python: Annotate context managers as returning Generator

bin/tine.py

@@ -13,7 +13,7 @@
 import signal
 import sys
 import tomllib
-from collections.abc import Iterator, Mapping
+from collections.abc import Generator, Mapping
 from contextlib import ExitStack, contextmanager
 from dataclasses import dataclass
 from pathlib import Path
@@ -1423,7 +1423,7 @@ def refresh_project_buckconfig(root: Path, overrides: dict[str, dict[str, str]])
 
 
 @contextmanager
-def mount_table_lock(root: Path) -> Iterator[None]:
+def mount_table_lock(root: Path) -> Generator[None]:
     """Keep concurrent mount-table edits from losing each other's changes."""
     path = root / MOUNT_LOCK
     try:

bin/tine_test.py

@@ -974,7 +974,7 @@ def test_the_mount_file_rejects_unrelated_local_settings(self) -> None:
 
 class TestMountUpdates(MountTestCase):
     @contextlib.contextmanager
-    def process(self, code: str, *args: str) -> collections.abc.Iterator[subprocess.Popen[str]]:
+    def process(self, code: str, *args: str) -> collections.abc.Generator[subprocess.Popen[str]]:
         prefix = f"import sys\nsys.path[:] = {sys.path!r}\nimport tine\n"
         with subprocess.Popen(
             [sys.executable, "-c", prefix + textwrap.dedent(code), str(self.root), *args],
@@ -1485,7 +1485,7 @@ def setUp(self) -> None:
         self.addCleanup(patched.stop)
 
     @contextlib.contextmanager
-    def running(self) -> collections.abc.Iterator[list[object]]:
+    def running(self) -> collections.abc.Generator[list[object]]:
         execve: list[object] = []
         with unittest.mock.patch.object(os, "execve", side_effect=lambda *a: execve.extend(a)):
             yield execve
@@ -1824,7 +1824,7 @@ def setUp(self) -> None:
         self.addCleanup(environment.stop)
 
     @contextlib.contextmanager
-    def running(self) -> collections.abc.Iterator[list[object]]:
+    def running(self) -> collections.abc.Generator[list[object]]:
         execve: list[object] = []
         self.served: list[object] = []
         with contextlib.ExitStack() as patches:

box/sandbox_test.py

@@ -13,7 +13,7 @@
 import tempfile
 import unittest
 import unittest.mock
-from collections.abc import Iterator
+from collections.abc import Generator
 from contextlib import contextmanager, redirect_stdout, suppress
 from pathlib import Path
 
@@ -36,7 +36,7 @@ def _tools(root: Path) -> Path:
 
 
 @contextmanager
-def _project() -> Iterator[tuple[Path, Path]]:
+def _project() -> Generator[tuple[Path, Path]]:
     """Enter a temporary project directory, with a tools tree beside it."""
     with tempfile.TemporaryDirectory(prefix="sandbox-test.", dir="/var/tmp") as scratch:
         root = Path(scratch)

image/finalize.py

@@ -14,7 +14,7 @@
 import shutil
 import subprocess
 import sys
-from collections.abc import Iterator, Sequence
+from collections.abc import Generator, Sequence
 from pathlib import Path
 from typing import TypedDict
 
@@ -55,7 +55,7 @@ def image(
     program: str,
     lowers: Sequence[str | Path] | None = None,
     binds: Sequence[tuple[str | Path, str | Path]] | None = None,
-) -> Iterator[Path]:
+) -> Generator[Path]:
     """Mount the image stack the spec names and yield the finalized tree."""
     with rootfs.rootfs(
         "/buildroot", lowers=spec["lower"] if lowers is None else lowers, binds=binds

image/kmod.py

@@ -14,7 +14,7 @@
 import fnmatch
 import json
 import os
-from collections.abc import Iterable, Iterator, Mapping, Sequence
+from collections.abc import Generator, Iterable, Iterator, Mapping, Sequence
 from contextlib import contextmanager
 from pathlib import Path, PurePosixPath
 from typing import NamedTuple, Self, cast
@@ -261,7 +261,7 @@ def _each(self, head: Handle | None) -> Iterator[Handle]:
             entry = cast(Handle | None, self._lib.kmod_list_next(head, entry))
 
     @contextmanager
-    def _lookup(self, name: str) -> Iterator[Handle | None]:
+    def _lookup(self, name: str) -> Generator[Handle | None]:
         mod = ctypes.c_void_p()
         if self._lib.kmod_module_new_from_name(self._ctx, name.encode(), ctypes.byref(mod)) < 0:
             yield None

package/installer.py

@@ -12,7 +12,7 @@
 
 import os
 import shutil
-from collections.abc import Callable, Iterator
+from collections.abc import Callable, Generator
 from contextlib import contextmanager
 from pathlib import Path
 from typing import TypedDict
@@ -72,7 +72,7 @@ class InstallSpec(TypedDict):
 
 
 @contextmanager
-def fresh_machine_id(installroot: Path) -> Iterator[None]:
+def fresh_machine_id(installroot: Path) -> Generator[None]:
     """Leave a fresh root the marker systemd initializes on first boot, and an existing one be."""
     etc = installroot / "etc"
     etc.mkdir(parents=True, exist_ok=True)

package_system/deb/deb822.py

@@ -4,7 +4,7 @@
 """Small, strict readers for Debian's Deb822 metadata."""
 
 import io
-from collections.abc import Iterable, Iterator
+from collections.abc import Generator, Iterable, Iterator
 from contextlib import contextmanager
 from pathlib import Path
 from typing import BinaryIO, NamedTuple, cast
@@ -119,7 +119,7 @@ class Package(NamedTuple):
 
 
 @contextmanager
-def open_text(path: Path) -> Iterator[Iterable[str]]:
+def open_text(path: Path) -> Generator[Iterable[str]]:
     """Open a Deb822 file as text, and detect its compression from its first bytes.
 
     A byte that is not UTF-8 raises while the caller iterates inside the `with` block. This function

package_system/deb/install.py

@@ -20,7 +20,7 @@
 import stat
 import sys
 import tempfile
-from collections.abc import Iterator
+from collections.abc import Generator
 from contextlib import contextmanager
 from pathlib import Path
 
@@ -103,7 +103,7 @@ def _replace(path: Path, content: bytes, mode: int) -> None:
 
 
 @contextmanager
-def denied_daemons(installroot: Path) -> Iterator[None]:
+def denied_daemons(installroot: Path) -> Generator[None]:
     """Install a `policy-rc.d` that denies daemon starts, and remove it after the transaction.
 
     No package ships this file. It belongs to the administrator, so the image must not keep the

package_system/pacman/alpm.py

@@ -17,7 +17,7 @@
 import gzip
 import io
 import tarfile
-from collections.abc import Iterator
+from collections.abc import Generator, Iterator
 from contextlib import ExitStack, contextmanager
 from pathlib import Path
 from typing import IO, NamedTuple, NoReturn, Self, cast
@@ -406,7 +406,7 @@ def _explained(self, error: int, data: ctypes._Pointer[_List]) -> list[str]:
         return []
 
     @contextmanager
-    def _transaction(self) -> Iterator[None]:
+    def _transaction(self) -> Generator[None]:
         if self._lib.alpm_trans_init(self._handle, _NO_FLAGS) != 0:
             self._fail("cannot start a transaction")
         try:

package_system/rpm/build_test.py

@@ -9,7 +9,7 @@
 import subprocess
 import tempfile
 import unittest
-from collections.abc import Callable, Iterator
+from collections.abc import Callable, Generator
 from pathlib import Path
 from typing import cast, override
 from unittest import mock
@@ -350,7 +350,7 @@ def run(
                         return subprocess.CompletedProcess([], result)
 
                     @contextlib.contextmanager
-                    def mounted(trees: list[Path] = directories) -> Iterator[None]:
+                    def mounted(trees: list[Path] = directories) -> Generator[None]:
                         try:
                             yield
                         finally:

remote_cache/status.py

@@ -28,7 +28,7 @@
 import struct
 import tempfile
 import threading
-from collections.abc import Callable, Iterator
+from collections.abc import Callable, Generator
 from contextlib import contextmanager
 from pathlib import Path
 from typing import Any, override
@@ -114,7 +114,7 @@ def __init__(self, path: str, report: Report, attend: Attend) -> None:
 
 
 @contextmanager
-def serving(root: Path, report: Report, attend: Attend = lambda pid: None) -> Iterator[Path]:
+def serving(root: Path, report: Report, attend: Attend = lambda pid: None) -> Generator[Path]:
     """A socket answering for `root` for as long as the block runs.
 
     A socket file left behind by a killed shim would refuse the next bind, so it is removed first.

rootfs/rootfs.py

@@ -15,7 +15,7 @@
 import shutil
 import stat
 import tempfile
-from collections.abc import Iterator, Mapping, Sequence
+from collections.abc import Generator, Mapping, Sequence
 from contextlib import ExitStack, contextmanager
 from enum import Enum, auto
 from pathlib import Path
@@ -170,7 +170,7 @@ def capture(tree: Path) -> None:
 
 
 @contextmanager
-def capture_on_exit(tree: str | Path) -> Iterator[Path]:
+def capture_on_exit(tree: str | Path) -> Generator[Path]:
     """Capture a tree after use without hiding an error from the body."""
     tree = Path(tree)
     try:
@@ -191,7 +191,7 @@ def capture_on_exit(tree: str | Path) -> Iterator[Path]:
 
 
 @contextmanager
-def source_overlay(source: Path, target: Path) -> Iterator[Path]:
+def source_overlay(source: Path, target: Path) -> Generator[Path]:
     """Mount `source` at `target` as an overlay, and discard every write when the context exits.
 
     `rootfs()` decodes the `.wh.` and `.esc.` marker files of a stored image layer. This function
@@ -214,7 +214,7 @@ def source_overlay(source: Path, target: Path) -> Iterator[Path]:
 
 
 @contextmanager
-def readonly_project(project: Path, outputs: Mapping[Path, Path]) -> Iterator[None]:
+def readonly_project(project: Path, outputs: Mapping[Path, Path]) -> Generator[None]:
     """Make `project` read-only and change into it, but keep each output directory writable.
 
     `outputs` maps an output directory under `project` to a mount point outside `project`.
@@ -280,7 +280,7 @@ def _apivfs(stack: ExitStack, target: Path) -> None:
 
 
 @contextmanager
-def chroot(target: str | Path) -> Iterator[Path]:
+def chroot(target: str | Path) -> Generator[Path]:
     """Temporarily enter an already-mounted target root."""
     with _chroot(Path(target)):
         yield Path("/")
@@ -298,7 +298,7 @@ def rootfs(
     apivfs: bool = False,
     binds: Sequence[tuple[str | Path, str | Path]] | None = None,
     chroot: bool = False,
-) -> Iterator[Path]:
+) -> Generator[Path]:
     """Mount a bind or overlay root, optionally chrooting and persisting its output.
 
     Persistent overlay uppers and bind sources with `capture_bind=True` are captured after all

tools/dev_test.py

@@ -13,7 +13,7 @@
 import time
 import tomllib
 import unittest
-from collections.abc import Iterator
+from collections.abc import Generator
 from pathlib import Path
 from typing import Any, cast, override
 from unittest import mock
@@ -321,7 +321,7 @@ def test_refuses_to_overwrite_custom_zed_settings(self) -> None:
         self.assertEqual(settings.read_text(), '{"tab_size": 4}\n')
 
     @contextlib.contextmanager
-    def server(self, package: str) -> Iterator[LanguageServer]:
+    def server(self, package: str) -> Generator[LanguageServer]:
         command, env = self.launch(package)
         # Exercise Zed's configurationFile expansion without the CLI configuration as a fallback.
         env.pop("TY_CONFIG_FILE")

util.py

@@ -18,7 +18,7 @@
 import time
 import urllib.error
 import urllib.request
-from collections.abc import Callable, Iterator
+from collections.abc import Callable, Generator
 from contextlib import contextmanager
 from pathlib import Path
 from typing import IO, NoReturn, TextIO, cast
@@ -244,7 +244,7 @@ def remove_path(path: Path, with_parents: bool = False) -> None:
 
 
 @contextmanager
-def atomic_text_writer(path: Path) -> Iterator[TextIO]:
+def atomic_text_writer(path: Path) -> Generator[TextIO]:
     """Yield a UTF-8 stream and atomically replace its destination on success."""
     path.parent.mkdir(parents=True, exist_ok=True)
     mode = stat.S_IMODE(path.stat().st_mode) if path.exists() else 0o644
@@ -261,7 +261,7 @@ def atomic_text_writer(path: Path) -> Iterator[TextIO]:
 
 
 @contextmanager
-def text_destination(path: Path) -> Iterator[TextIO]:
+def text_destination(path: Path) -> Generator[TextIO]:
     """Yield a UTF-8 stream for a path, or for stdout when the caller named `-`.
 
     A driver published as a run target is asked for its output by a caller that has nowhere to put