findpython fails with pyenv shim (exit 127) on Poetry 2.x – “Command .../pyenv/shims/python … returned non‑zero exit status 127”

Description

Environment

• OS Ubuntu 22.04

• Poetry 2.1.2 (installed via pipx install --suffix "@2.1.2" --python ~/.pyenv/versions/3.12.7/bin/python poetry==2.1.2)

• Python used by pyenv 3.12.7 (pyenv install 3.12.7)

• pyenv 2.4.0

Steps to Reproduce

1. install Poetry 2 inside a pipx venv with the same interpreter
pipx install --suffix "@2.1.2" --python ~/.pyenv/versions/3.12.7/bin/python poetry==2.1.2

2. run poetry init (interactive or --no-interaction)
/home/<user>/.local/pipx/venvs/poetry@2-1-2/bin/poetry init

After answering the interactive prompts Poetry aborts with:
Command '['/home//.pyenv/shims/python', '-EsSc', 'import sys; print(sys.executable)']' returned non-zero exit status 127.

Poetry 1.8.5 on the same machine performs poetry /home/<user>/.local/pipx/venvs/poetry@1.8.5/bin/poetry init successfully.

Workarounds

Setting the following configuration makes Poetry 2.x work without errors:

/home/<user>/.local/pipx/venvs/poetry@2-1-2/bin/poetry config virtualenvs.use-poetry-python true

Poetry Installation Method

pipx

Operating System

Ubuntu 22.04

Poetry Version

2.1.2

Poetry Configuration

cache-dir = "/home/<user>/.cache/pypoetry"
data-dir = "/home/<user>/.local/share/pypoetry"
installer.max-workers = null
installer.no-binary = null
installer.only-binary = null
installer.parallel = true
installer.re-resolve = true
keyring.enabled = true
python.installation-dir = "{data-dir}/python"  # /home/<user>/.local/share/pypoetry/python
requests.max-retries = 0
solver.lazy-wheel = true
system-git-client = false
virtualenvs.create = true
virtualenvs.in-project = null
virtualenvs.options.always-copy = false
virtualenvs.options.no-pip = false
virtualenvs.options.system-site-packages = false
virtualenvs.path = "{cache-dir}/virtualenvs"  # /home/<user>/.cache/pypoetry/virtualenvs
virtualenvs.prompt = "{project_name}-py{python_version}"

Start by reproducing the failure with the provided pipx, pyenv, and Poetry 2.1.2 commands, then compare it with Poetry 1.8.5 and the virtualenvs.use-poetry-python workaround. Trace the findpython path involved in the reported interpreter command; the work is done when the original setup completes successfully without requiring that configuration.