Hard hang in find_python_version()

[mathrick]

I'm not sure what's causing this, and what details of my environment might be relevant, but I'm encountering a hard hang when calling Finder.find_python_version or Finder.find_all_python_versions. The Python process becomes entirely unresponsive, ignoring Ctrl+C, Ctrl+Z and the like. Killing it from another terminal is the only way to quit.

Environment:

• Ubuntu 20.04
• Python 3.x (tried with 3.6.8 and 3.8.5)
• Using pyenv with pyenv-virtualenv
• Seems to affect all virtualenvs equally

[blueyed]

Try Ctrl-d.

I am seeing this with pyrepl being installed (via pdb++), which ships pythoni, which gets picked up / tried by pythonfinder, but acts as an interactive shell always (ignoring --version etc).

I think pythonfinder maybe should close stdin when trying out existing python interpreters maybe at least.

Of course, try also strace, pstree etc to figure out what happens really.

[mathrick]

@blueyed: you're right, I do have pdb++ installed. Ctrl+D didn't help (I'm assuming because pythonfinder doesn't attach the TTY when spawning subprocesses), but that sounds very likely.

[mathrick]

Now that you mention it, I see pythoni in the ps output, so you're definitely right.

[blueyed]

You might need it several times: press it and wait a few seconds, before pressing it again (to not accidentally close the terminal).