Re: [PATCH v4 4/4] ci: install python on ubuntu

From: Jiang Xin <worldhello.net@gmail.com>
Date: Nov 27, 2022, 09:01 UTC
Message-ID: <CANYiYbGmZjBzRNd9W2kws9KCnxXAvVpkGNUzRJs4LtLKW+ukmQ@mail.gmail.com>
In-Reply-To: <xmqq4julb5nk.fsf@gitster.g>

On Sun, Nov 27, 2022 at 8:30 AM Junio C Hamano <gitster@pobox.com> wrote:

Show 6 quoted lines

> > Since the "ubuntu-latest" runner image has a higher version, so its safe
> > to use "python2" or "python3" package name.
>
> Makes sense.  Just out of curiousity (read: not a suggestion to
> change anything), what happens if you say "apt install python" on a
> recent system?

In order to reproduce, I start a docker container like  this:

    $ docker run -it --rm ubuntu:22.04 /bin/bash

Fetch the latest apt source list, by running:

    $ apt-get update

Then install python with the following errors:

    $ apt-get install python
    Reading package lists... Done
    Building dependency tree... Done
    Reading state information... Done
    Package python is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
However the following packages replace it:
  2to3 python2-minimal python2 dh-python python-is-python3

E: Package 'python' has no installation candidate

We can also find python package name from packages.ubuntu.com:

1. form the link below, we can say Ubuntu 18.04 is the last version
(LTS?) which has python package:

    https://packages.ubuntu.com/search?keywords=python&searchon=names&suite=all&section=all

2. Ubuntu 20.04 is the first version (LTS) which rename its python
pacakge to python2 package:

    https://packages.ubuntu.com/search?keywords=python2&searchon=names&suite=all&section=all

> Will queue.  Thanks.

Thanks.

-- Jiang Xin