Use ruff for linting

ruff does the job of flake8, pep8, pycodestyle, isort, and more while
supporting pyproject.toml configuration - better, faster, stronger.

Migrate flake8 config from setup.cfg to ruff config in pyproject.toml.

Also bump versions in .pre-commit-config.yml to latest.

Author: yac

.pre-commit-config.yaml

@@ -1,7 +1,7 @@
 # Pre-commit configuration matching GitHub CI exactly
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.6.0
+    rev: v6.0.0
     hooks:
       - id: trailing-whitespace
         exclude: ^(test_env/|\.tox/|venv/|env/)
@@ -11,22 +11,13 @@ repos:
       - id: check-added-large-files
       - id: check-merge-conflict
 
-  - repo: https://github.com/pycqa/flake8
-    rev: 7.1.1
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.14.8
     hooks:
-      - id: flake8
-        exclude: ^(test_env/|\.tox/|venv/|env/)
-
-  - repo: https://github.com/pycqa/isort
-    rev: 5.13.2
-    hooks:
-      - id: isort
-        args: [--profile=black]
-        # Make isort compatible with black formatting
-        exclude: ^(test_env/|\.tox/|venv/|env/)
+      - id: ruff-check
 
   - repo: https://github.com/psf/black
-    rev: 24.10.0
+    rev: 25.12.0
     hooks:
       - id: black
         # GitHub CI runs: black --check . (no custom line-length, uses default)

demo/requirements.txt

@@ -10,7 +10,6 @@ maxminddb-geolite2
 model_bakery
 django-concurrent-test-helper
 freezegun
-flake8
 psycopg2-binary
 internet-sabotage3>=0.1.6
 django_coverage_plugin

pyproject.toml

@@ -62,3 +62,24 @@ include = ["plans", "plans.*", "plans_i18n"]
 [tool.pytest.ini_options]
 python_files = "test*.py"
 addopts = "--tb=short"
+
+[tool.ruff]
+line-length = 120
+exclude = [
+    "env",
+    "venv",
+    ".venv",
+    ".tox",
+    "bow",
+    "docs",
+    "migrations",
+    "node_modules",
+    "static",
+]
+
+[tool.ruff.lint]
+select = ["E", "W", "F", "N", "I"]
+ignore = [
+    "N802",  # function name should be lowercase
+    "N806",  # variable in function should be lowercase
+]