From d9a93575722d9ea918f090892b06618ddf0d1d65 Mon Sep 17 00:00:00 2001
From: Chris Webb <chris@arachsys.com>
Date: Mon, 9 Jul 2012 19:53:26 +0100
Subject: [PATCH] Allow edit of empty message with commit --amend
"git commit --amend" used on a commit with an empty message fails
unless -m is given, whether or not --allow-empty-message is
specified.
Allow it to proceed to the editor with an empty commit message.
Unless --allow-empty-message is in force, it will still abort later
if an empty message is saved from the editor (this check was
already necessary to prevent a non-empty commit message being edited
to an empty one).
Add a test for --amend --edit of an empty commit message which fails
without this fix, as it's a rare case that won't get frequently
tested otherwise.
Signed-off-by: Chris Webb <chris@arachsys.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
builtin/commit.c | 2 +-
t/t7501-commit.sh | 15 +++++++++++++++
2 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/builtin/commit.c b/builtin/commit.c
index eae5a29aeb4..4b4e7e797f4 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -690,7 +690,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
hook_arg1 = "message";
} else if (use_message) {
buffer = strstr(use_message_buffer, "\n\n");
- if (!buffer || buffer[2] == '\0')
+ if (!use_editor && (!buffer || buffer[2] == '\0'))
die(_("commit has empty message"));
strbuf_add(&sb, buffer + 2, strlen(buffer + 2));
hook_arg1 = "commit";
diff --git a/t/t7501-commit.sh b/t/t7501-commit.sh
index 8bb38337a97..19593f8fbab 100755
--- a/t/t7501-commit.sh
+++ b/t/t7501-commit.sh
@@ -124,6 +124,21 @@ test_expect_success '--amend --edit' '
test_cmp expect msg
'
+test_expect_success '--amend --edit of empty message' '
+ cat >replace <<-\EOF &&
+ #!/bin/sh
+ echo "amended" >"$1"
+ EOF
+ chmod 755 replace &&
+ git commit --allow-empty --allow-empty-message -m "" &&
+ echo more bongo >file &&
+ git add file &&
+ EDITOR=./replace git commit --edit --amend &&
+ git diff-tree -s --format=%s HEAD >msg &&
+ ./replace expect &&
+ test_cmp expect msg
+'
+
test_expect_success '-m --edit' '
echo amended >expect &&
git commit --allow-empty -m buffer &&