Hi there, when I run

./pants check {my_file.py}

I see the "pants-sandbox-xxx" is not a valid Python package name error. I wonder if anyone has seen this issue and what could be the root cause? I am using python 3.9, mypy==1.4.1. Thanks!

PANTS_PYTHON_INTERPRETER_CONSTRAINTS=['==3.9.*'] on MacOS_ARM64

11:17:59.03 [WARN] DEPRECATED: Running Pants in an external Python interpreter via a

./pants` script is scheduled to be removed in version 2.18.0.dev0.`

11:18:10.08 [INFO] Completed: Building mypy.pex from mypy.lock

11:18:23.49 [ERROR] Completed: Typecheck using MyPy - mypy - mypy failed (exit code 2).

pants-sandbox-D4V2qW is not a valid Python package name

✕ mypy failed.

taking a wild guess here: you may have your python source in the repo root? and when pants runs

mypy

with those sources then in the root of the sandbox, the sandbox will be seen as the package name.

Definitely go down the standard debug path and throw in a

--keep-sandboxes=on_failure

.

Thanks! I applied the --keep-sandboxes=on_failures option. The extra console log I see is

13:12:57.26 [INFO] Preserving local process execution dir /private/var/folders/n_/gd3n_80j2hn188krq4qj_2880000gn/T/pants-sandbox-SoUXMA for Run MyPy on 1 file.

Yup; so cd

/private/var/folders/n_/gd3n_80j2hn188krq4qj_2880000gn/T/pants-sandbox-SoUXMA

and have a look around. What do you see? What is in

__run.sh

? What happens when you run

./__run.sh

?

Thanks for sharing the knowledge! Running __run.sh generates the same error "pants-sandbox-SoUXMA is not a valid Python package name".

Ok, great. You should be able to figure it out from there. You have everything you need in the sandbox to debug.