Import resolution doesn't understand editable installation with a non-standard `package-dir`.

[Andrew-NCT]

Environment data

• Language Server version: 2023.12.1
• OS and version: win32 x64
• Python version (and distribution if applicable, e.g. Anaconda):
• python.analysis.indexing: true
• python.analysis.typeCheckingMode: off

Code Snippet

from myproj.module import variable

If myproj is imported in editable mode and there isn't a myproj/ directory anywhere, pylance marks it as a missing import.

Repro Steps

Create a directory structure like

Project/
    .venv/
    src/
        __init__.py
        module.py
    pyproject.toml

Where pyproject.toml is

[build-system]
requires = ["setuptools"]
build-backend = "setuptools.build_meta"

[project]
name = "myproj"
version = "1"

[tool.setuptools.package-dir]
myproj = "src"

__init__.py is

from myproj.module import variable
from src.module import variable2

and the venv is created with python -m venv .venv. Run .\.venv\Scripts\activate and then pip install -e ..

Expected behavior

Pylance should inform me that src.module is an error via reportMissingImports, while myproj.module should be understood as valid.

Actual behavior

It does the opposite; it likes src.module, while throwing reportMissingImports at myproj.module.

Logs

There's not really any relevant logs.

I'm aware that either

• You're going to tell me about some setting I couldn't find which uses your venv's path to resolve imports rather than finding modules.
• This esssentially constitutes a massive feature request.

It's just been bothering me for weeks. Thank you for your help!

[debonte]

What's in the .pth file for your editable install? It needs to be just a path for us to support it. We don't support the use of import hooks. See https://microsoft.github.io/pyright/#/import-resolution?id=editable-installs

Is your venv the selected interpreter within VS Code? See the "Python: Select Interpreter" command in the command palette.

[Andrew-NCT]

The .pth file is

import __editable___myproj_1_finder; __editable___myproj_1_finder.install()

which corresponds to a file __editable___myproj_1_finder.py which seems to be created by Python by default. At the top if it it says

MAPPING = {'myproj': 'C:\\Users\\Andrew\\Code\\Issue\\src'}
NAMESPACES = {}
PATH_PLACEHOLDER = '__editable__.myproj-1.finder' + ".__path_hook__

And the rest of the file seems to be boilerplate / not specific to myproj.

My default Python interpreter path is "python.defaultInterpreterPath": "${workspaceFolder}/.venv" and choosing .venv/Scripts.python.exe doesn't change anything for me.

For reference, I'm using Python 3.12.1

[Andrew-NCT]

I installed it in compat mode, so now the __editable__.myproj-1.pth file is C:\Users\Andrew\Code\Project However, nothing has changed, as I'm pretty sure the Project directory is already automatically in the path. It still doesn't handle the translation between src and myproj.

[debonte]

I see. We don't support that. Our support for editable installs is limited to simple (non-hook) .pth files -- the paths in them are automatically added (by the interpreter) to the path we use for import resolution.

You could make your scenario work by adding a symbolic link: mklink /D myproj src

Improving editable install support isn't a high priority for us at the moment. If you'd like, I can turn this into an enhancement discussion and we can see if it gets enough up-votes to get onto our radar.

[judej]

Moving this issue to discussion as an enhancement request for comments and upvotes.