Address review: deterministic dir-name tests + doc callouts

- test_full_session_id_remains_in_the_log: filter to openjd.sessions
  records and default the session_id getattr to None, so a dropped
  LoggerAdapter fails the assertion instead of passing vacuously.
- Replace the probabilistic name-inspection assertions with a
  deterministic check that TempDir is called with prefix="".
- Assert the name length as a <= budget ceiling rather than == to an
  incidental CPython detail.
- Narrow the concurrent test's except from BaseException to Exception
  (CodeQL).
- Fix TempDir.prefix docstring (default is None -> "tmp", not "").
- Note on working_directory / retain_working_dir that the directory name
  no longer carries session identity; the log holds that mapping.

Signed-off-by: Stephen Crowe <6042774+crowecawcaw@users.noreply.github.com>

Author: crowecawcaw

src/openjd/sessions/_session.py

@@ -417,6 +417,12 @@ def __init__(
                 within all actions running within this session. Defaults to None.
             retain_working_dir (bool, optional): If set, then the Session's Working Directory
                 is not deleted when this Session object is deleted. Defaults to False.
+                Note: the working directory's *name* no longer encodes the session id
+                (it is mkdtemp()'s random characters and nothing else), so a retained
+                directory is not attributable to a session by its name alone. The
+                session log records the working directory's full path against the
+                session id; that log is how a retained or orphaned directory is
+                resolved back to its session.
             user (Optional[SessionUser]): The specific OS user to run subprocesses as, and whom
                 will have permissions to the Session's Working Directory.
                 Defaults to the current process user.
@@ -632,6 +638,10 @@ def working_directory(self) -> Path:
         This is available in a Job Template's format string expressions as
         Session.WorkingDirectory
 
+        The directory's name is generated (mkdtemp()'s random characters) and
+        carries no part of the session id, so do not parse identity out of it;
+        the session id is recorded against this path in the session log instead.
+
         Raises:
             RuntimeError: If this Session has no working directory, which means
                 construction did not complete.

src/openjd/sessions/_tempdir.py

@@ -261,7 +261,9 @@ def __init__(
             dir (Optional[Path]): The directory in which to create the temp dir.
                 Defaults to tempfile.gettempdir().
             prefix (Optional[str]): A prefix to use in the name of the generated temp dir.
-                Defaults to "".
+                Defaults to None, which mkdtemp() replaces with its "tmp" template
+                (3 characters). Pass "" for no prefix at all -- a shorter name, and
+                not the same as omitting the argument.
             user (Optional[SessionUser]): A group that will own the created directory.
                 The group-write bit will be set on the directory if this option is supplied.
                 Defaults to this process' effective user/group.

test/openjd/sessions_v0/test_session.py

@@ -54,6 +54,7 @@
     LogContent,
 )
 from openjd.sessions import _path_mapping as path_mapping_impl_mod
+from openjd.sessions import _session as session_module
 from openjd.sessions._action_filter import ActionMessageKind
 from openjd.sessions._os_checker import is_posix, is_windows
 from openjd.sessions._logging import LoggerAdapter, LogExtraInfo
@@ -564,6 +565,12 @@ class TestSessionWorkingDirectoryName:
     DEADLINE_SHAPED_ID = f"session-{uuid.uuid4().hex}"
 
     def test_working_directory_name_length_is_bounded(self) -> None:
+        # A ceiling, not an equality: the exact count is mkdtemp()'s to choose
+        # (CPython currently yields 8 characters, hence the constant) and a stdlib
+        # change to a *shorter* name would not be a regression. What must not
+        # regress is the budget -- passing the 40-character session id as a prefix
+        # cost 48.
+
         # GIVEN
         job_params = dict[str, ParameterValue]()
 
@@ -572,28 +579,29 @@ def test_working_directory_name_length_is_bounded(self) -> None:
             session_id=self.DEADLINE_SHAPED_ID, job_parameter_values=job_params
         ) as session:
             # THEN
-            assert len(session.working_directory.name) == SESSION_DIR_NAME_LENGTH
-            # Guard on the budget itself, independent of the constant: this cost 48.
-            assert len(session.working_directory.name) <= 8
+            assert len(session.working_directory.name) <= SESSION_DIR_NAME_LENGTH
 
-    def test_working_directory_name_carries_no_part_of_the_session_id(self) -> None:
-        # prefix="" rather than None: None would restore mkdtemp()'s "tmp" template,
-        # so guard the distinction and not just the absence of the id.
+    def test_working_directory_is_created_with_an_empty_prefix(self) -> None:
+        # prefix="" rather than None is the load-bearing choice: None restores
+        # mkdtemp()'s "tmp" template (3 characters) and the session id (48) is what
+        # we removed. Assert the argument we pass, not a sample of the random name:
+        # inspecting the name for the *absence* of a prefix is probabilistic -- a
+        # random [a-z0-9_] name can happen to begin "tmp" -- while the call is exact.
 
         # GIVEN
         job_params = dict[str, ParameterValue]()
 
         # WHEN
-        with Session(
-            session_id=self.DEADLINE_SHAPED_ID, job_parameter_values=job_params
-        ) as session:
-            # THEN
-            name = session.working_directory.name
-            assert not name.startswith("tmp")
-            assert "session" not in name
-            assert not any(
-                self.DEADLINE_SHAPED_ID[-n:] in name for n in range(4, len(self.DEADLINE_SHAPED_ID))
-            )
+        with patch.object(session_module, "TempDir", wraps=session_module.TempDir) as mock_tempdir:
+            with Session(
+                session_id=self.DEADLINE_SHAPED_ID, job_parameter_values=job_params
+            ) as session:
+                # THEN
+                # The first TempDir call is the working directory; the second is
+                # the nested embedded_files directory.
+                assert mock_tempdir.call_args_list[0].kwargs["prefix"] == ""
+                # ... and nothing of the session id survived into the name.
+                assert self.DEADLINE_SHAPED_ID not in session.working_directory.name
 
     @pytest.mark.usefixtures("caplog")  # built-in fixture
     def test_full_session_id_remains_in_the_log(self, caplog: pytest.LogCaptureFixture) -> None:
@@ -617,9 +625,15 @@ def test_full_session_id_remains_in_the_log(self, caplog: pytest.LogCaptureFixtu
                 m == f"Session Working Directory: {str(session.working_directory)}"
                 for m in caplog.messages
             )
+            # caplog.records collects from every logger propagating to root, so
+            # filter to this library's before asserting the extra is present --
+            # and default to None, not the expected id, so a record that is
+            # *missing* the extra fails rather than passing vacuously (which is
+            # precisely the regression -- a dropped LoggerAdapter -- this guards).
+            session_records = [r for r in caplog.records if r.name.startswith("openjd.sessions")]
+            assert session_records
             assert all(
-                getattr(r, "session_id", self.DEADLINE_SHAPED_ID) == self.DEADLINE_SHAPED_ID
-                for r in caplog.records
+                getattr(r, "session_id", None) == self.DEADLINE_SHAPED_ID for r in session_records
             )
 
     @pytest.mark.usefixtures("tmp_path")  # built-in fixture
@@ -662,7 +676,7 @@ def test_concurrent_sessions_in_one_root_get_distinct_directories(self, tmp_path
         job_params = dict[str, ParameterValue]()
         sessions: list[Session] = []
         lock = threading.Lock()
-        errors: list[BaseException] = []
+        errors: list[Exception] = []
 
         def make_session() -> None:
             try:
@@ -671,7 +685,7 @@ def make_session() -> None:
                     job_parameter_values=job_params,
                     session_root_directory=tmp_path,
                 )
-            except BaseException as err:  # pragma: nocover - only on a failure
+            except Exception as err:  # pragma: nocover - only on a failure
                 with lock:
                     errors.append(err)
                 return