chore(python): Use ruff instead of isort, flake8 and pyupgrade.

Use ruff instead of isort, flake8 and pyupgrade.

Improve ruff linting support by configuring it properly.
A lot of useful flake8 plugins are (partially) implemented
in ruff now. isort and pyupgrade reimplementations are also
available.

Enable the following ruff error codes:
  - pycodestyle: E, W
  - Pyflakes: F
  - flake8-bugbear: B
  - flake8-comprehensions: C4
  - flake8-docstrings: D
  - isort: I001
  - flake8-simplify: SIM
  - flake8-tidy-imports: TID
  - flake8-quotes: Q
  - pyupgrade: UP

This allows to quicly check all python code while working
on the code base as running black and ruff afterwards,
should do almost the same than the current linting
(black, isort, pyupgrade, flake8)

    black
    ruff .

flake8-docstrings general D1 error code is changed to all
the current error codes still available in the Polars
codebase, ordered from most common, to least common, so
it should be easier to make this list of needed error
codes to ignore, smaller.

    D105, D100, D103, D102, D104, D101,

For tests it is probably ok that they don't have a docstring,
so for those the specific doccstring error codes to ignore
are already added for those files so fixing the docstring
error codes for non-test python files will be easier down
the road:
  - tests/*/*.py: D100, D103
  - tests/docs/run_doc_examples.py: D101, D102, D103
  - tests/parametric/__init__.py: D104
  - tests/slow/__init__.py: D104

.github/workflows/lint-python.yaml

@@ -33,9 +33,7 @@ jobs:
         run: |
           black --check .
           blackdoc --check .
-          isort --check .
-          pyupgrade --py37-plus `find . -name "*.py" -type f`
-          flake8
+          ruff .
       - name: Set up Rust
         uses: dtolnay/rust-toolchain@master
         with:

py-polars/Makefile

@@ -26,14 +26,12 @@ build-release: venv  ## Compile and install a faster Polars binary
 
 .PHONY: fmt
 fmt: venv  ## Run autoformatting and linting
-	$(VENV_BIN)/isort .
 	$(VENV_BIN)/black .
 	$(VENV_BIN)/blackdoc .
-	$(VENV_BIN)/pyupgrade --py37-plus `find polars tests docs -name "*.py" -type f`
+	$(VENV_BIN)/ruff .
 	cargo fmt --all
 	-dprint fmt
 	-$(VENV_BIN)/mypy
-	-$(VENV_BIN)/flake8
 
 .PHONY: clippy
 clippy:  ## Run clippy

py-polars/polars/__init__.py

@@ -65,8 +65,10 @@ def version() -> str:
 from polars.internals import BatchedCsvReader
 
 # TODO remove need for wrap_df
-from polars.internals.dataframe import wrap_df  # noqa: F401
-from polars.internals.dataframe import DataFrame
+from polars.internals.dataframe import (
+    DataFrame,
+    wrap_df,  # noqa: F401
+)
 from polars.internals.expr.expr import Expr
 from polars.internals.functions import (
     align_frames,
@@ -125,9 +127,9 @@ def version() -> str:
     struct,
     sum,
     tail,
+    var,
 )
 from polars.internals.lazy_functions import to_list as list
-from polars.internals.lazy_functions import var
 from polars.internals.lazyframe import LazyFrame
 
 # TODO: remove need for wrap_s

py-polars/polars/internals/anonymous_scan.py

@@ -9,7 +9,7 @@
 from polars.dependencies import pyarrow as pa
 
 
-def _deser_and_exec(
+def _deser_and_exec(  # noqa: D417
     buf: bytes, with_columns: list[str] | None, *args: Any
 ) -> pli.DataFrame:
     """
@@ -84,7 +84,7 @@ def _scan_ds(
     )
 
 
-def _scan_ipc_impl(
+def _scan_ipc_impl(  # noqa: D417
     uri: str, with_columns: list[str] | None, *args: Any
 ) -> pli.DataFrame:
     """
@@ -117,7 +117,7 @@ def _scan_ipc_fsspec(
     return pli.LazyFrame._scan_python_function(schema, func_serialized)
 
 
-def _scan_parquet_impl(
+def _scan_parquet_impl(  # noqa: D417
     uri: str, with_columns: list[str] | None, *args: Any
 ) -> pli.DataFrame:
     """

py-polars/polars/internals/series/utils.py

@@ -25,7 +25,7 @@ class _EmptyBytecodeHelper:
     def __init__(self) -> None:
         # generate bytecode for empty functions with/without a docstring
         def _empty_with_docstring() -> None:
-            """"""
+            """"""  # noqa: D419
 
         def _empty_without_docstring() -> None:
             pass

py-polars/pyproject.toml

@@ -26,9 +26,6 @@ all = [
   "polars[pyarrow,pandas,numpy,fsspec,connectorx,xlsx2csv,deltalake,timezone,matplotlib]",
 ]
 
-[tool.isort]
-profile = "black"
-
 [tool.mypy]
 files = ["polars", "tests"]
 namespace_packages = true
@@ -88,4 +85,73 @@ exclude_lines = [
 ]
 
 [tool.ruff]
+# Assume Python 3.7.
+target-version = "py37"
+
 line-length = 88
+
+extend-exclude = [
+  # Automatically generated test artifacts
+  "venv/",
+  "target/",
+]
+
+select = [
+  # pycodestyle
+  "E",
+  "W",
+  # Pyflakes
+  "F",
+  # flake8-bugbear
+  "B",
+  # flake8-comprehensions
+  "C4",
+  # flake8-docstrings
+  "D",
+  # isort
+  "I001",
+  # flake8-simplify
+  "SIM",
+  # flake8-tidy-imports
+  "TID",
+  # flake8-quotes
+  "Q",
+  # pyupgrade
+  "UP",
+]
+ignore = []
+
+extend-select = ["D"]
+extend-ignore = [
+  # pydocstyle: http://www.pydocstyle.org/en/stable/error_codes.html
+  # numpy convention with a few additional lints
+  "D107",
+  "D203",
+  "D212",
+  "D402",
+  "D415",
+  "D416",
+  # TODO: Remove errors below to further improve docstring linting
+  # Ordered from most common to least common errors.
+  "D105",
+  "D100",
+  "D103",
+  "D102",
+  "D104",
+  "D101",
+]
+
+[tool.ruff.flake8-tidy-imports]
+ban-relative-imports = "all"
+
+[tool.ruff.flake8-quotes]
+inline-quotes = "double"
+docstring-quotes = "double"
+multiline-quotes = "double"
+
+[tool.ruff.per-file-ignores]
+"polars/datatypes.py" = ["B019"]
+"tests/*/*.py" = ["D100", "D103"]
+"tests/docs/run_doc_examples.py" = ["D101", "D102", "D103"]
+"tests/parametric/__init__.py" = ["D104"]
+"tests/slow/__init__.py" = ["D104"]

py-polars/requirements-lint.txt

@@ -1,10 +1,3 @@
 black==22.8.0
 blackdoc==0.3.7
-flake8==5.0.4
-flake8-bugbear==22.10.25
-flake8-comprehensions==3.10.0
-flake8-docstrings==1.6.0
-flake8-simplify==0.19.3
-flake8-tidy-imports==4.8.0
-isort==5.10.1
-pyupgrade==3.1.0
+ruff==0.0.208

py-polars/tests/unit/test_df.py

@@ -1,4 +1,3 @@
-# flake8: noqa: W291
 from __future__ import annotations
 
 import sys