various: turn on more ruff rules, fix things up

Copy over the ruff config from Cockpit, more or less, with some slight
tweaks.  Fix up the things that got picked up.

The biggest change is that we can't reasonably use any of the FBT rules
here because systemd has booleans on several of its APIs and the binding
layer only supports positional parameters.

pyproject.toml

@@ -22,6 +22,42 @@ log_cli = true
 
 [tool.ruff]
 line-length = 118
+select = [
+    "A",       # flake8-builtins
+    "B",       # flake8-bugbear
+    "C4",      # flake8-comprehensions
+    "D300",    # pydocstyle: Forbid ''' in docstrings
+    "DTZ",     # flake8-datetimez
+    "E",       # pycodestyle
+    "EXE",     # flake8-executable
+    "F",       # pyflakes
+    "G",       # flake8-logging-format
+    "I",       # isort
+    "ICN",     # flake8-import-conventions
+    "ISC",     # flake8-implicit-str-concat
+    "PLE",     # pylint errors
+    "PGH",     # pygrep-hooks
+    "PT",      # flake8-pytest-style
+    "RSE",     # flake8-raise
+    "RUF",     # ruff rules
+    "T10",     # flake8-debugger
+    "TCH",     # flake8-type-checking
+    "W",       # warnings (mostly whitespace)
+    "YTT",     # flake8-2020
+]
+ignore = [
+    "A003",    # Class attribute is shadowing a python builtin
+    "B905",    # `zip()` without an explicit `strict=` parameter
+    "PT009",   # Use a regular `assert` instead of unittest-style `assertEqual`
+    "PT017",   # Found assertion on exception `exc` in `except` block, use `pytest.raises()` instead
+]
+
+[tool.ruff.flake8-pytest-style]
+fixture-parentheses = false
+mark-parentheses = false
+
+[tool.ruff.isort]
+known-first-party = ["systemd_ctypes"]
 
 [tool.coverage.paths]
 source = ["src", "*/site-packages"]

src/systemd_ctypes/__init__.py

@@ -20,9 +20,9 @@
 __version__ = "0"
 
 from .bus import Bus, BusError, BusMessage
+from .bustypes import BusType, JSONEncoder, Variant
 from .event import Event, EventLoopPolicy, run_async
 from .pathwatch import Handle, PathWatch
-from .bustypes import BusType, JSONEncoder, Variant
 
 __all__ = [
     "Bus",

src/systemd_ctypes/bus.py

@@ -442,7 +442,8 @@ def emit_signal(
         :args: the arguments, according to the signature
         :returns: True
         """
-        assert self._dbus_bus is not None and self._dbus_path is not None
+        assert self._dbus_bus is not None
+        assert self._dbus_path is not None
         return self._dbus_bus.message_new_signal(self._dbus_path, interface, name, signature, *args).send()
 
     def message_received(self, message: BusMessage) -> bool:

src/systemd_ctypes/bustypes.py

@@ -347,10 +347,10 @@ def dict_reader(message: libsystemd.sd_bus_message) -> object:
     def get_writer(self, a, item_type, e, type_contents, open_container, close_container, key_writer, value_writer):
         def dict_writer(message: libsystemd.sd_bus_message, value: object) -> None:
             open_container(message, a, item_type)                    # array
-            for key, value in value.items():  # type: ignore[attr-defined] # can raise AttributeError
+            for key, val in value.items():  # type: ignore[attr-defined] # can raise AttributeError
                 open_container(message, e, type_contents)              # entry
                 key_writer(message, key)                                 # key
-                value_writer(message, value)                             # value
+                value_writer(message, val)                               # value
                 close_container(message)                               # end entry
             close_container(message)                                 # end array
         return dict_writer
@@ -475,7 +475,7 @@ def from_annotation(annotation: Union[str, type, BusType]) -> Type:
         args = [from_annotation(arg) for arg in typing.get_args(annotation)]
         return factory(*args)
     except (AssertionError, AttributeError, KeyError, TypeError):
-        raise TypeError(f"Cannot interpret {annotation} as a dbus type")
+        raise TypeError(f"Cannot interpret {annotation} as a dbus type") from None
 
 
 _base_typestring_map: Dict[str, Type] = {

src/systemd_ctypes/event.py

@@ -20,11 +20,9 @@
 import sys
 from typing import Callable, ClassVar, Coroutine, List, Optional, Tuple
 
+from . import inotify, libsystemd
 from .librarywrapper import Callback, Reference, UserData, byref
 
-from . import inotify
-from . import libsystemd
-
 
 class Event(libsystemd.sd_event):
     class Source(libsystemd.sd_event_source):

src/systemd_ctypes/inotify.py

@@ -21,20 +21,20 @@
 
 
 class inotify_event(ctypes.Structure):
-    _fields_ = [
+    _fields_ = (
         ('wd', ctypes.c_int32),
         ('mask', ctypes.c_uint32),
         ('cookie', ctypes.c_uint32),
         ('len', ctypes.c_uint32),
-    ]
+    )
 
     @property
     def name(self) -> Optional[bytes]:
         if self.len == 0:
             return None
 
         class event_with_name(ctypes.Structure):
-            _fields_ = [*inotify_event._fields_, ('name', ctypes.c_char * self.len)]
+            _fields_ = (*inotify_event._fields_, ('name', ctypes.c_char * self.len))
 
         name = ctypes.cast(ctypes.addressof(self), ctypes.POINTER(event_with_name)).contents.name
         assert isinstance(name, bytes)

src/systemd_ctypes/introspection.py

@@ -56,7 +56,7 @@ def element(tag, children=(), **kwargs):
     return tag
 
 
-def method(name, method_info):
+def method_to_xml(name, method_info):
     return element('method', name=name,
                    children=[
                        element('arg', type=arg_type, direction=direction)
@@ -65,28 +65,28 @@ def method(name, method_info):
                    ])
 
 
-def property(name, property_info):
+def property_to_xml(name, property_info):
     return element('property', name=name,
                    access='write' if property_info['flags'] == 'w' else 'read',
                    type=property_info['type'])
 
 
-def signal(name, signal_info):
+def signal_to_xml(name, signal_info):
     return element('signal', name=name,
                    children=[
                        element('arg', type=arg_type) for arg_type in signal_info['in']
                    ])
 
 
-def interface(name, interface_info):
+def interface_to_xml(name, interface_info):
     return element('interface', name=name,
                    children=[
-                       *(method(name, info) for name, info in interface_info['methods'].items()),
-                       *(property(name, info) for name, info in interface_info['properties'].items()),
-                       *(signal(name, info) for name, info in interface_info['signals'].items()),
+                       *(method_to_xml(name, info) for name, info in interface_info['methods'].items()),
+                       *(property_to_xml(name, info) for name, info in interface_info['properties'].items()),
+                       *(signal_to_xml(name, info) for name, info in interface_info['signals'].items()),
                    ])
 
 
 def to_xml(interfaces):
-    node = element('node', children=(interface(name, members) for name, members in interfaces.items()))
+    node = element('node', children=(interface_to_xml(name, members) for name, members in interfaces.items()))
     return ET.tostring(node, encoding='unicode')

test/test_basic.py

@@ -15,15 +15,14 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import json
 import tempfile
 import unittest
 
 import dbusmock  # type: ignore[import] # not typed
-import json
 
 import systemd_ctypes
-from systemd_ctypes import introspection, bus
-
+from systemd_ctypes import bus, introspection
 
 TEST_ADDR = ('org.freedesktop.Test', '/', 'org.freedesktop.Test.Main')
 

test/test_bustypes.py

@@ -5,6 +5,7 @@
 from typing import List
 
 import pytest
+
 from systemd_ctypes import Bus, BusMessage, BusType, bustypes
 
 
@@ -18,7 +19,7 @@ def message(bus):
     return bus.message_new_method_call('x.y', '/y', 'z.a', 'a')
 
 
-@pytest.mark.parametrize('annotation,typestring', [
+@pytest.mark.parametrize(('annotation', 'typestring'), [
     (BusType.boolean, 'b'),
     (BusType.byte, 'y'),
     (BusType.int16, 'n'),
@@ -97,34 +98,34 @@ def test_simple(message: BusMessage) -> None:
 def test_bad_path(message: BusMessage) -> None:
     writer = bustypes.from_annotation(BusType.objectpath).writer
     writer(message, '/path')
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match="Invalid value provided for type 'o'"):
         writer(message, 'path')
 
 
 def test_bad_signature(message: BusMessage) -> None:
     writer = bustypes.from_annotation(BusType.signature).writer
     writer(message, 'a{sv}')
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match="Invalid value provided for type 'g'"):
         writer(message, 'a{vs}')
 
 
 def test_bad_base64(message: BusMessage) -> None:
     writer = bustypes.from_annotation(BusType.bytestring).writer
     writer(message, '')
     writer(message, 'aaaa')
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match="invalid base64"):
         writer(message, 'a')
 
 
 def test_bad_mapping(message: BusMessage) -> None:
     writer = bustypes.from_annotation(typing.Dict[str, str]).writer
     writer(message, {})
     writer(message, {'a': 'b', 'c': 'd'})
-    with pytest.raises(AttributeError):
+    with pytest.raises(AttributeError, match="'set'.*'items'"):
         writer(message, {'a', 'b', 'c'})  # no '.items()'
-    with pytest.raises(TypeError):
+    with pytest.raises(TypeError, match="'str'.*'int'"):
         writer(message, {1: 'a'})  # wrong key type
-    with pytest.raises(TypeError):
+    with pytest.raises(TypeError, match="'str'.*'int'"):
         writer(message, {'a': 1})  # wrong value type
 
     class weird:
@@ -137,9 +138,9 @@ def items(self):
     writer(message, weird([]))
     with pytest.raises(TypeError):
         writer(message, weird([1]))            # can't unpack '1' as key, value -- wrong type
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match="not enough values to unpack"):
         writer(message, weird([()]))           # can't unpack () as key, value -- wrong value
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match="too many values to unpack"):
         writer(message, weird([(1, 2, 3)]))    # ditto
 
 
@@ -154,7 +155,7 @@ def test_bytestring(message: BusMessage) -> None:
 one_third = Fraction(1, 3)
 
 
-@pytest.mark.parametrize('typestring,value', [
+@pytest.mark.parametrize(('typestring', 'value'), [
     ('y', 0), ('y', 255),
     ('n', -2**15), ('n', 2**15 - 1), ('q', 0), ('q', 2**16 - 1),
     ('i', -2**31), ('i', 2**31 - 1), ('u', 0), ('u', 2**32 - 1),
@@ -168,7 +169,7 @@ def test_number_limits(message: BusMessage, typestring: str, value: object) -> N
     assert x == value
 
 
-@pytest.mark.parametrize('typestring,value', [
+@pytest.mark.parametrize(('typestring', 'value'), [
     ('y', 256), ('y', -1), ('y', one_half),
     ('n', -2**15 - 1), ('n', 2**15), ('n', one_half), ('q', -1), ('q', 2**16), ('q', one_half),
     ('i', -2**31 - 1), ('i', 2**31), ('i', one_half), ('u', -1), ('u', 2**32), ('u', one_half),

test/test_p2p.py

@@ -1,10 +1,11 @@
 import asyncio
 import socket
-import pytest
 import unittest
 from tempfile import TemporaryDirectory
 
-from systemd_ctypes import bus, introspection, run_async, BusError
+import pytest
+
+from systemd_ctypes import BusError, bus, introspection, run_async
 
 
 class CommonTests:

test/test_pathwatch.py

@@ -20,13 +20,11 @@
 import os
 import tempfile
 import unittest
-
 from unittest.mock import MagicMock
 
 import systemd_ctypes
 from systemd_ctypes.inotify import Event
 
-
 with open("/etc/os-release") as f:
     os_release = f.read()
 
@@ -38,7 +36,7 @@ def setUp(self):
 
     def async_wait_cond(self, cond):
         async def _call():
-            for retry in range(50):
+            for _ in range(50):
                 if cond():
                     break
                 await asyncio.sleep(0.1)

test/test_refloop.py

@@ -1,9 +1,9 @@
 import errno
 import gc
 import os
+import socket
 import unittest
 
-import socket
 from systemd_ctypes import bus