From 61fb33021e0aa207680a46f56a24584436d83362 Mon Sep 17 00:00:00 2001
From: CoolCat467 <52022020+CoolCat467@users.noreply.github.com>
Date: Mon, 14 Aug 2023 13:25:38 -0500
Subject: [PATCH 01/15] Add typing for `_wait_for_object.py`

---
 trio/_core/_windows_cffi.py | 21 ++++++++++++++++-----
 trio/_wait_for_object.py    | 13 ++++++++++---
 2 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/trio/_core/_windows_cffi.py b/trio/_core/_windows_cffi.py
index 639e75b50e..37bed14c50 100644
--- a/trio/_core/_windows_cffi.py
+++ b/trio/_core/_windows_cffi.py
@@ -1,7 +1,14 @@
+from __future__ import annotations
+
 import enum
 import re
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from typing_extensions import NoReturn
 
 import cffi
+from cffi.FFI import CData as CData
 
 ################################################################
 # Functions and types
@@ -302,20 +309,24 @@ class IoControlCodes(enum.IntEnum):
 ################################################################
 
 
-def _handle(obj):
+def _handle(obj: int | CData) -> CData:
     # For now, represent handles as either cffi HANDLEs or as ints.  If you
     # try to pass in a file descriptor instead, it's not going to work
     # out. (For that msvcrt.get_osfhandle does the trick, but I don't know if
     # we'll actually need that for anything...) For sockets this doesn't
     # matter, Python never allocates an fd. So let's wait until we actually
     # encounter the problem before worrying about it.
-    if type(obj) is int:
+    if isinstance(obj, int):
         return ffi.cast("HANDLE", obj)
-    else:
-        return obj
+    return obj
 
 
-def raise_winerror(winerror=None, *, filename=None, filename2=None):
+def raise_winerror(
+    winerror: int | None = None,
+    *,
+    filename: str | None = None,
+    filename2: str | None = None,
+) -> NoReturn:
     if winerror is None:
         winerror, msg = ffi.getwinerror()
     else:
diff --git a/trio/_wait_for_object.py b/trio/_wait_for_object.py
index 32a88e5398..254d07561c 100644
--- a/trio/_wait_for_object.py
+++ b/trio/_wait_for_object.py
@@ -2,10 +2,17 @@
 
 import trio
 
-from ._core._windows_cffi import ErrorCodes, _handle, ffi, kernel32, raise_winerror
+from ._core._windows_cffi import (
+    CData,
+    ErrorCodes,
+    _handle,
+    ffi,
+    kernel32,
+    raise_winerror,
+)
 
 
-async def WaitForSingleObject(obj):
+async def WaitForSingleObject(obj: int | CData) -> None:
     """Async and cancellable variant of WaitForSingleObject. Windows only.
 
     Args:
@@ -45,7 +52,7 @@ async def WaitForSingleObject(obj):
         kernel32.CloseHandle(cancel_handle)
 
 
-def WaitForMultipleObjects_sync(*handles):
+def WaitForMultipleObjects_sync(*handles: int | CData) -> None:
     """Wait for any of the given Windows handles to be signaled."""
     n = len(handles)
     handle_arr = ffi.new(f"HANDLE[{n}]")

From 9ff1bed38174ad7fa625578310e3dffbc87b2412 Mon Sep 17 00:00:00 2001
From: CoolCat467 <52022020+CoolCat467@users.noreply.github.com>
Date: Mon, 14 Aug 2023 13:33:14 -0500
Subject: [PATCH 02/15] Fix CData type

---
 trio/_core/_windows_cffi.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/trio/_core/_windows_cffi.py b/trio/_core/_windows_cffi.py
index 37bed14c50..7649bf920f 100644
--- a/trio/_core/_windows_cffi.py
+++ b/trio/_core/_windows_cffi.py
@@ -8,7 +8,6 @@
     from typing_extensions import NoReturn
 
 import cffi
-from cffi.FFI import CData as CData
 
 ################################################################
 # Functions and types
@@ -223,6 +222,7 @@
 LIB = re.sub(r"\bPASCAL\b", "__stdcall", LIB)
 
 ffi = cffi.FFI()
+CData = ffi.CData
 ffi.cdef(LIB)
 
 kernel32 = ffi.dlopen("kernel32.dll")

From 4e8a2c20ec52ecca233c432eb9842f6eb87df85d Mon Sep 17 00:00:00 2001
From: CoolCat467 <52022020+CoolCat467@users.noreply.github.com>
Date: Mon, 14 Aug 2023 20:06:55 -0500
Subject: [PATCH 03/15] Future annotations

---
 trio/_wait_for_object.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/trio/_wait_for_object.py b/trio/_wait_for_object.py
index 254d07561c..50a9d13ff2 100644
--- a/trio/_wait_for_object.py
+++ b/trio/_wait_for_object.py
@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import math
 
 import trio

From f119f027fa1de120fb41a798d84a3e6802de37e1 Mon Sep 17 00:00:00 2001
From: CoolCat467 <52022020+CoolCat467@users.noreply.github.com>
Date: Mon, 14 Aug 2023 20:13:30 -0500
Subject: [PATCH 04/15] Use explicit type alias

---
 trio/_core/_windows_cffi.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/trio/_core/_windows_cffi.py b/trio/_core/_windows_cffi.py
index 7649bf920f..152d7941d4 100644
--- a/trio/_core/_windows_cffi.py
+++ b/trio/_core/_windows_cffi.py
@@ -5,7 +5,7 @@
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
-    from typing_extensions import NoReturn
+    from typing_extensions import NoReturn, TypeAlias
 
 import cffi
 
@@ -222,7 +222,7 @@
 LIB = re.sub(r"\bPASCAL\b", "__stdcall", LIB)
 
 ffi = cffi.FFI()
-CData = ffi.CData
+CData: TypeAlias = ffi.CData
 ffi.cdef(LIB)
 
 kernel32 = ffi.dlopen("kernel32.dll")

From fe151df09b171645c05cb6ed1e4de150da0a28a7 Mon Sep 17 00:00:00 2001
From: CoolCat467 <52022020+CoolCat467@users.noreply.github.com>
Date: Mon, 14 Aug 2023 22:14:53 -0500
Subject: [PATCH 05/15] Maybe saying it's `cffi.api.FFI` will fix it?

---
 trio/_core/_windows_cffi.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/trio/_core/_windows_cffi.py b/trio/_core/_windows_cffi.py
index 152d7941d4..bab7d4ada5 100644
--- a/trio/_core/_windows_cffi.py
+++ b/trio/_core/_windows_cffi.py
@@ -221,7 +221,7 @@
 #   being _MSC_VER >= 800)
 LIB = re.sub(r"\bPASCAL\b", "__stdcall", LIB)
 
-ffi = cffi.FFI()
+ffi = cffi.api.FFI()
 CData: TypeAlias = ffi.CData
 ffi.cdef(LIB)
 

From 0ea0464087c8af2fa78fda550f8758eca49cdc9e Mon Sep 17 00:00:00 2001
From: Spencer Brown <spencerb21@live.com>
Date: Tue, 15 Aug 2023 17:33:52 +1000
Subject: [PATCH 06/15] Fix this type alias

---
 trio/_core/_windows_cffi.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/trio/_core/_windows_cffi.py b/trio/_core/_windows_cffi.py
index bab7d4ada5..a042dfae9f 100644
--- a/trio/_core/_windows_cffi.py
+++ b/trio/_core/_windows_cffi.py
@@ -222,7 +222,7 @@
 LIB = re.sub(r"\bPASCAL\b", "__stdcall", LIB)
 
 ffi = cffi.api.FFI()
-CData: TypeAlias = ffi.CData
+CData: TypeAlias = cffi.api.FFI.CData
 ffi.cdef(LIB)
 
 kernel32 = ffi.dlopen("kernel32.dll")

From d8f5306ae30b177c12ebfef736db6c0118a2aeae Mon Sep 17 00:00:00 2001
From: Spencer Brown <spencerb21@live.com>
Date: Thu, 17 Aug 2023 18:28:34 +1000
Subject: [PATCH 07/15] Handle None in raise_winerror()

---
 trio/_core/_windows_cffi.py | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/trio/_core/_windows_cffi.py b/trio/_core/_windows_cffi.py
index a042dfae9f..596284025b 100644
--- a/trio/_core/_windows_cffi.py
+++ b/trio/_core/_windows_cffi.py
@@ -328,8 +328,14 @@ def raise_winerror(
     filename2: str | None = None,
 ) -> NoReturn:
     if winerror is None:
-        winerror, msg = ffi.getwinerror()
+        err = ffi.getwinerror()
+        if err is None:
+            raise OSError("No error set?")
+        winerror, msg = err
     else:
-        _, msg = ffi.getwinerror(winerror)
+        err = ffi.getwinerror()
+        if err is None:
+            raise OSError("No error set?")
+        _, msg = err
     # https://docs.python.org/3/library/exceptions.html#OSError
     raise OSError(0, msg, filename, winerror, filename2)

From fd26a24512c3ab5b846172cea887b1f837c0a8ef Mon Sep 17 00:00:00 2001
From: Spencer Brown <spencerb21@live.com>
Date: Thu, 17 Aug 2023 20:34:43 +1000
Subject: [PATCH 08/15] Fix copy-paste error

Interestingly not caught by tests, maybe we need specific tests for this.
---
 trio/_core/_windows_cffi.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/trio/_core/_windows_cffi.py b/trio/_core/_windows_cffi.py
index 596284025b..973eaeb912 100644
--- a/trio/_core/_windows_cffi.py
+++ b/trio/_core/_windows_cffi.py
@@ -333,7 +333,7 @@ def raise_winerror(
             raise OSError("No error set?")
         winerror, msg = err
     else:
-        err = ffi.getwinerror()
+        err = ffi.getwinerror(winerror)
         if err is None:
             raise OSError("No error set?")
         _, msg = err

From b9aa4d1e709f5ee76bd7b95cebcc8beff02a6af2 Mon Sep 17 00:00:00 2001
From: CoolCat467 <52022020+CoolCat467@users.noreply.github.com>
Date: Thu, 17 Aug 2023 19:21:16 -0500
Subject: [PATCH 09/15] Update `pyproject.toml`

---
 pyproject.toml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/pyproject.toml b/pyproject.toml
index 073e2508d1..d272f0d6f6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -62,7 +62,7 @@ module = [
     "trio._core._thread_cache",
     "trio._core._traps",
     "trio._core._unbounded_queue",
-    "trio._core._unbounded_queue",
+    "trio._core._windows_cffi",
     "trio._deprecate",
     "trio._dtls",
     "trio._file_io",
@@ -78,6 +78,7 @@ module = [
     "trio._threads",
     "trio._tools.gen_exports",
     "trio._util",
+    "trio._wait_for_object",
 ]
 disallow_incomplete_defs = true
 disallow_untyped_defs = true

From 5748203bce3fe12edbcfb4c7e810aa4955921d36 Mon Sep 17 00:00:00 2001
From: Spencer Brown <spencerb21@live.com>
Date: Fri, 18 Aug 2023 13:19:17 +1000
Subject: [PATCH 10/15] Add a test for raise_winerror()

---
 trio/_core/_tests/test_windows.py | 38 +++++++++++++++++++++++++++++++
 trio/_core/_windows_cffi.py       |  4 ++--
 2 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/trio/_core/_tests/test_windows.py b/trio/_core/_tests/test_windows.py
index 0dac94543c..6f40be1b24 100644
--- a/trio/_core/_tests/test_windows.py
+++ b/trio/_core/_tests/test_windows.py
@@ -1,6 +1,7 @@
 import os
 import tempfile
 from contextlib import contextmanager
+from unittest.mock import create_autospec
 
 import pytest
 
@@ -22,6 +23,43 @@
     )
 
 
+def test_winerror(monkeypatch) -> None:
+    mock = create_autospec(ffi.getwinerror)
+    monkeypatch.setattr(ffi, "getwinerror", mock)
+
+    # Returning none = no error, should not happen.
+    mock.return_value = None
+    with pytest.raises(RuntimeError, match="No error set"):
+        raise_winerror()
+    mock.assert_called_once_with()
+    mock.reset_mock()
+
+    with pytest.raises(RuntimeError, match="No error set"):
+        raise_winerror(38)
+    mock.assert_called_once_with(38)
+    mock.reset_mock()
+
+    mock.return_value = (12, "test error")
+    with pytest.raises(OSError) as exc:
+        raise_winerror(filename="file_1", filename2="file_2")
+    mock.assert_called_once_with()
+    mock.reset_mock()
+    assert exc.value.winerror == 12
+    assert exc.value.strerror == "test error"
+    assert exc.value.filename == "file_1"
+    assert exc.value.filename2 == "file_2"
+
+    # With an explicit number passed in, it overrides what getwinerror() returns.
+    with pytest.raises(OSError) as exc:
+        raise_winerror(18, filename="afile", filename2="bfile")
+    mock.assert_called_once_with(18)
+    mock.reset_mock()
+    assert exc.value.winerror == 18
+    assert exc.value.strerror == "test error"
+    assert exc.value.filename == "afile"
+    assert exc.value.filename2 == "bfile"
+
+
 # The undocumented API that this is testing should be changed to stop using
 # UnboundedQueue (or just removed until we have time to redo it), but until
 # then we filter out the warning.
diff --git a/trio/_core/_windows_cffi.py b/trio/_core/_windows_cffi.py
index 973eaeb912..a65a332c2f 100644
--- a/trio/_core/_windows_cffi.py
+++ b/trio/_core/_windows_cffi.py
@@ -330,12 +330,12 @@ def raise_winerror(
     if winerror is None:
         err = ffi.getwinerror()
         if err is None:
-            raise OSError("No error set?")
+            raise RuntimeError("No error set?")
         winerror, msg = err
     else:
         err = ffi.getwinerror(winerror)
         if err is None:
-            raise OSError("No error set?")
+            raise RuntimeError("No error set?")
         _, msg = err
     # https://docs.python.org/3/library/exceptions.html#OSError
     raise OSError(0, msg, filename, winerror, filename2)

From 8d46654f32cd360d4b7863d78a96877333fdee6f Mon Sep 17 00:00:00 2001
From: Spencer Brown <spencerb21@live.com>
Date: Fri, 18 Aug 2023 13:22:44 +1000
Subject: [PATCH 11/15] Change names

---
 trio/_core/_tests/test_windows.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/trio/_core/_tests/test_windows.py b/trio/_core/_tests/test_windows.py
index 6f40be1b24..69b95b15ce 100644
--- a/trio/_core/_tests/test_windows.py
+++ b/trio/_core/_tests/test_windows.py
@@ -51,13 +51,13 @@ def test_winerror(monkeypatch) -> None:
 
     # With an explicit number passed in, it overrides what getwinerror() returns.
     with pytest.raises(OSError) as exc:
-        raise_winerror(18, filename="afile", filename2="bfile")
+        raise_winerror(18, filename="a/file", filename2="b/file")
     mock.assert_called_once_with(18)
     mock.reset_mock()
     assert exc.value.winerror == 18
     assert exc.value.strerror == "test error"
-    assert exc.value.filename == "afile"
-    assert exc.value.filename2 == "bfile"
+    assert exc.value.filename == "a/file"
+    assert exc.value.filename2 == "b/file"
 
 
 # The undocumented API that this is testing should be changed to stop using

From 31c038fe8773b5e46095b751a3ef66b799d6a2b8 Mon Sep 17 00:00:00 2001
From: CoolCat467 <52022020+CoolCat467@users.noreply.github.com>
Date: Fri, 18 Aug 2023 21:49:33 -0500
Subject: [PATCH 12/15] Fix mypy CI failure on linux and macos

---
 trio/_core/_tests/test_windows.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/trio/_core/_tests/test_windows.py b/trio/_core/_tests/test_windows.py
index 69b95b15ce..d2231cc8a8 100644
--- a/trio/_core/_tests/test_windows.py
+++ b/trio/_core/_tests/test_windows.py
@@ -44,7 +44,8 @@ def test_winerror(monkeypatch) -> None:
         raise_winerror(filename="file_1", filename2="file_2")
     mock.assert_called_once_with()
     mock.reset_mock()
-    assert exc.value.winerror == 12
+    if sys.platform == "win32":  # mypy complains otherwise
+        assert exc.value.winerror == 12
     assert exc.value.strerror == "test error"
     assert exc.value.filename == "file_1"
     assert exc.value.filename2 == "file_2"
@@ -54,7 +55,8 @@ def test_winerror(monkeypatch) -> None:
         raise_winerror(18, filename="a/file", filename2="b/file")
     mock.assert_called_once_with(18)
     mock.reset_mock()
-    assert exc.value.winerror == 18
+    if sys.platform == "win32":  # mypy complains otherwise
+        assert exc.value.winerror == 18
     assert exc.value.strerror == "test error"
     assert exc.value.filename == "a/file"
     assert exc.value.filename2 == "b/file"

From 3e9c132a6b3202f0e42405f1320cecbabbd21644 Mon Sep 17 00:00:00 2001
From: CoolCat467 <52022020+CoolCat467@users.noreply.github.com>
Date: Fri, 18 Aug 2023 21:50:59 -0500
Subject: [PATCH 13/15] Remove `_wait_for_object` and `_core._windows_cffi`
 fully typed ignores

---
 pyproject.toml | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/pyproject.toml b/pyproject.toml
index 9a505b2674..98917df4c1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -62,9 +62,6 @@ module = [
 "trio/_highlevel_serve_listeners",
 "trio/_highlevel_ssl_helpers",
 "trio/_highlevel_socket",
-# 2755
-"trio/_core/_windows_cffi",
-"trio/_wait_for_object",
 # 2761
 "trio/_core/_generated_io_windows",
 "trio/_core/_io_windows",

From 5d3f5583200110ec402894fa2f53bfb30a69a0c0 Mon Sep 17 00:00:00 2001
From: CoolCat467 <52022020+CoolCat467@users.noreply.github.com>
Date: Fri, 18 Aug 2023 23:36:00 -0500
Subject: [PATCH 14/15] Import sys for new mypy CI fix

---
 trio/_core/_tests/test_windows.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/trio/_core/_tests/test_windows.py b/trio/_core/_tests/test_windows.py
index d2231cc8a8..4732cd95c3 100644
--- a/trio/_core/_tests/test_windows.py
+++ b/trio/_core/_tests/test_windows.py
@@ -1,4 +1,5 @@
 import os
+import sys
 import tempfile
 from contextlib import contextmanager
 from unittest.mock import create_autospec

From b268935152dcf8a0a36fe93b8d7ff64fcf397713 Mon Sep 17 00:00:00 2001
From: Spencer Brown <spencerb21@live.com>
Date: Sat, 19 Aug 2023 16:43:39 +1000
Subject: [PATCH 15/15] Entirely skip type checking test_windows on other
 platforms

---
 trio/_core/_tests/test_windows.py | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/trio/_core/_tests/test_windows.py b/trio/_core/_tests/test_windows.py
index 4732cd95c3..99bb97284b 100644
--- a/trio/_core/_tests/test_windows.py
+++ b/trio/_core/_tests/test_windows.py
@@ -2,6 +2,7 @@
 import sys
 import tempfile
 from contextlib import contextmanager
+from typing import TYPE_CHECKING
 from unittest.mock import create_autospec
 
 import pytest
@@ -10,6 +11,8 @@
 # Mark all the tests in this file as being windows-only
 pytestmark = pytest.mark.skipif(not on_windows, reason="windows only")
 
+assert sys.platform == "win32" or not TYPE_CHECKING  # Skip type checking on Windows
+
 from ... import _core, sleep
 from ...testing import wait_all_tasks_blocked
 from .tutil import gc_collect_harder, restore_unraisablehook, slow
@@ -45,8 +48,7 @@ def test_winerror(monkeypatch) -> None:
         raise_winerror(filename="file_1", filename2="file_2")
     mock.assert_called_once_with()
     mock.reset_mock()
-    if sys.platform == "win32":  # mypy complains otherwise
-        assert exc.value.winerror == 12
+    assert exc.value.winerror == 12
     assert exc.value.strerror == "test error"
     assert exc.value.filename == "file_1"
     assert exc.value.filename2 == "file_2"
@@ -56,8 +58,7 @@ def test_winerror(monkeypatch) -> None:
         raise_winerror(18, filename="a/file", filename2="b/file")
     mock.assert_called_once_with(18)
     mock.reset_mock()
-    if sys.platform == "win32":  # mypy complains otherwise
-        assert exc.value.winerror == 18
+    assert exc.value.winerror == 18
     assert exc.value.strerror == "test error"
     assert exc.value.filename == "a/file"
     assert exc.value.filename2 == "b/file"