/tryceratops

A linter to prevent exception handling antipatterns in Python (limited only for those who like dinosaurs).

Primary LanguagePythonMIT LicenseMIT

Prevent Exception Handling AntiPatterns in Python

Actions Status PyPI Semantic Release GitHub Downloads Code style: black try/except style: tryceratops Follow guilatrova

Inspired by this blog post. I described the building process of this tool here.

“For those who like dinosaurs 🦖 and clean try/except ✨ blocks.”

Summary

Installation and usage

Installation

pip install tryceratops

OR

poetry add -D tryceratops

Usage

tryceratops [filename or dir...]

You can enable experimental analyzers by running:

tryceratops --experimental [filename or dir...]

You can ignore specific violations by using: --ignore TCXXX repeatedly:

tryceratops --ignore TC201 --ignore TC202 [filename or dir...]

You can exclude dirs by using: --exclude dir/path repeatedly:

tryceratops --exclude tests --exclude .venv [filename or dir...]

You can also autofix some violations:

tryceratops --autofix [filename or dir...]

example

flake8 Plugin

🦖 Tryceratops is also a plugin for flake8, so you can:

❯ flake8 --select TC src/tests/samples/violations/call_raise_vanilla.py
src/tests/samples/violations/call_raise_vanilla.py:13:9: TC002 Create your own exception
src/tests/samples/violations/call_raise_vanilla.py:13:9: TC003 Avoid specifying long messages outside the exception class
src/tests/samples/violations/call_raise_vanilla.py:21:9: TC201 Simply use 'raise' without specifying exception object again

Violations

All violations and its descriptions can be found in docs.

Autofix support

So far, autofix only supports violations: TC200, TC201, and TC400.

Ignoring violations

If you want to ignore a violation in a specific file, you can either:

  • Add a comment with noqa to the top of the file you want to ignore
  • Add a comment with noqa to the line you want to ignore
  • Add a comment with noqa: CODE to the line you want to ignore a specific violation

Example:

def verbose_reraise_1():
    try:
        a = 1
    except Exception as ex:
        raise ex  # noqa: TC202

Configuration

You can set up a pyproject.toml file to set rules. This is useful to avoid reusing the same CLI flags over and over again and helps to define the structure of your project.

Example:

[tool.tryceratops]
exclude = ["samples"]
ignore = ["TC002", "TC200", "TC300"]
experimental = true

CLI flags always overwrite the config file.

Pre-commit

If you wish to use pre-commit, add this:

  - repo: https://github.com/guilatrova/tryceratops
    rev: v1.1.0
    hooks:
      - id: tryceratops

Show your style

try/except style: tryceratops

Add this fancy badge to your project's README.md:

[![try/except style: tryceratops](https://img.shields.io/badge/try%2Fexcept%20style-tryceratops%20%F0%9F%A6%96%E2%9C%A8-black)](https://github.com/guilatrova/tryceratops)

Extra Resources

If you want to read more about:

Contributing

Thank you for considering making Tryceratops better for everyone!

Refer to Contributing docs.

Change log

See CHANGELOG.

License

MIT

Credits

Thanks to God for the inspiration 🙌 ☁️ ☀️

The black project for insights.