Re: [RFC/PATCH] commit notes workflow

@@ -233,8 +233,7 @@ configuration variable documented in linkgit:git-config[1].
 --verbose::
 	Show unified diff between the HEAD commit and what
 	would be committed at the bottom of the commit message
-	template.  Note that this diff output doesn't have its
-	lines prefixed with '#'.
+	template.
 
 -q::
 --quiet::

@@ -1381,13 +1381,6 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 		die("could not read commit message: %s", strerror(saved_errno));
 	}
 
-	/* Truncate the message just before the diff, if any. */
-	if (verbose) {
-		p = strstr(sb.buf, "\ndiff --git ");
-		if (p != NULL)
-			strbuf_setlen(&sb, p - sb.buf + 1);
-	}
-
 	if (cleanup_mode != CLEANUP_NONE)
 		stripspace(&sb, cleanup_mode == CLEANUP_ALL);
 	if (message_is_empty(&sb) && !allow_empty_message) {

@@ -79,7 +79,7 @@ test_expect_success 'format-patch produces binary' '
 test_expect_success 'status -v produces text' '
 	git reset --soft HEAD^ &&
 	git status -v >diff &&
-	find_diff <diff >actual &&
+	sed -e "s/^# //" <diff | find_diff >actual &&
 	test_cmp expect.text actual &&
 	git reset --soft HEAD@{1}
 '

@@ -151,8 +151,8 @@ test_expect_success 'verbose' '
 
 	echo minus >negative &&
 	git add negative &&
-	git status -v | sed -ne "/^diff --git /p" >actual &&
-	echo "diff --git a/negative b/negative" >expect &&
+	git status -v | sed -ne "/^# diff --git /p" >actual &&
+	echo "# diff --git a/negative b/negative" >expect &&
 	test_cmp expect actual
 
 '

@@ -5,7 +5,7 @@ test_description='verbose commit template'
 
 cat >check-for-diff <<EOF
 #!$SHELL_PATH
-exec grep '^diff --git' "\$1"
+exec grep '^# diff --git' "\$1"
 EOF
 chmod +x check-for-diff
 test_set_editor "$PWD/check-for-diff"

@@ -65,7 +65,7 @@ test_expect_success 'diff in message is retained without -v' '
 	check_message diff
 '
 
-test_expect_failure 'diff in message is retained with -v' '
+test_expect_success 'diff in message is retained with -v' '
 	git commit --amend -F diff -v &&
 	check_message diff
 '

@@ -32,6 +32,12 @@ static const char *color(int slot, struct wt_status *s)
 	return c;
 }
 
+static struct strbuf *diff_output_prefix_callback(struct diff_options *opt, void *data)
+{
+	assert(data);
+	return (struct strbuf *)data;
+}
+
 void wt_status_prepare(struct wt_status *s)
 {
 	unsigned char sha1[20];

@@ -588,6 +594,7 @@ static void wt_status_print_verbose(struct wt_status *s)
 {
 	struct rev_info rev;
 	struct setup_revision_opt opt;
+	struct strbuf diff_output_prefix = STRBUF_INIT;
 
 	init_revisions(&rev, NULL);
 	DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);

@@ -596,10 +603,14 @@ static void wt_status_print_verbose(struct wt_status *s)
 	opt.def = s->is_initial ? EMPTY_TREE_SHA1_HEX : s->reference;
 	setup_revisions(0, NULL, &rev, &opt);
 
+	strbuf_addstr(&diff_output_prefix, "# ");
+
 	rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
 	rev.diffopt.detect_rename = 1;
 	rev.diffopt.file = s->fp;
 	rev.diffopt.close_file = 0;
+	rev.diffopt.output_prefix = diff_output_prefix_callback;
+	rev.diffopt.output_prefix_data = &diff_output_prefix;
 	/*
 	 * If we're not going to stdout, then we definitely don't
 	 * want color, since we are going to the commit message

@@ -609,6 +620,7 @@ static void wt_status_print_verbose(struct wt_status *s)
 	if (s->fp != stdout)
 		DIFF_OPT_CLR(&rev.diffopt, COLOR_DIFF);
 	run_diff_index(&rev, 1);
+	strbuf_release(&diff_output_prefix);
 }
 
 static void wt_status_print_tracking(struct wt_status *s)