Adopt ruff and address lint

.github/dependabot.yml

@@ -1,8 +1,10 @@
 version: 2
 updates:
-  # Set update schedule for GitHub Actions
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
-      # Check for updates to GitHub Actions every weekday
+      interval: "weekly"
+  - package-ecosystem: "pip"
+    directory: "/"
+    schedule:
       interval: "weekly"

.github/workflows/python-tests.yml

@@ -39,12 +39,17 @@ jobs:
           pip install codecov coverage[toml]
           codecov
 
-  pre_commit:
+  test_lint:
+    name: Test Lint
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
       - uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
-      - uses: jupyterlab/maintainer-tools/.github/actions/pre-commit@v1
+      -  name: Run Linters
+         run: |
+          hatch run typing:test
+          hatch run lint:style
+          pipx run 'validate-pyproject[all]' pyproject.toml
 
   test_minimum_versions:
     name: Test Minimum Versions
@@ -116,7 +121,7 @@ jobs:
     if: always()
     needs:
       - build
-      - pre_commit
+      - test_lint
       - test_minimum_versions
       - test_prereleases
       - check_links

.pre-commit-config.yaml

@@ -1,3 +1,6 @@
+ci:
+  autoupdate_schedule: monthly
+
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
     rev: v4.4.0
@@ -15,61 +18,25 @@ repos:
       - id: check-builtin-literals
       - id: trailing-whitespace
 
-  - repo: https://github.com/psf/black
-    rev: 22.10.0
-    hooks:
-      - id: black
-        args: ["--line-length", "100"]
-
-  - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v0.991
-    hooks:
-      - id: mypy
-        args: ["--config-file", "pyproject.toml"]
-        additional_dependencies: [pytest, tornado, traitlets, jupyter_client, jupyter_server]
-        stages: [manual]
-
-  - repo: https://github.com/PyCQA/isort
-    rev: 5.10.1
-    hooks:
-      - id: isort
-        files: \.py$
-        args: [--profile=black]
-
-  - repo: https://github.com/abravalheri/validate-pyproject
-    rev: v0.10.1
+  - repo: https://github.com/python-jsonschema/check-jsonschema
+    rev: 0.19.2
     hooks:
-      - id: validate-pyproject
-        stages: [manual]
+      - id: check-github-workflows
 
   - repo: https://github.com/executablebooks/mdformat
     rev: 0.7.16
     hooks:
       - id: mdformat
+        additional_dependencies:
+          [mdformat-gfm, mdformat-frontmatter, mdformat-footnote]
 
-  - repo: https://github.com/asottile/pyupgrade
-    rev: v3.3.0
-    hooks:
-      - id: pyupgrade
-        args: [--py37-plus]
-
-  - repo: https://github.com/PyCQA/doc8
-    rev: v1.0.0
-    hooks:
-      - id: doc8
-        args: [--max-line-length=200]
-        stages: [manual]
-
-  - repo: https://github.com/john-hen/Flake8-pyproject
-    rev: 1.2.2
+  - repo: https://github.com/psf/black
+    rev: 22.10.0
     hooks:
-      - id: Flake8-pyproject
-        alias: flake8
-        additional_dependencies:
-          ["flake8-bugbear==22.6.22", "flake8-implicit-str-concat==0.2.0"]
-        stages: [manual]
+      - id: black
 
-  - repo: https://github.com/python-jsonschema/check-jsonschema
-    rev: 0.19.2
+  - repo: https://github.com/charliermarsh/ruff-pre-commit
+    rev: v0.0.165
     hooks:
-      - id: check-github-workflows
+      - id: ruff
+        args: ["--fix"]

jupyter_server_synchronizer/_version.py

@@ -10,7 +10,7 @@
 # Build up version_info tuple for backwards compatibility
 pattern = r"(?P<major>\d+).(?P<minor>\d+).(?P<patch>\d+)(?P<rest>.*)"
 match = re.match(pattern, __version__)
-assert match is not None
+assert match is not None  # noqa
 parts: List[object] = [int(match[part]) for part in ["major", "minor", "patch"]]
 if match["rest"]:
     parts.append(match["rest"])

jupyter_server_synchronizer/kernel_db.py

@@ -140,7 +140,7 @@ def row_to_record(self, row: sqlite3.Row) -> KernelRecord:
         items = {field: row[field] for field in self._table_columns}
         return self.kernel_record_class(**items)  # type:ignore[no-any-return]
 
-    def list(self) -> List[KernelRecord]:
+    def list(self) -> List[KernelRecord]:  # noqa
         self.cursor.execute(f"SELECT * FROM {self._table_name}")
         rows = self.cursor.fetchall()
         return [self.row_to_record(row) for row in rows]

jupyter_server_synchronizer/kernel_records.py

@@ -4,7 +4,7 @@
 from jupyter_client.manager import KernelManager
 
 
-class KernelRecordConflict(Exception):
+class KernelRecordConflict(Exception):  # noqa
     """An exception raised when trying to merge two
     kernels that have conflicting data.
     """
@@ -58,18 +58,18 @@ def get_identifier_fields(cls):
     def get_identifier_values(self):
         """The values of all identifiers."""
         identifier_values = []
-        for id in self.get_identifier_fields():
-            if id.endswith("_id"):
-                identifier_values.append(getattr(self, id))
+        for id_ in self.get_identifier_fields():
+            if id_.endswith("_id"):
+                identifier_values.append(getattr(self, id_))
         return identifier_values
 
     def get_active_identifiers(self):
         """Return a dictionary of all identifiers that are not None."""
         identifiers = {}
-        for id in self.get_identifier_fields():
-            val = getattr(self, id)
+        for id_ in self.get_identifier_fields():
+            val = getattr(self, id_)
             if val is not None:
-                identifiers[id] = val
+                identifiers[id_] = val
         return identifiers
 
     def get_active_fields(self):

jupyter_server_synchronizer/manager.py

@@ -1,10 +1,7 @@
 import asyncio
 import uuid
 
-from jupyter_server.services.sessions.sessionmanager import (
-    KernelSessionRecordList,
-    SessionManager,
-)
+from jupyter_server.services.sessions.sessionmanager import KernelSessionRecordList, SessionManager
 from traitlets import Bool, Float, Instance, Type, default
 
 from .gateway import fetch_gateway_kernels

pyproject.toml

@@ -47,6 +47,13 @@ test = [
   "pytest-jupyter[server]>=0.4.1",
   "pytest>=7.0",
 ]
+lint = [
+  "black[jupyter]>=22.6.0",
+  "mdformat>0.7",
+  "mdformat-gfm>=0.3.5",
+  "ruff>=0.0.156"
+]
+typing = ["mypy>=0.990"]
 
 [tool.hatch.version]
 path = "jupyter_server_synchronizer/_version.py"
@@ -65,6 +72,25 @@ dependencies = ["coverage", "pytest-cov"]
 test = "python -m pytest -vv --cov jupyter_server_synchronizer --cov-branch --cov-report term-missing:skip-covered {args}"
 nowarn = "test -W default {args}"
 
+[tool.hatch.envs.typing]
+features = ["typing", "test"]
+[tool.hatch.envs.typing.scripts]
+test = "mypy --install-types --non-interactive {args:jupyter_server_synchronizer tests}"
+
+[tool.hatch.envs.lint]
+features = ["lint"]
+[tool.hatch.envs.lint.scripts]
+style = [
+  "ruff {args:.}",
+  "black --check --diff {args:.}",
+  "mdformat --check {args:*.md}"
+]
+fmt = [
+  "black {args:.}",
+  "ruff --fix {args:.}",
+  "mdformat {args:*.md}"
+]
+
 [tool.jupyter-releaser.options]
 post-version-spec = "dev"
 
@@ -105,23 +131,29 @@ warn_redundant_casts = true
 warn_return_any = true
 warn_unused_ignores = true
 
-[tool.flake8]
-ignore = "E501, W503, E402"
-builtins = "c, get_config"
-exclude = [
-    ".cache",
-    ".github",
-    "docs",
-    "setup.py",
+[tool.black]
+line-length = 100
+skip-string-normalization = true
+target-version = ["py37"]
+
+[tool.ruff]
+target-version = "py37"
+line-length = 100
+select = [
+  "A", "B", "C", "E", "F", "FBT", "I", "N", "Q", "RUF", "S", "T",
+  "UP", "W", "YTT",
 ]
-enable-extensions = "G"
-extend-ignore = [
-    "G001", "G002", "G004", "G200", "G201", "G202",
-    # black adds spaces around ':'
-    "E203",
+ignore = [
+  # FBT002 Boolean default value in function definition
+  "FBT002", "FBT003",
 ]
-per-file-ignores = [
-    # B011: Do not call assert False since python -O removes these calls
-    # F841 local variable 'foo' is assigned to but never used
-    "tests/*: B011", "F841",
+unfixable = [
+  # Don't touch print statements
+  "T201",
+  # Don't touch noqa lines
+  "RUF100",
 ]
+
+[tool.ruff.per-file-ignores]
+# S101 Use of `assert` detected
+"tests/*" = ["S101"]

tests/test_kernel_db.py

@@ -11,7 +11,7 @@
 def test_database_is_created(jp_environ, jp_runtime_dir):
     path = jp_runtime_dir / "jupyter-session.db"
     table = KernelTable(database_filepath=str(path))
-    con = table.connection
+    _ = table.connection
     assert path.exists()