Re: [PATCH 1/4] bash: improve aliased command recognition

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 23, 2010, 22:11 UTC
Message-ID: <7v3a0rd2lz.fsf@alter.siamese.dyndns.org>
In-Reply-To: <90724961a941edd1317514dea0a1c64112dab61d.1266958460.git.szeder@ira.uka.de>

SZEDER Gábor <szeder@ira.uka.de> writes:

Show 11 quoted lines

> [alias]
>     lgm = "!sh -c 'GIT_NOTES_REF=refs/notes/amlog git log \"$@\" || :' -"
>
> The full parsing of a shell command alias like that in the completion
> code is clearly unfeasible.  However, we can easily improve on aliased
> command recognition by eleminating stuff that is definitely not a git
> command: shell commands (anything starting with '!'), command line
> options (anything starting with '-'), environment variables (anything
> with a '=' in it), and git itself.  This way the above alias would be
> handled correctly, and the completion script would correctly recognize
> "log" as the aliased git command.

I personally do not think such a heuristic is worth the trouble (both for writing and maintaining the completion code nor runtime overhead to iterate over words on the expansion).

I vaguely recall somebody floated an idea to tell completion code that "you may not know what lgm is, but it takes the same set of options as log" (either via config or a shell function---I don't recall the details). I think that would be a lot more robust, efficient and easy to explain solution to the same problem.