Re: Allow git alias to override existing Git commands

From: Stefan Beller <sbeller@google.com>
Date: Nov 10, 2015, 18:12 UTC
Message-ID: <CAGZ79kZxQWVMe3N1ti8npyp9_4DUPAVy9Uk5a75Jwh3Eud2eZQ@mail.gmail.com>
In-Reply-To: <56421BD9.5060501@game-point.net>

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.

Show 6 quoted lines

>
> For example, I wanted to setup "git clone" to automatically act as "git
> clone --recursive".  Sure I could do it in the shell, but it's more of a
> pain - any tutorial I set up about doing it would have to worry about what
> shell the user was using - and if you're going to make that argument, why
> have "git alias" at all?  It can all be done from the shell.

I think the git way for your example would be to configure git to include that option by default, something like

    git config --global submodules.recursiveClone yes

though I was skimming through the man page of git config and did not find that option there. I guess it's missing.

Show 13 quoted lines

>
> Obviously I could also use a different alias that wasn't an existing Git
> command for this behaviour, but that would rather defeat the point: I want
> "git clone" to have different functionality.  If I remembered to use a
> different Git command, I might as well remember to type "git clone
> --recursive".  Also, if a future Git command were introduced with the same
> name as my alias, my alias's functionality would suddenly be ignored, giving
> unexpected behaviour.
>
> The reasoning behind this that it's "to avoid confusion and troubles with
> script usage" seems to be at odds with the general Git mentality that the
> user is given lots of power, and if they screw it up it's basically just
> user error.

For scripting the plumbing commands are recommended. The plumbing commands usually cannot be configured to do crazy stuff.

> For example, Git doesn't *have* to allow you to rebase.  It's a
> potentially dangerous operation, so why is it allowed?  It might "cause
> confusion and troubles".

Git doesn't try to hide its complexity from the users. And if a user would need to hack their way around to get rebasing working again, might also "cause confusion and troubles".

Show 16 quoted lines

>
> On the other hand, by disallowing the overriding of existing Git commands
> through aliases you are preventing a lot of useful functionality that those
> aliases might be used for.
>
> So I think you should either allow Git aliases to override existing Git
> commands by default, or at least provide a config option that allows the
> user to say that this should happen.
>
> --
> Best regards,
> Jeremy Morton (Jez)
> --
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