Re: [PATCH] difftool: print list of valid tools with '--tool-help'

From: Junio C Hamano <gitster@pobox.com>
Date: Mar 23, 2012, 19:48 UTC
Message-ID: <7vzkb7rtd0.fsf@alter.siamese.dyndns.org>
In-Reply-To: <CAFouethYEmY7g3Uw0HfFMOKFNcBv=TyAsSyEkBU-cQrhaf6v7g@mail.gmail.com>

Tim Henigan <tim.henigan@gmail.com> writes:

Show 8 quoted lines

> Rather than create a new entry point, I used the existing
> 'get_merge_tool_path' that resides in 'git-mergetool--lib' to
> determine if a given tool is actually installed on the system.
>
> The '$DISPLAY' variable is lost in this implementation, but honestly I
> don't understand how it was intended to be used.
>
> Does this look useful?

Sounds like a better way to do it.

The point of checking DISPLAY in "cando" is to allow for a tool that changes its behaviour when launched in terminal-only vs windowed environment. For example, if somebody tries to spawn a tool that *only* works in windowed environment (e.g. "kompare") in a terminal-only session, it would fail, and the "cando" mechanism was designed to allow a tool detect such a situation and excuse itself from the available tools list.

I think get_merge_tool_path could do the same thing (i.e. report "no executable available to run this tool" when appropriate), so I do not think you lost anything.