TheRock/rocm-systems/projects/rocprofiler-compute/.ai/rules/ruff-tooling.md

Ruff and Tooling Rules — AI-Authoritative Reference

These rules summarize the project's automated linting and formatting requirements. Canonical configuration: pyproject.toml

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Line Length

Hard limit: 88 characters per line. This is enforced by ruff (line-length = 88 in pyproject.toml).

• Do not generate lines that exceed 88 characters.
• Break long function arguments, chained calls, or comments across multiple lines.
• Use implicit string concatenation or backslash continuation for long strings.

# Correct — argument list broken across lines
result = some_function(
    argument_one,
    argument_two,
    argument_three,
)

# Flagged by Ruff (E501)
result = some_function(argument_one, argument_two, argument_three, argument_four_long_name)

Enforced Ruff Rules

The following rules are enforced on all files in src/ (see pyproject.toml for full config):

Rule Set	Code	Requirement
Line length	E501	Maximum 88 characters per line
Type annotations	ANN	All function arguments and return values must have type hints (except self, cls, _ args)
Modern syntax	UP	Use f-strings, not .format() or %
Path handling	PTH	Use pathlib.Path, not os.path
Pyflakes	F	No unused imports or variables
pycodestyle	E, W	PEP 8 compliance
isort	I	Sorted imports

Quick Reference

Type Annotations

# Correct
def process_data(name: str, values: list[float]) -> dict[str, Any]:
    ...

# Flagged by Ruff (ANN)
def process_data(name, values):
    ...

String Formatting

# Correct
message = f"Processing {name}"

# Flagged by Ruff (UP)
message = "Processing {}".format(name)

Path Handling

# Correct
config_path = Path.cwd() / "config" / "settings.yaml"

# Flagged by Ruff (PTH)
config_path = os.path.join(os.getcwd(), "config", "settings.yaml")

Suppressing Rules

Use sparingly and only when genuinely necessary:

• # fmt: off / # fmt: on — disable/re-enable formatting for a block
• # fmt: skip — skip formatting for a single line
• # noqa: <RULE> — suppress a specific lint rule for a line

Running Ruff Locally

# Check for issues
ruff check .
ruff format --check .

# Auto-fix
ruff check --fix .
ruff format .

# Check specific rule set
ruff check --select ANN .