Modern tooling
uv, ruff, pyproject.toml, packaging, and current Python project workflows.
Configure ruff linter rules in pyproject.toml with Python
Reads an existing pyproject.toml and merges common ruff linter rules into the tool.ruff section using Python's tomllib.
import tomllib
from pathlib import Path
def configure_ruff_linter_rules(project_path: str = ".") -> dict:
"""Add common ruff linter rules to pyproject.toml if missing."""
pyproject_path = Path(project_path) / "pyproject.toml"
# Default config for ruff linter with practical rules
ruff_config = {
…How to Define Nox Sessions in Python
Automate repetitive tasks like testing and linting with reusable Nox sessions.
import nox
@nox.session(python=["3.9", "3.10"])
def tests(session):
session.install("pytest")
session.run("pytest")
@nox.session(python="3.9")
def lint(session):
session.install("ruff")
session.run("ruff", "check", ".")
if __name__ == "__main__":
print("Nox sessions defined: tests, lint")
…How to Mock isort Output to Test Import Sorting in Python
Uses isort with check mode and a unittest mock to verify whether a Python source string has correctly sorted imports.
import isort
from unittest.mock import patch
code = """
import os
import sys
import json
import pathlib
"""
def check_imports_sorted(code_str):
with patch("isort.api.output") as mock_output:
isort.code(code_str, check=True, show_diff=True)
return mock_output.called
if __name__ == "__main__":
…How to configure ruff linter rules in pyproject.toml with Python
This Python script generates a pyproject.toml file with ruff linter rules, including selected and ignored rules, per-file ignores, and complexity limits.
from pathlib import Path
def configure_ruff_rules(project_dir: str = "my_project") -> None:
"""Create a pyproject.toml with ruff linter rules for mock usage."""
pyproject_path = Path(project_dir) / "pyproject.toml"
pyproject_path.parent.mkdir(parents=True, exist_ok=True)
config = """[tool.ruff]
line-…Lint a Dockerfile with a Mock Hadolint in Python
A lightweight Python script that simulates hadolint by scanning Dockerfile text for common lint rules and printing violations.
import subprocess
import tempfile
from pathlib import Path
def lint_dockerfile(content: str) -> list[str]:
"""Mock hadolint by checking a few rules and returning violations."""
violations = []
lines = content.splitlines()
for idx, line in enumerate(lines, start=1):
stripped = line.strip()
…Makefile Targets for lint, test, and build in Python
This Python script defines common Makefile targets (lint, test, build) as subprocess commands, printing each target's command and executing them with error checking.
import subprocess
TARGETS = {
"lint": ["ruff", "check", "."],
"test": ["pytest", "-q"],
"build": ["python", "-m", "build"],
}
def run(target: str) -> None:
if target not in TARGETS:
raise ValueError(f"Unknown target: {target}")
print(f"Running {target}...")
subprocess.run(TARGETS[tar…Browse by section
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Modern tooling — Python code examples
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