Re: [PATCH] Teach git-commit about commit message templates.

From: Steven Grimm <koreth@midwinter.com>
Date: Jul 23, 2007, 10:56 UTC
Message-ID: <46A48949.1020501@midwinter.com>
In-Reply-To: <Pine.LNX.4.64.0707231136530.14781@racer.site>

Johannes Schindelin wrote:

Show 11 quoted lines

> Ah, I missed that.  But IIRC your patch does not wrap that logic behind 
> test ! -z "$templatefile", right?  So this is my modified suggestion:
>
> test ! -z "$templatefile" && {
> 	grep -vie '^Signed-off-by:' < "$GIT_DIR"/COMMIT_MSG" > "$GIT_DIR"/tmp1
> 	grep -ve '^#' < "$templatefile" > "$GIT_DIR"/tmp1
> 	trap 'rm "$GIT_DIR"/tmp[12]' 0
> 	cmp "$GIT_DIR"/tmp[12] &&
> 	die "Unchanged message; will not commit"
> }
>

So you are suggesting I do this in addition to the existing git-commit stripping of Signed-off-by: lines? I can certainly do that, but I didn't want to make two passes over the commit message doing exactly the same stripping.

Hmm, maybe I should outline my understanding of the current (unpatched) behavior and what I want it to do. Currently:

* Strip off all comment lines (happens when COMMIT_MSG is created)
* Strip off all Signed-off-by: lines
* Trim whitespace
* If the result has no content (`wc -l` == 0), abort.

With the patch, my intent was:

* Strip off all comment lines
* Strip off all Signed-off-by: lines
* Trim whitespace
* If the result has no content (! -s file), abort.
* If a template file was specified:
   * Strip off all comment and Signed-off-by: lines from the template
   * Trim whitespace from the template
   * If the resulting trimmed template is the same as the trimmed commit 
message, abort.

So I guess before getting to the specifics of the code, I'll ask: does the above make sense as a design? I wanted to preserve the existing behavior in the absence of a template.

Since the existing code is already stripping Signed-off-by: lines to test for a zero-length commit message, I figured I should reuse that work. However, it's no big deal to do it twice if people feel that results in more readable code -- certainly no human will ever notice the time it takes to re-grep the commit message.

-Steve