Unable to debug with Debugpy

• Poetry version: 1.4.0

• Python version: 3.10

• OS version and name: Arch Linux

• I am on the latest stable Poetry version, installed using a recommended method.

• I have searched the issues of this repo and believe that this is not a duplicate.

• I have consulted the FAQ and blog for any relevant entries or release notes.

• If an exception occurs when executing a command, I executed it again in debug mode (-vvv option) and have included the output below.

Issue

Following up on this issue, for some reason nvim-dap is not being able to attach a debugger if I'm running an application using Poetry

If I run using Python directly it works, but using Poetry it automatically closes. If I run from within a Poetry shell, it bootstraps the debugger, but whenever I set breakpoints debugpy throws an error

You can see the details on the original issue.

To replicate the issue you just need to do the following:

1. Create the basic setup without Poetry:

python -m venv venv
venv/bin/python -m pip install Flask

2. Create a vscode/launch.json:

{
   "version": "0.2.0",
   "configurations": [
       {
           "type": "python",
           "request": "launch",
           "name": "Flask",
           "module": "flask",
           "args": ["--app", "foo", "run"],
           "console": "integratedTerminal"
       }
   ]
}

3. Create foo.py:

from flask import Flask

app = Flask(__name__)

@app.route("/")
def hello():
    return "<p>Hello World</p>"

After this, run in your IDE, attach a debugger to it and test. You'll see that it works.

Now, do the same, but on the setup step do the setup using Poetry. After this, tried running the debugger with the Poetry setup. It would either not work (if you try using it with poetry run) or it will not be able to set any breakpoints (if you try using poetry shell)

Start by reproducing the Flask setup with a Python virtual environment and with Poetry, using the vscode/launch.json configuration and the linked nvim-dap-python issue as context. Investigate the differing behavior of poetry run and poetry shell; done means debugpy attaches successfully and breakpoints can be set in both Poetry workflows.