tox can produce exception if the log folder does not exsits #3632
Description
Issue
Since yesterday, for some yet unknown reason, I am facing a very weird stacktrace exception from running tox on an environment, caused by a missing log folder. I checked the code and apparently there is the assumption that the path exists.
Probably the removal of the log folder is caused by something else but the bug is real, the code should attempt to create the path if it does not exist yet.
lint: internal error Traceback (most recent call last): File "/Users/ssbarnea/code/a/devtools/ansible-dev-tools/.tox/.tox/lib/python3.14/site-packages/tox/session/cmd/run/single.py", line 48, in _evaluate code, outcomes = run_commands(tox_env, no_test) ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^ File "/Users/ssbarnea/code/a/devtools/ansible-dev-tools/.tox/.tox/lib/python3.14/site-packages/tox/session/cmd/run/single.py", line 85, in run_commands status_main = run_command_set(tox_env, "commands", chdir, ignore_errors, outcomes) File "/Users/ssbarnea/code/a/devtools/ansible-dev-tools/.tox/.tox/lib/python3.14/site-packages/tox/session/cmd/run/single.py", line 106, in run_command_set current_outcome = tox_env.execute( cmd.args, ...<3 lines>... run_id=f"{key}[{at}]", ) File "/Users/ssbarnea/code/a/devtools/ansible-dev-tools/.tox/.tox/lib/python3.14/site-packages/tox/tox_env/api.py", line 426, in execute with self.execute_async(cmd, stdin, show, cwd, run_id, executor) as status: ~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/ssbarnea/.config/uv/python/cpython-3.14.0-macos-aarch64-none/lib/python3.14/contextlib.py", line 148, in __exit__ next(self.gen) ~~~~^^^^^^^^^^ File "/Users/ssbarnea/code/a/devtools/ansible-dev-tools/.tox/.tox/lib/python3.14/site-packages/tox/tox_env/api.py", line 480, in execute_async self._log_execute(request, execute_status) ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/ssbarnea/code/a/devtools/ansible-dev-tools/.tox/.tox/lib/python3.14/site-packages/tox/tox_env/api.py", line 486, in _log_execute self._write_execute_log(self.name, self.env_log_dir / f"{self._log_id}-{request.run_id}.log", request, status) ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/ssbarnea/code/a/devtools/ansible-dev-tools/.tox/.tox/lib/python3.14/site-packages/tox/tox_env/api.py", line 490, in _write_execute_log with log_file.open("wt", encoding="utf-8") as file: ~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/ssbarnea/.config/uv/python/cpython-3.14.0-macos-aarch64-none/lib/python3.14/pathlib/__init__.py", line 776, in open return io.open(self, mode, buffering, encoding, errors, newline) ~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FileNotFoundError: [Errno 2] No such file or directory: '/Users/ssbarnea/code/a/devtools/ansible-dev-tools/.tox/lint/log/3-commands[0].log' Environment
Using tox-uv, might be related.
Output of running tox
Output of tox -rvv
Minimal example
After making a patch to create the folder the exception no longer appears and I can see:
ls -1 .tox/lint/log 3-commands[0].log The interesting part is that executions 1 and 2 are missing. I have no pre tasks so I suspect something like packaging is removing the log file in this case.
I was able to identify that what triggers the bug is using tox-uv and setting runner = "uv-venv-lock-runner". I will try to fix this in tox-uv but I still think that we need to patch tox for creating this folder and avoid an ugly stacktrace.