazeCRAP analysis engine

gaze-py

gaze-py is a Python-native port of gaze, the GazeCRAP analysis engine. It detects observable side effects in Python functions using AST-only static analysis (no code execution, no imports of analysed modules), classifies each effect as contractual or incidental using a five-signal confidence engine, and computes CRAP and GazeCRAP scores to surface functions that are both complex and under-tested. The output is schema-compatible with the Go gaze implementation.

Requirements

• Python 3.11+

Installation

# Run without installing (recommended for one-off use)
uvx --from gaze-py gazepy --help

# Permanent install
uv tool install gaze-py

# Or with pip
pip install gaze-py

Basic usage

# Analyse a source directory (CRAP will be null — no coverage provided)
gazepy analyze src/

# JSON output (default)
gazepy analyze src/ --format=json

# Human-readable text output (one line per function)
gazepy analyze src/ --format=text

# CRAP scoring — auto-runs pytest for coverage
gazepy crap src/

# CRAP scoring with a pre-generated coverage report
gazepy crap src/ --coverprofile cov.json

# Assess test quality and compute GazeCRAP scores
gazepy quality src/

# Scaffold OpenCode agent and command files into .opencode/
gazepy init

CRAP scoring with gazepy crap

CRAP scoring requires line coverage data. The crap command can collect coverage automatically by running pytest, or accept a pre-generated coverage.py JSON report:

# Auto-run pytest and collect coverage (requires pytest-cov)
gazepy crap src/

# Use a pre-generated coverage report (recommended in CI to avoid a double test run)
pytest --cov=your_package --cov-report=json:cov.json
gazepy crap src/ --coverprofile cov.json

# Fail CI if crapload exceeds a threshold
gazepy crap src/ --max-crapload 30

When coverage is provided, the line_coverage and crap fields are populated in the output. When omitted, those fields are null (not 0.0) — null means "not measured", not "zero coverage".

The analyze command detects side effects only — it does not compute CRAP scores. Use gazepy crap for CRAP scoring.

Quality assessment with gazepy quality

gazepy quality runs the full O1 pipeline: pairs test functions to their production targets, detects assertion sites, maps assertions to detected side effects, and computes GazeCRAP using contract coverage (the fraction of contractual effects covered by tests).

# Assess test quality — auto-discovers tests/ directory
gazepy quality src/

# Explicit tests directory
gazepy quality src/ --tests tests/

# JSON output
gazepy quality src/ --format=json

# Fail CI if average contract coverage drops below a threshold
gazepy quality src/ --min-contract-coverage 80

Understanding the output

Each function in the output includes:

Field	Description
side_effects	List of detected observable side effects with type, tier, and classification
complexity	McCabe cyclomatic complexity
line_coverage	Fraction of lines covered (0.0–1.0), or null if not provided
crap	CRAP score (complexity² × (1 − coverage)³ + complexity), or null
gaze_crap	GazeCRAP score using contract coverage; populated by gazepy quality
quadrant	Q1–Q4 classification based on CRAP and GazeCRAP; populated by gazepy quality
fix_strategy	Recommended action: add_tests, decompose_and_test, or decompose
contract_coverage	Fraction of contractual effects covered by tests; populated by gazepy quality

The summary section includes recommended_actions — up to 20 functions sorted by priority (add_tests → decompose_and_test → decompose) that exceed the CRAP threshold.

Current limitations

• Effect confidence range deferred: The effect_confidence_range field is present in the output schema (as null) but not yet computed.

Releasing

Releasing a new version

1. Bump version in pyproject.toml and __version__ in src/gaze_py/__init__.py in a PR. Merge to main.
2. Go to GitHub Actions → Release → Run workflow.
3. Enter the tag matching the version (e.g. v0.3.0).
4. Approve the pypi environment gate if configured.
5. The workflow validates, tags, builds, and publishes automatically.