Re-raise error if cannot create file for some reason for soft locks

* updated nomenclature to allign with softlock, added test, added changelog

* moved fcntl import to the test def and added type hints

* another type attempt

* flake fixes

* flake fixes

* changes to resolve issue 147

* fix typo

* flake 8 fix

* test for OSError in SoftFileLock

* flake8 fix

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* PR Feedback

Signed-off-by: Bernát Gábor <bgabor8@bloomberg.net>

* PR Feedback

Signed-off-by: Bernát Gábor <bgabor8@bloomberg.net>

---------

Signed-off-by: Bernát Gábor <bgabor8@bloomberg.net>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Bernát Gábor <bgabor8@bloomberg.net>

docs/changelog.rst

@@ -1,5 +1,9 @@
 Changelog
 =========
+v3.10.6 (2023-03-25)
+--------------------
+- Enhance the robustness of the try/catch block in _soft.py. by :user:`jahrules`.
+
 v3.10.5 (2023-03-25)
 --------------------
 - Add explicit error check as certain UNIX filesystems do not support flock. by :user:`jahrules`.

src/filelock/_soft.py

@@ -2,7 +2,7 @@
 
 import os
 import sys
-from errno import EACCES, EEXIST, ENOENT
+from errno import EACCES, EEXIST
 
 from ._api import BaseFileLock
 from ._util import raise_on_exist_ro_file
@@ -21,17 +21,15 @@ def _acquire(self) -> None:
             | os.O_TRUNC  # truncate the file to zero byte
         )
         try:
-            fd = os.open(self._lock_file, flags, self._mode)
-        except OSError as exception:
-            if exception.errno == EEXIST:  # expected if cannot lock
-                pass
-            elif exception.errno == ENOENT:  # No such file or directory - parent directory is missing
+            file_handler = os.open(self._lock_file, flags, self._mode)
+        except OSError as exception:  # re-raise unless expected exception
+            if not (
+                exception.errno == EEXIST  # lock already exist
+                or (exception.errno == EACCES and sys.platform == "win32")  # has no access to this lock
+            ):  # pragma: win32 no cover
                 raise
-            elif exception.errno == EACCES and sys.platform != "win32":  # pragma: win32 no cover
-                # Permission denied - parent dir is R/O
-                raise  # note windows does not allow you to make a folder r/o only files
         else:
-            self._lock_file_fd = fd
+            self._lock_file_fd = file_handler
 
     def _release(self) -> None:
         os.close(self._lock_file_fd)  # type: ignore # the lock file is definitely not None

tests/test_filelock.py

@@ -185,7 +185,7 @@ def __init__(self, target: Callable[[], None], name: str) -> None:
     def run(self) -> None:
         try:
             super().run()
-        except Exception:  # pragma: no cover
+        except RuntimeError:  # pragma: no cover
             self.ex = sys.exc_info()  # pragma: no cover
 
     def join(self, timeout: float | None = None) -> None:
@@ -337,8 +337,8 @@ def test_context_release_on_exc(lock_type: type[BaseFileLock], tmp_path: Path) -
         with lock as lock_1:
             assert lock is lock_1
             assert lock.is_locked
-            raise Exception
-    except Exception:
+            raise ValueError
+    except ValueError:
         assert not lock.is_locked
 
 
@@ -352,8 +352,8 @@ def test_acquire_release_on_exc(lock_type: type[BaseFileLock], tmp_path: Path) -
         with lock.acquire() as lock_1:
             assert lock is lock_1
             assert lock.is_locked
-            raise Exception
-    except Exception:
+            raise ValueError
+    except ValueError:
         assert not lock.is_locked
 
 
@@ -385,9 +385,8 @@ def test_del(lock_type: type[BaseFileLock], tmp_path: Path) -> None:
 def test_cleanup_soft_lock(tmp_path: Path) -> None:
     # tests if the lock file is removed after use
     lock_path = tmp_path / "a"
-    lock = SoftFileLock(str(lock_path))
 
-    with lock:
+    with SoftFileLock(lock_path):
         assert lock_path.exists()
     assert not lock_path.exists()
 
@@ -399,9 +398,9 @@ def test_poll_intervall_deprecated(lock_type: type[BaseFileLock], tmp_path: Path
 
     with pytest.deprecated_call(match="use poll_interval instead of poll_intervall") as checker:
         lock.acquire(poll_intervall=0.05)  # the deprecation warning will be captured by the checker
-        frameinfo = getframeinfo(stack()[0][0])  # get frameinfo of current file and lineno (+1 than the above lineno)
+        frame_info = getframeinfo(stack()[0][0])  # get frame info of current file and lineno (+1 than the above lineno)
         for warning in checker:
-            if warning.filename == frameinfo.filename and warning.lineno + 1 == frameinfo.lineno:  # pragma: no cover
+            if warning.filename == frame_info.filename and warning.lineno + 1 == frame_info.lineno:  # pragma: no cover
                 break
         else:  # pragma: no cover
             pytest.fail("No warnings of stacklevel=2 matching.")
@@ -490,7 +489,7 @@ def test_wrong_platform(tmp_path: Path) -> None:
     assert inspect.isabstract(BaseFileLock)
 
     lock_type = UnixFileLock if sys.platform == "win32" else WindowsFileLock
-    lock = lock_type(str(tmp_path / "lockfile"))
+    lock = lock_type(tmp_path / "lockfile")
 
     with pytest.raises(NotImplementedError):
         lock.acquire()
@@ -502,5 +501,11 @@ def test_wrong_platform(tmp_path: Path) -> None:
 def test_flock_not_implemented_unix(tmp_path: Path, mocker: MockerFixture) -> None:
     mocker.patch("fcntl.flock", side_effect=OSError(ENOSYS, "mock error"))
     with pytest.raises(NotImplementedError):
-        with FileLock(str(tmp_path / "a.lock")):
+        with FileLock(tmp_path / "a.lock"):
             pass
+
+
+def test_soft_errors(tmp_path: Path, mocker: MockerFixture) -> None:
+    mocker.patch("os.open", side_effect=OSError(ENOSYS, "mock error"))
+    with pytest.raises(OSError, match="mock error"):
+        SoftFileLock(tmp_path / "a.lock").acquire()

whitelist.txt

@@ -7,7 +7,6 @@ enosys
 extlinks
 filelock
 filemode
-frameinfo
 fspath
 getframeinfo
 intersphinx