UV Python project is broken: No interpreter found for path

[mskonovalov]

What happened?

Works just fine in Devbox 0.13.6
But broken in 0.14.0

Info: Ensuring packages are installed.
✓ Computed the Devbox environment.
error: No interpreter found for path `.../.venv/bin/python` in managed installations or system path
Error: error running script "it-tests" in Devbox: exit status 2

The issue is I have a venv in the subfolder, but it always tries to look in the root of the project :(

Will try to prepare the reproduction example.

Likely related to #2478
#2411

cc @yemaney

Steps to reproduce

1. Create a project with python venv inside subfolder
2. try to run any command via UV
3. see the error

Command

run

devbox.json

{
  "$schema": "https://raw.githubusercontent.com/jetify-com/devbox/0.13.7/.schema/devbox.schema.json",
  "packages": [
    "python@3.10",
    "uv@0.4.30"
  ],
  "shell": {
    "init_hook": [
      "alias cdt='cd src/packages/toolkit'",
      ". $VENV_DIR/bin/activate"
    ],
    "scripts": {
      "unit-tests": ["cdt", "uv run pytest -m unit \"$@\""],
      "it-tests": ["cdt", "uv run pytest -m integration \"$@\""]
    }
  },
  "env": {
    "VENV_DIR": "./src/packages/toolkit/.venv",
  }
}

Devbox version

0.14.0

Nix version

2.27.1

What system does this bug occur on?

macOS (Apple Silicon)

Debug logs

No response

[mskonovalov]

BTW is it possible to version plugins independently? So that you can pin specific python plugin version while still be able to update devbox?

[mskonovalov]

here is the example repo https://github.com/mskonovalov/devbox_bug
clone it and try to run devbox run it-tests
then you will see the following error

error: No interpreter found for path `/Users/kms/work/devbox_bug/.venv/bin/python` in managed installations or system path
Error: error running script "it-tests" in Devbox: exit status 2

Same result if you do

devbox shell
uv sync

[Riezebos]

Did you try adding "UV_PYTHON": "$PWD/.venv/bin/python" as fix mentioned in this comment on the linked issue? #2411 (comment)

[mskonovalov]

I did, it does not help, still looking in the wrong place

[yemaney]

The easiest fix right now is to set an extra env var in the devbox.json for UV_PYTHON that is the full path to the python executable under your custom VENV_DIR directory.

{
  "$schema": "https://raw.githubusercontent.com/jetify-com/devbox/0.13.7/.schema/devbox.schema.json",
  "packages": ["python@3.10", "uv@0.4.30"],
  "shell": {
    "init_hook": [
      "alias cdt='cd src/packages/toolkit'",
      ". $VENV_DIR/bin/activate"
    ],
    "scripts": {
      "unit-tests": ["cdt", "uv run pytest -m unit \"$@\""],
      "it-tests": ["cd src/packages/toolkit", "uv run pytest -m integration \"$@\""]
    }
  },
  "env": {
    "VENV_DIR": "./src/packages/toolkit/.venv",
    "UV_PYTHON": "/workspaces/devbox/devbox_bug/src/packages/toolkit/.venv/bin/python"
  }
}

devbox_bug on  main [!?] via 🐍 v3.10.16 (.venv) via ❄️  impure (nix-shell-env) 
⬢ [Docker] ❯ env | grep UV
UV_PYTHON=/workspaces/devbox/devbox_bug/src/packages/toolkit/.venv/bin/python

devbox_bug on  main [!?] via 🐍 v3.10.16 (.venv) via ❄️  impure (nix-shell-env) 
⬢ [Docker] ❯ devbox run
Available scripts:
* it-tests
* unit-tests

devbox_bug on  main [!?] via 🐍 v3.10.16 (.venv) via ❄️  impure (nix-shell-env) 
⬢ [Docker] ❯ devbox run it-tests
Info: Running script "it-tests" on /workspaces/devbox/devbox_bug
================================================== test session starts ==================================================
platform linux -- Python 3.10.16, pytest-8.3.4, pluggy-1.5.0
rootdir: /workspaces/devbox/devbox_bug/src/packages/toolkit
configfile: pyproject.toml
testpaths: tests
plugins: dotenv-0.5.2, mock-3.14.0, testmon-2.1.1, xdist-3.6.1
collected 1 item                                                                                                        

tests/integration/test_rules.py .                                                                                 [100%]

=================================================== 1 passed in 0.02s ===================================================

[mskonovalov]

Thanks, I'll check. Although I believe it is not a good solution to hardcode somebody's local full path to the project :)
Would be nice to fix it properly

[yemaney]

@mskonovalov I've just made a pull request for this. 😅
You can upvote / comment on it to help maintainers to merge it.