venv base-executable path does not resolve symlinks using realpath()

mayeut commented 8 months ago

Issue

The home & base-executable keys in pyvenv.cfg do not resolve symlinks using realpath() leading to a broken virtual environment in some cases.

c.f. https://github.com/python/cpython/issues/106045

Environment

Provide at least:

OS: at least Linux
GHA reproducer:
```
name: Python test bitness
```

on: push: branches:

venv-reproducer workflow_dispatch:
allow manual runs on branches without a PR

jobs: venv: runs-on: ubuntu-22.04 steps:

uses: actions/setup-python@v5 with: python-version: "3.11"
name: test run: | set -x fail_venv=0 fail_virtualenv=0 sudo apt-get update &>/dev/null sudo apt-get install -y python3-distutils &>/dev/null python3 -m pip install virtualenv python3 -m venv cp311-1 cat cp311-1/pyvenv.cfg cp311-1/bin/python -sSEc 'import sys; print(sys.path)' python3 -m virtualenv cp311-2 cat cp311-2/pyvenv.cfg cp311-2/bin/python -sSEc 'import sys; print(sys.path)' ln -sf $(which python3) /usr/local/bin/python3 /usr/local/bin/python3 -m venv cp311-3 || fail_venv=1 cat cp311-3/pyvenv.cfg cp311-3/bin/python -sSEc 'import sys; print(sys.path)' /usr/local/bin/python3 -m virtualenv cp311-4 || fail_virtualenv=1 cp311-4/bin/python -c 'import subprocess' || fail_virtualenv=1 cat cp311-4/pyvenv.cfg cp311-4/bin/python -sSEc 'import sys; print(sys.path)' exit $(( $fail_venv + $fail_virtualenv ))

Output

the cp311-4 is broken & uses the following pyvenv.cfg:

home = /usr/local/bin
implementation = CPython
version_info = 3.11.7.final.0
virtualenv = 20.25.0
include-system-site-packages = false
base-prefix = /opt/hostedtoolcache/Python/3.11.7/x64
base-exec-prefix = /opt/hostedtoolcache/Python/3.11.7/x64
base-executable = /usr/local/bin/python3

/usr/local/bin shall never be referenced in this file as /usr/local/bin/python3 is just a symlink on /opt/hostedtoolcache/Python/3.11.7/x64/bin/python3

importing subprocess fails because the computed sys.path is invalid for this interpreter (/usr/lib/python3.11/lib-dynload is invalid here):

['', '/opt/hostedtoolcache/Python/3.11.7/x64/lib/python311.zip', '/opt/hostedtoolcache/Python/3.11.7/x64/lib/python3.11', '/usr/lib/python3.11/lib-dynload']

ofek commented 7 months ago

Resolving symbolic links would also fix this issue: https://github.com/pypa/virtualenv/issues/2684

gaborbernat commented 7 months ago

PR welcome to address this is welcome 👍

pypa / virtualenv

venv base-executable path does not resolve symlinks using realpath() #2682

allow manual runs on branches without a PR