fish_config: No module named 'distutils.spawn'

[Natsurii]

I was trying to setup fish on fresh install of Raspbian OS 32bit on RPi4.
Running fish_config threw a Python web error:
Traceback (most recent call last): File "/usr/share/fish/tools/web_config/webconfig.py", line 11, in <module> from distutils.spawn import find_executable ModuleNotFoundError: No module named 'distutils.spawn'

This behaviour also shows on sh -c 'env HOME=$(mktemp -d) fish'

Here is some technical details.
$ fish --version
fish, version 3.1.2

$ uname -a
Linux raspberrypi 5.4.72-v7l+ #1356 SMP Thu Oct 22 13:57:51 BST 2020 armv7l GNU/Linux

$ echo $TERM
xterm-256color

$python3 --version
Python 3.7.3

[mqudsi]

What method did you use to install fish?

[zanchey]

Debian packages don't install distutils by default, so you need to apt install python3-distutils.

Either we should add a dependency to the Debian packages or drop the use of distutils.

[faho]

We use distutils for two really rather small things:

• Checking if termux-open-url exists (via distutils.spawn.find_executable, which we explain elsewhere is quite bad and fails to check that the path is executable!)

• Checking if the macOS version is >= 10.12.5 via distutils.LooseVersion

I'm just going to remove the former - we already check if $PATH includes a path with "com.termux" in it. If it turns out it's needed we can reuse the path checking we do elsewhere already.

The latter I'd replace with:

import platform

def isMacOS10_12_5_OrLater():
    """ Return whether this system is macOS 10.12.5 or a later version. """
    try:
        version = [int(x) for x in platform.mac_ver()[0].split(".")]
        if version[0] < 10: return False
        if version[0] > 10: return True
        if version[1] < 12: return False
        if version[1] > 12: return True
        if version[2] < 5: return False
        return True
    except:
        return False

If anyone on macOS could confirm this is working that'd be grand.

Alternatively we could remove that check altogether - macOS 10.12 has been EOL for over a year, and the last release was 10.12.6.

[zanchey]

I think you can just compare the version elements as a list directly:

def isMacOS10_12_5_OrLater():
    return [int(x) for x in platform.mac_ver()[0].split(".")] >= [10, 12, 5]

[faho]

Oooh, that's cool. I'd have thought that does a simple pair-wise comparison, which would fail e.g. on 10.13.4, but it turns out it does a "compare as long as they're equal" thing.

It still needs a try/catch for when there's no mac_ver() to give because it's not a mac, but otherwise, yeah, that should work. As long as apple doesn't start giving version numbers in song instead, that is.

[faho]

Alright, let's just do it.

@zanchey I'm assuming we can drop the python3-distutils recommends from debian/control now?

[zanchey]

@zanchey I'm assuming we can drop the python3-distutils recommends from debian/control now?

done in f396a43

[floam]

It still needs a try/catch for when there's no mac_ver() to give because it's not a mac, but otherwise, yeah, that should work. As long as apple doesn't start giving version numbers in song instead, that is.

I think mac_ver() exists everywhere.