Re: [PATCH] interpret-trailers: obey scissors lines
- Date: Mon, 15 May 2017 12:55:42 +0900
- From: Junio C Hamano <gitster@xxxxxxxxx>
- Subject: Re: [PATCH] interpret-trailers: obey scissors lines
Brian Malehorn <bmalehorn@xxxxxxxxx> writes:
> If a commit message is being edited as "verbose", it will contain a
> scissors string ("-- >8 --") and a diff:
> my subject
> # ------------------------ >8 ------------------------
> # Do not touch the line above.
> # Everything below will be removed.
> diff --git a/foo.txt b/foo.txt
> index 5716ca5..7601807 100644
> --- a/foo.txt
> +++ b/foo.txt
> @@ -1 +1 @@
> interpret-trailers doesn't interpret the scissors and therefore places
> trailer information after the diff. A simple reproduction is:
> git config commit.verbose true
> GIT_EDITOR='git interpret-trailers --in-place --trailer Acked-by:me' \
> git commit --amend
> This commit resolves the issue by teaching "git interpret-trailers" to
> obey scissors the same way "git commit" does.
I'd prefer to see s/obey scissors lines/honor the cut line/, and the
last paragraph rephrased somewhat, perhaps like:
Subject: interpret-trailers: honor the cut line
If a commit message is edited with the "verbose" option, the
buffer will have a cut line and diff after the log message,
# ------------------------ >8 ------------------------
# Do not touch the line above.
# Everything below will be removed.
diff --git a/foo.txt b/foo.txt
index 5716ca5..7601807 100644
@@ -1 +1 @@
"git interpret-trailers" is unaware of the cut line, and
assumes the trailer block would be at the end of the whole
thing. This can easily be seen with:
$ GIT_EDITOR='git interpret-trailers --in-place --trailer Acked-by:me' \
git commit --amend -v
Teach "git interpret-trailers" to notice the cut-line and
ignore the remainder of the input when looking for a place
to add new trailer block. This makes it consistent with how
"git commit -v -s" inserts a new Signed-off-by: line.
This can be done by the same logic as the existing helper
function, wt_status_truncate_message_at_cut_line(), uses,
but it wants the caller to pass a strbuf to it. Because the
helper function ignore_non_trailer() used by the command
takes a <pointer, length> pair, not a strbuf, steal the
logic from wt_status_truncate_message_at_cut_line() to
create a new wt_status_strip_scissors() helper function that
takes <poiter, length> pair, and make ignore_non_trailer()
call it to help "interpret-trailers". Since there is only
one caller of wt_status_truncate_message_at_cut_line() in
cmd_commit(), rewrite it to call wt_status_strip_scissors()
helper instead and remove the old helper that no longer has
The last paragraph would have saved me from getting puzzled.
The mention of "'commit -v -s' works that way, too" was my attempt
to justify why it is OK to make this change unconditionally to
intepret-trailers, but I am still not 100% convinced with that
reasoning (or your original log message) that it is a safe thing to
do. It is not like its sole purpose is to serve as GIT_EDITOR for
the "git commit" command.
The patch text itself looks sensible.
We still need to see your patch with your sign-off, though.