Switch to ruff instead of flake8. (#14633)

ruff is a flake8-compatible Python linter written in Rust.
It supports the flake8 plugins that we use and is significantly
faster in testing.

1 files changed, 42 insertions, 4 deletions

diff --git a/pyproject.toml b/pyproject.toml
index 3281441534..37b9ab3a77 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -40,6 +40,46 @@ target-version = ['py37', 'py38', 'py39', 'py310']
 # https://black.readthedocs.io/en/stable/usage_and_configuration/file_collection_and_discovery.html#gitignore
 # Use `extend-exclude` if you want to exclude something in addition to this.
 
+[tool.ruff]
+line-length = 88
+
+# See https://github.com/charliermarsh/ruff/#pycodestyle
+# for error codes. The ones we ignore are:
+#  E731: do not assign a lambda expression, use a def
+#  E501: Line too long (black enforces this for us)
+#
+# See https://github.com/charliermarsh/ruff/#pyflakes
+#  F401: unused import
+#  F811: Redefinition of unused
+#  F821: Undefined name
+#
+# flake8-bugbear compatible checks. Its error codes are described at
+# https://github.com/charliermarsh/ruff/#flake8-bugbear
+#  B019: Use of functools.lru_cache or functools.cache on methods can lead to memory leaks
+#  B023: Functions defined inside a loop must not use variables redefined in the loop
+#  B024: Abstract base class with no abstract method.
+ignore = [
+    "B019",
+    "B023",
+    "B024",
+    "E501",
+    "E731",
+    "F401",
+    "F811",
+    "F821",
+]
+select = [
+    # pycodestyle checks.
+    "E",
+    "W",
+    # pyflakes checks.
+    "F",
+    # flake8-bugbear checks.
+    "B0",
+    # flake8-comprehensions checks.
+    "C4",
+]
+
 [tool.isort]
 line_length = 88
 sections = ["FUTURE", "STDLIB", "THIRDPARTY", "TWISTED", "FIRSTPARTY", "TESTS", "LOCALFOLDER"]
@@ -274,12 +314,10 @@ all = [
 ]
 
 [tool.poetry.dev-dependencies]
-## We pin black so that our tests don't start failing on new releases.
+# We pin black so that our tests don't start failing on new releases.
 isort = ">=5.10.1"
 black = ">=22.3.0"
-flake8-comprehensions = "*"
-flake8-bugbear = ">=21.3.2"
-flake8 = "*"
+ruff = "0.0.189"
 
 # Typechecking
 mypy = "*"