Enable ruff flake8-simplify rule

notes-to-self/file-read-latency.py

@@ -8,23 +8,22 @@
 # ns per call, instead of ~500 ns/call for the syscall and related overhead.
 # That's probably more fair -- the BufferedIOBase code can't service random
 # accesses, even if your working set fits entirely in RAM.
-f = open("/etc/passwd", "rb")  # , buffering=0)
+with open("/etc/passwd", "rb") as f:  # , buffering=0)
+    while True:
+        start = time.perf_counter()
+        for _ in range(COUNT):
+            f.seek(0)
+            f.read(1)
+        between = time.perf_counter()
+        for _ in range(COUNT):
+            f.seek(0)
+        end = time.perf_counter()
 
-while True:
-    start = time.perf_counter()
-    for _ in range(COUNT):
-        f.seek(0)
-        f.read(1)
-    between = time.perf_counter()
-    for _ in range(COUNT):
-        f.seek(0)
-    end = time.perf_counter()
-
-    both = (between - start) / COUNT * 1e9
-    seek = (end - between) / COUNT * 1e9
-    read = both - seek
-    print(
-        "{:.2f} ns/(seek+read), {:.2f} ns/seek, estimate ~{:.2f} ns/read".format(
-            both, seek, read
+        both = (between - start) / COUNT * 1e9
+        seek = (end - between) / COUNT * 1e9
+        read = both - seek
+        print(
+            "{:.2f} ns/(seek+read), {:.2f} ns/seek, estimate ~{:.2f} ns/read".format(
+                both, seek, read
+            )
         )
-    )

notes-to-self/proxy-benchmarks.py

@@ -156,24 +156,24 @@ def check(cls):
 for cls in classes:
     check(cls)
 
-f = open("/etc/passwd")
-objs = [c(f) for c in classes]
-
-COUNT = 1000000
-try:
-    import __pypy__  # noqa: F401  # __pypy__ imported but unused
-except ImportError:
-    pass
-else:
-    COUNT *= 10
-
-while True:
-    print("-------")
-    for obj in objs:
-        start = time.perf_counter()
-        for _ in range(COUNT):
-            obj.fileno()
-            # obj.fileno
-        end = time.perf_counter()
-        per_usec = COUNT / (end - start) / 1e6
-        print("{:7.2f} / us: {} ({})".format(per_usec, obj.strategy, obj.works_for))
+with open("/etc/passwd") as f:
+    objs = [c(f) for c in classes]
+
+    COUNT = 1000000
+    try:
+        import __pypy__  # noqa: F401  # __pypy__ imported but unused
+    except ImportError:
+        pass
+    else:
+        COUNT *= 10
+
+    while True:
+        print("-------")
+        for obj in objs:
+            start = time.perf_counter()
+            for _ in range(COUNT):
+                obj.fileno()
+                # obj.fileno
+            end = time.perf_counter()
+            per_usec = COUNT / (end - start) / 1e6
+            print("{:7.2f} / us: {} ({})".format(per_usec, obj.strategy, obj.works_for))

notes-to-self/trace.py

@@ -149,5 +149,6 @@ async def parent():
     print("parent: all done!")
 
 
-t = Trace(open("/tmp/t.json", "w"))
-trio.run(parent, instruments=[t])
+with open("/tmp/t.json", "w") as t_json:
+    t = Trace(t_json)
+    trio.run(parent, instruments=[t])

notes-to-self/win-waitable-timer.py

@@ -24,13 +24,14 @@
 # make this fairly straightforward, but you obviously need to use a separate
 # time source
 
+import contextlib
 from datetime import datetime, timedelta, timezone
 
 import cffi
 import trio
 from trio._core._windows_cffi import ffi, kernel32, raise_winerror
 
-try:
+with contextlib.suppress(cffi.CDefError):
     ffi.cdef(
         """
 typedef struct _PROCESS_LEAP_SECOND_INFO {
@@ -50,8 +51,6 @@
 } SYSTEMTIME, *PSYSTEMTIME, *LPSYSTEMTIME;
 """
     )
-except cffi.CDefError:
-    pass
 
 ffi.cdef(
     """

pyproject.toml

@@ -27,6 +27,7 @@ select = [
   "F",  # pyflakes
   "I",  # isort
   "YTT",  # flake8-2020
+  "SIM",  # flake8-simplify
 ]
 extend-ignore = [
     'F403',  # undefined-local-with-import-star

setup.py

@@ -2,7 +2,8 @@
 
 __version__ = "0.0.0"  # Overwritten from _version.py below, needed for linter to identify that this variable is defined.
 
-exec(open("trio/_version.py", encoding="utf-8").read())
+with open("trio/_version.py", encoding="utf-8") as version_code:
+    exec(version_code.read())
 
 LONG_DESC = """\
 .. image:: https://raw.githubusercontent.com/python-trio/trio/9b0bec646a31e0d0f67b8b6ecc6939726faf3e17/logo/logo-with-background.svg

trio/_core/_io_epoll.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import contextlib
 import select
 import sys
 from collections import defaultdict
@@ -324,7 +325,5 @@ def notify_closing(self, fd: int | _HasFileNo) -> None:
             _core.ClosedResourceError("another task closed this fd"),
         )
         del self._registered[fd]
-        try:
+        with contextlib.suppress(OSError, ValueError):
             self._epoll.unregister(fd)
-        except (OSError, ValueError):
-            pass

trio/_core/_multierror.py

@@ -328,7 +328,7 @@ def catch(
         return MultiErrorCatcher(handler)
 
 
-if TYPE_CHECKING:
+if TYPE_CHECKING:  # noqa: SIM108
     _ExceptionGroup = ExceptionGroup[Exception]
 else:
     _ExceptionGroup = ExceptionGroup
@@ -432,12 +432,15 @@ def controller(operation: tputil.ProxyOperation) -> Any | None:
             # 'opname' that isn't __getattr__ or __getattribute__. So there's
             # no missing test we could add, and no value in coverage nagging
             # us about adding one.
-            if operation.opname in [
-                "__getattribute__",
-                "__getattr__",
-            ]:  # pragma: no cover
-                if operation.args[0] == "tb_next":
-                    return tb_next
+            if (
+                operation.opname
+                in {
+                    "__getattribute__",
+                    "__getattr__",
+                }
+                and operation.args[0] == "tb_next"
+            ):  # pragma: no cover
+                return tb_next
             return operation.delegate()  # Deligate is reverting to original behaviour
 
         return cast(

trio/_core/_run.py

@@ -18,7 +18,7 @@
     Iterator,
     Sequence,
 )
-from contextlib import AbstractAsyncContextManager, contextmanager
+from contextlib import AbstractAsyncContextManager, contextmanager, suppress
 from contextvars import copy_context
 from heapq import heapify, heappop, heappush
 from math import inf
@@ -792,15 +792,19 @@ def cancel_called(self) -> bool:
         cancelled, then :attr:`cancelled_caught` is usually more
         appropriate.
         """
-        if self._cancel_status is not None or not self._has_been_entered:
+        if (
+            self._cancel_status is not None
+            or not self._has_been_entered
+            and not self._cancel_called
+            and current_time() >= self._deadline
+        ):
             # Scope is active or not yet entered: make sure cancel_called
             # is true if the deadline has passed. This shouldn't
             # be able to actually change behavior, since we check for
             # deadline expiry on scope entry and at every checkpoint,
             # but it makes the value returned by cancel_called more
             # closely match expectations.
-            if not self._cancel_called and current_time() >= self._deadline:
-                self.cancel()
+            self.cancel()
         return self._cancel_called
 
 
@@ -1705,10 +1709,7 @@ def spawn_impl(
         # Propagate contextvars
         ######
         if context is None:
-            if system_task:
-                context = self.system_context.copy()
-            else:
-                context = copy_context()
+            context = self.system_context.copy() if system_task else copy_context()
 
         ######
         # Call the function and get the coroutine object, while giving helpful
@@ -1940,10 +1941,8 @@ def current_trio_token(self) -> TrioToken:
     # This gets called from signal context
     def deliver_ki(self) -> None:
         self.ki_pending = True
-        try:
+        with suppress(RunFinishedError):
             self.entry_queue.run_sync_soon(self._deliver_ki_cb)
-        except RunFinishedError:
-            pass
 
     def _deliver_ki_cb(self) -> None:
         if not self.ki_pending:

trio/_core/_tests/test_asyncgen.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import contextlib
 import sys
 import weakref
 from collections.abc import AsyncGenerator
@@ -17,10 +18,8 @@ def test_asyncgen_basics() -> None:
 
     async def example(cause: str) -> AsyncGenerator[int, None]:
         try:
-            try:
+            with contextlib.suppress(GeneratorExit):
                 yield 42
-            except GeneratorExit:
-                pass
             await _core.checkpoint()
         except _core.Cancelled:
             assert "exhausted" not in cause
@@ -44,14 +43,14 @@ async def async_main() -> None:
         with pytest.warns(
             ResourceWarning, match="Async generator.*collected before.*exhausted"
         ):
-            assert 42 == await example("abandoned").asend(None)
+            assert await example("abandoned").asend(None) == 42
             gc_collect_harder()
         await _core.wait_all_tasks_blocked()
         assert collected.pop() == "abandoned"
 
         aiter = example("exhausted 1")
         try:
-            assert 42 == await aiter.asend(None)
+            assert await aiter.asend(None) == 42
         finally:
             await aiter.aclose()
         assert collected.pop() == "exhausted 1"
@@ -67,7 +66,7 @@ async def async_main() -> None:
         aiter = example("exhausted 3")
         try:
             saved.append(aiter)
-            assert 42 == await aiter.asend(None)
+            assert await aiter.asend(None) == 42
         finally:
             await aiter.aclose()
         assert collected.pop() == "exhausted 3"
@@ -83,7 +82,7 @@ async def async_main() -> None:
             collected.append("outlived run")
         else:
             saved.append(example("outlived run"))
-            assert 42 == await saved[-1].asend(None)
+            assert await saved[-1].asend(None) == 42
             assert collected == []
 
     _core.run(async_main)
@@ -137,8 +136,8 @@ async def funky_agen() -> AsyncGenerator[int, None]:
     async def async_main() -> None:
         aiter = funky_agen()
         saved.append(aiter)
-        assert 1 == await aiter.asend(None)
-        assert 2 == await aiter.asend(None)
+        assert await aiter.asend(None) == 1
+        assert await aiter.asend(None) == 2
 
     _core.run(async_main)
     assert record == ["cleanup 2", "cleanup 1"]
@@ -178,7 +177,7 @@ async def async_main() -> None:
         for idx in range(100):
             ag_chain = agen(idx, ag_chain)
         saved.append(ag_chain)
-        assert 1 == await ag_chain.asend(None)
+        assert await ag_chain.asend(None) == 1
         assert record == []
 
     _core.run(async_main)
@@ -320,7 +319,7 @@ async def example(arg: str) -> AsyncGenerator[int, None]:
 
     async def async_main() -> None:
         await step_outside_async_context(example("theirs"))
-        assert 42 == await example("ours").asend(None)
+        assert await example("ours").asend(None) == 42
         gc_collect_harder()
         assert record == ["firstiter theirs", "finalizer theirs"]
         record[:] = []

trio/_core/_tests/test_guest_mode.py

@@ -1,4 +1,5 @@
 import asyncio
+import contextlib
 import contextvars
 import queue
 import signal
@@ -593,10 +594,8 @@ async def agen(label):
             yield 1
         finally:
             library = sniffio.current_async_library()
-            try:
+            with contextlib.suppress(trio.Cancelled):
                 await sys.modules[library].sleep(0)
-            except trio.Cancelled:
-                pass
             record.add((label, library))
 
     async def iterate_in_aio():

trio/_core/_tests/test_ki.py

@@ -138,7 +138,7 @@ def protected_manager():
     with protected_manager():
         assert not _core.currently_ki_protected()
 
-    with pytest.raises(KeyError):
+    with pytest.raises(KeyError):  # noqa: SIM117  # multiple-with-statements
         # This is the one that used to fail
         with protected_manager():
             raise KeyError