Re: Allow git alias to override existing Git commands

From: Sitaram Chamarty <sitaramc@gmail.com>
Date: Nov 11, 2015, 04:48 UTC
Message-ID: <5642C8BA.8030003@gmail.com>
In-Reply-To: <56424DDE.2030808@game-point.net>

On 11/11/15 01:34, Jeremy Morton wrote:

Show 17 quoted lines

> On 10/11/2015 18:12, Stefan Beller wrote:
>> On Tue, Nov 10, 2015 at 8:31 AM, Jeremy Morton<admin@game-point.net>  wrote:
>>> It's recently come to my attention that the "git alias" config functionality
>>> ignores all aliases that would override existing Git commands.  This seems
>>> like a bad idea to me.
>>
>> This ensures that the plumbing commands always work as expected.
>> As scripts *should* only use plumbing commands, the scripts should
>> work with high probability despite all the crazy user configuration/aliases.
>>
> 
> I just disagree with this.  If a user chooses to override their Git
> commands, it's their problem.  Why should Git care about this?  It
> should provide the user with the option to do this, and if the user
> ruins scripts because of their aliases, it is not Git's problem.  What
> you are doing is taking away power from users to use git aliases to
> their full potential.

A lot of things in Unix do follow that "give you rope to hang yourself" philosophy. I used to (and to *some* extent still do) think like that, but some years of supporting normal users trying to do stuff has taught me it's not always that simple.

I can easily see someone blogging some cool way to do something, and a less savvy user uses that in his gitconfig, and gets burned later (possibly much later, enough that he does not easily make the connection!)

So for the record, I am definitely against this kind of change.

But if I were in your place, and really *needed* this, here's what I would do:

    #!/bin/bash

    # this file is named 'git' and placed in a directory that is earlier in $PATH
    # than the real 'git' binary (typically $HOME/bin).  This allows you to
    # override git sub-commands by adding stuff like this to your ~/.gitconfig
    # (notice the "o-" prefix):
    #
    #   [alias]
    #       o-clone = clone --recursive

    GIT=/bin/git    # the real 'git' binary

    cmd="$1"
    shift

    if $GIT config --get alias.o-$cmd >/dev/null
    then
        $GIT o-$cmd "$@"
    else
        $GIT $cmd "$@"
    fi