Re: [PATCH 1/3] Use startup_info->prefix rather than prefix.

From: Junio C Hamano <gitster@pobox.com>
Date: Mar 3, 2012, 21:44 UTC
Message-ID: <7vbood742a.fsf@alter.siamese.dyndns.org>
In-Reply-To: <CACsJy8DtZLCLfeHNP_eq9kVZxjV3xh3gs6pgQCi=FDZ_Je7_Gw@mail.gmail.com>

Nguyen Thai Ngoc Duy <pclouds@gmail.com> writes:

> This patch makes this function only usable when startup_info pointer
> is initialized. As "git" binary is the only caller, the change is ok.
> If non-builtin commands want to use this function, they need to
> initialize startup_info first.

Hrm, that explanation is understandable, but it strongly makes me suspect that this change is making the code _more_ error prone in the longer term.

When somebody wants to add a new caller to a non-builtin, they need to think about what prefix to pass, and would realize that they need to call setup_git_directory() to get it. With the updated code, they can totally forget and call it without any initialized startup_info.

Adding a totally new command is rare, new non-builtin is rarer, and adding trace to it is even more so, so it may not be worth worrying about, but I wonder if there is a cheap way to check such a programming mistake.